mirror of https://gitee.com/openkylin/linux.git
1508 lines
38 KiB
C
1508 lines
38 KiB
C
/*
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* CARMA DATA-FPGA Access Driver
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*
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* Copyright (c) 2009-2011 Ira W. Snyder <iws@ovro.caltech.edu>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License as published by the
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* Free Software Foundation; either version 2 of the License, or (at your
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* option) any later version.
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*/
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/*
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* FPGA Memory Dump Format
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*
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* FPGA #0 control registers (32 x 32-bit words)
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* FPGA #1 control registers (32 x 32-bit words)
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* FPGA #2 control registers (32 x 32-bit words)
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* FPGA #3 control registers (32 x 32-bit words)
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* SYSFPGA control registers (32 x 32-bit words)
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* FPGA #0 correlation array (NUM_CORL0 correlation blocks)
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* FPGA #1 correlation array (NUM_CORL1 correlation blocks)
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* FPGA #2 correlation array (NUM_CORL2 correlation blocks)
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* FPGA #3 correlation array (NUM_CORL3 correlation blocks)
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*
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* Each correlation array consists of:
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*
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* Correlation Data (2 x NUM_LAGSn x 32-bit words)
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* Pipeline Metadata (2 x NUM_METAn x 32-bit words)
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* Quantization Counters (2 x NUM_QCNTn x 32-bit words)
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*
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* The NUM_CORLn, NUM_LAGSn, NUM_METAn, and NUM_QCNTn values come from
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* the FPGA configuration registers. They do not change once the FPGA's
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* have been programmed, they only change on re-programming.
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*/
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/*
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* Basic Description:
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*
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* This driver is used to capture correlation spectra off of the four data
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* processing FPGAs. The FPGAs are often reprogrammed at runtime, therefore
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* this driver supports dynamic enable/disable of capture while the device
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* remains open.
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*
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* The nominal capture rate is 64Hz (every 15.625ms). To facilitate this fast
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* capture rate, all buffers are pre-allocated to avoid any potentially long
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* running memory allocations while capturing.
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*
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* There are two lists and one pointer which are used to keep track of the
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* different states of data buffers.
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*
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* 1) free list
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* This list holds all empty data buffers which are ready to receive data.
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*
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* 2) inflight pointer
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* This pointer holds the currently inflight data buffer. This buffer is having
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* data copied into it by the DMA engine.
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*
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* 3) used list
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* This list holds data buffers which have been filled, and are waiting to be
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* read by userspace.
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*
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* All buffers start life on the free list, then move successively to the
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* inflight pointer, and then to the used list. After they have been read by
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* userspace, they are moved back to the free list. The cycle repeats as long
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* as necessary.
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*
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* It should be noted that all buffers are mapped and ready for DMA when they
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* are on any of the three lists. They are only unmapped when they are in the
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* process of being read by userspace.
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*/
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/*
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* Notes on the IRQ masking scheme:
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*
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* The IRQ masking scheme here is different than most other hardware. The only
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* way for the DATA-FPGAs to detect if the kernel has taken too long to copy
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* the data is if the status registers are not cleared before the next
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* correlation data dump is ready.
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*
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* The interrupt line is connected to the status registers, such that when they
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* are cleared, the interrupt is de-asserted. Therein lies our problem. We need
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* to schedule a long-running DMA operation and return from the interrupt
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* handler quickly, but we cannot clear the status registers.
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*
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* To handle this, the system controller FPGA has the capability to connect the
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* interrupt line to a user-controlled GPIO pin. This pin is driven high
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* (unasserted) and left that way. To mask the interrupt, we change the
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* interrupt source to the GPIO pin. Tada, we hid the interrupt. :)
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*/
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#include <linux/of_platform.h>
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#include <linux/dma-mapping.h>
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#include <linux/miscdevice.h>
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#include <linux/interrupt.h>
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#include <linux/dmaengine.h>
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#include <linux/seq_file.h>
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#include <linux/highmem.h>
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#include <linux/debugfs.h>
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#include <linux/vmalloc.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/poll.h>
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#include <linux/slab.h>
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#include <linux/kref.h>
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#include <linux/io.h>
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/* system controller registers */
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#define SYS_IRQ_SOURCE_CTL 0x24
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#define SYS_IRQ_OUTPUT_EN 0x28
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#define SYS_IRQ_OUTPUT_DATA 0x2C
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#define SYS_IRQ_INPUT_DATA 0x30
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#define SYS_FPGA_CONFIG_STATUS 0x44
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/* GPIO IRQ line assignment */
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#define IRQ_CORL_DONE 0x10
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/* FPGA registers */
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#define MMAP_REG_VERSION 0x00
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#define MMAP_REG_CORL_CONF1 0x08
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#define MMAP_REG_CORL_CONF2 0x0C
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#define MMAP_REG_STATUS 0x48
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#define SYS_FPGA_BLOCK 0xF0000000
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#define DATA_FPGA_START 0x400000
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#define DATA_FPGA_SIZE 0x80000
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static const char drv_name[] = "carma-fpga";
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#define NUM_FPGA 4
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#define MIN_DATA_BUFS 8
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#define MAX_DATA_BUFS 64
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struct fpga_info {
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unsigned int num_lag_ram;
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unsigned int blk_size;
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};
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struct data_buf {
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struct list_head entry;
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void *vaddr;
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struct scatterlist *sglist;
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int sglen;
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int nr_pages;
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size_t size;
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};
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struct fpga_device {
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/* character device */
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struct miscdevice miscdev;
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struct device *dev;
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struct mutex mutex;
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/* reference count */
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struct kref ref;
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/* FPGA registers and information */
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struct fpga_info info[NUM_FPGA];
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void __iomem *regs;
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int irq;
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/* FPGA Physical Address/Size Information */
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resource_size_t phys_addr;
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size_t phys_size;
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/* DMA structures */
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struct sg_table corl_table;
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unsigned int corl_nents;
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struct dma_chan *chan;
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/* Protection for all members below */
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spinlock_t lock;
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/* Device enable/disable flag */
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bool enabled;
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/* Correlation data buffers */
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wait_queue_head_t wait;
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struct list_head free;
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struct list_head used;
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struct data_buf *inflight;
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/* Information about data buffers */
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unsigned int num_dropped;
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unsigned int num_buffers;
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size_t bufsize;
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struct dentry *dbg_entry;
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};
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struct fpga_reader {
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struct fpga_device *priv;
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struct data_buf *buf;
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off_t buf_start;
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};
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static void fpga_device_release(struct kref *ref)
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{
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struct fpga_device *priv = container_of(ref, struct fpga_device, ref);
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/* the last reader has exited, cleanup the last bits */
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mutex_destroy(&priv->mutex);
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kfree(priv);
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}
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/*
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* Data Buffer Allocation Helpers
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*/
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static int carma_dma_init(struct data_buf *buf, int nr_pages)
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{
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struct page *pg;
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int i;
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buf->vaddr = vmalloc_32(nr_pages << PAGE_SHIFT);
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if (NULL == buf->vaddr) {
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pr_debug("vmalloc_32(%d pages) failed\n", nr_pages);
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return -ENOMEM;
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}
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pr_debug("vmalloc is at addr 0x%08lx, size=%d\n",
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(unsigned long)buf->vaddr,
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nr_pages << PAGE_SHIFT);
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memset(buf->vaddr, 0, nr_pages << PAGE_SHIFT);
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buf->nr_pages = nr_pages;
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buf->sglist = vzalloc(buf->nr_pages * sizeof(*buf->sglist));
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if (NULL == buf->sglist)
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goto vzalloc_err;
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sg_init_table(buf->sglist, buf->nr_pages);
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for (i = 0; i < buf->nr_pages; i++) {
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pg = vmalloc_to_page(buf->vaddr + i * PAGE_SIZE);
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if (NULL == pg)
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goto vmalloc_to_page_err;
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sg_set_page(&buf->sglist[i], pg, PAGE_SIZE, 0);
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}
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return 0;
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vmalloc_to_page_err:
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vfree(buf->sglist);
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buf->sglist = NULL;
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vzalloc_err:
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vfree(buf->vaddr);
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buf->vaddr = NULL;
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return -ENOMEM;
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}
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static int carma_dma_map(struct device *dev, struct data_buf *buf)
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{
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buf->sglen = dma_map_sg(dev, buf->sglist,
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buf->nr_pages, DMA_FROM_DEVICE);
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if (0 == buf->sglen) {
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pr_warn("%s: dma_map_sg failed\n", __func__);
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return -ENOMEM;
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}
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return 0;
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}
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static int carma_dma_unmap(struct device *dev, struct data_buf *buf)
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{
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if (!buf->sglen)
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return 0;
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dma_unmap_sg(dev, buf->sglist, buf->sglen, DMA_FROM_DEVICE);
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buf->sglen = 0;
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return 0;
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}
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/**
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* data_free_buffer() - free a single data buffer and all allocated memory
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* @buf: the buffer to free
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*
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* This will free all of the pages allocated to the given data buffer, and
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* then free the structure itself
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*/
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static void data_free_buffer(struct data_buf *buf)
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{
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/* It is ok to free a NULL buffer */
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if (!buf)
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return;
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/* free all memory */
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vfree(buf->sglist);
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vfree(buf->vaddr);
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kfree(buf);
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}
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/**
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* data_alloc_buffer() - allocate and fill a data buffer with pages
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* @bytes: the number of bytes required
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*
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* This allocates all space needed for a data buffer. It must be mapped before
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* use in a DMA transaction using carma_dma_map().
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*
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* Returns NULL on failure
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*/
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static struct data_buf *data_alloc_buffer(const size_t bytes)
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{
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unsigned int nr_pages;
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struct data_buf *buf;
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int ret;
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/* calculate the number of pages necessary */
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nr_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
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/* allocate the buffer structure */
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buf = kzalloc(sizeof(*buf), GFP_KERNEL);
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if (!buf)
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goto out_return;
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/* initialize internal fields */
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INIT_LIST_HEAD(&buf->entry);
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buf->size = bytes;
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/* allocate the buffer */
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ret = carma_dma_init(buf, nr_pages);
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if (ret)
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goto out_free_buf;
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return buf;
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out_free_buf:
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kfree(buf);
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out_return:
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return NULL;
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}
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/**
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* data_free_buffers() - free all allocated buffers
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* @priv: the driver's private data structure
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*
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* Free all buffers allocated by the driver (except those currently in the
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* process of being read by userspace).
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*
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* LOCKING: must hold dev->mutex
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* CONTEXT: user
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*/
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static void data_free_buffers(struct fpga_device *priv)
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{
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struct data_buf *buf, *tmp;
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/* the device should be stopped, no DMA in progress */
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BUG_ON(priv->inflight != NULL);
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list_for_each_entry_safe(buf, tmp, &priv->free, entry) {
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list_del_init(&buf->entry);
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carma_dma_unmap(priv->dev, buf);
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data_free_buffer(buf);
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}
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list_for_each_entry_safe(buf, tmp, &priv->used, entry) {
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list_del_init(&buf->entry);
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carma_dma_unmap(priv->dev, buf);
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data_free_buffer(buf);
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}
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priv->num_buffers = 0;
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priv->bufsize = 0;
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}
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/**
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* data_alloc_buffers() - allocate 1 seconds worth of data buffers
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* @priv: the driver's private data structure
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*
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* Allocate enough buffers for a whole second worth of data
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*
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* This routine will attempt to degrade nicely by succeeding even if a full
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* second worth of data buffers could not be allocated, as long as a minimum
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* number were allocated. In this case, it will print a message to the kernel
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* log.
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*
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* The device must not be modifying any lists when this is called.
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*
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* CONTEXT: user
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* LOCKING: must hold dev->mutex
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*
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* Returns 0 on success, -ERRNO otherwise
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*/
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static int data_alloc_buffers(struct fpga_device *priv)
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{
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struct data_buf *buf;
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int i, ret;
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for (i = 0; i < MAX_DATA_BUFS; i++) {
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/* allocate a buffer */
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buf = data_alloc_buffer(priv->bufsize);
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if (!buf)
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break;
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/* map it for DMA */
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ret = carma_dma_map(priv->dev, buf);
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if (ret) {
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data_free_buffer(buf);
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break;
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}
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/* add it to the list of free buffers */
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list_add_tail(&buf->entry, &priv->free);
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priv->num_buffers++;
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}
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/* Make sure we allocated the minimum required number of buffers */
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if (priv->num_buffers < MIN_DATA_BUFS) {
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dev_err(priv->dev, "Unable to allocate enough data buffers\n");
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data_free_buffers(priv);
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return -ENOMEM;
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}
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/* Warn if we are running in a degraded state, but do not fail */
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if (priv->num_buffers < MAX_DATA_BUFS) {
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dev_warn(priv->dev,
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"Unable to allocate %d buffers, using %d buffers instead\n",
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MAX_DATA_BUFS, i);
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}
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return 0;
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}
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/*
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* DMA Operations Helpers
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*/
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/**
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* fpga_start_addr() - get the physical address a DATA-FPGA
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* @priv: the driver's private data structure
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* @fpga: the DATA-FPGA number (zero based)
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*/
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static dma_addr_t fpga_start_addr(struct fpga_device *priv, unsigned int fpga)
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{
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return priv->phys_addr + 0x400000 + (0x80000 * fpga);
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}
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/**
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* fpga_block_addr() - get the physical address of a correlation data block
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* @priv: the driver's private data structure
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* @fpga: the DATA-FPGA number (zero based)
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* @blknum: the correlation block number (zero based)
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*/
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static dma_addr_t fpga_block_addr(struct fpga_device *priv, unsigned int fpga,
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unsigned int blknum)
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{
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return fpga_start_addr(priv, fpga) + (0x10000 * (1 + blknum));
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}
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#define REG_BLOCK_SIZE (32 * 4)
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/**
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* data_setup_corl_table() - create the scatterlist for correlation dumps
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* @priv: the driver's private data structure
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*
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* Create the scatterlist for transferring a correlation dump from the
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* DATA FPGAs. This structure will be reused for each buffer than needs
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* to be filled with correlation data.
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*
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* Returns 0 on success, -ERRNO otherwise
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*/
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static int data_setup_corl_table(struct fpga_device *priv)
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{
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struct sg_table *table = &priv->corl_table;
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struct scatterlist *sg;
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struct fpga_info *info;
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int i, j, ret;
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/* Calculate the number of entries needed */
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priv->corl_nents = (1 + NUM_FPGA) * REG_BLOCK_SIZE;
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for (i = 0; i < NUM_FPGA; i++)
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priv->corl_nents += priv->info[i].num_lag_ram;
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/* Allocate the scatterlist table */
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ret = sg_alloc_table(table, priv->corl_nents, GFP_KERNEL);
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if (ret) {
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dev_err(priv->dev, "unable to allocate DMA table\n");
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return ret;
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}
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/* Add the DATA FPGA registers to the scatterlist */
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sg = table->sgl;
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for (i = 0; i < NUM_FPGA; i++) {
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sg_dma_address(sg) = fpga_start_addr(priv, i);
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sg_dma_len(sg) = REG_BLOCK_SIZE;
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sg = sg_next(sg);
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}
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/* Add the SYS-FPGA registers to the scatterlist */
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sg_dma_address(sg) = SYS_FPGA_BLOCK;
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sg_dma_len(sg) = REG_BLOCK_SIZE;
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sg = sg_next(sg);
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/* Add the FPGA correlation data blocks to the scatterlist */
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for (i = 0; i < NUM_FPGA; i++) {
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info = &priv->info[i];
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for (j = 0; j < info->num_lag_ram; j++) {
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sg_dma_address(sg) = fpga_block_addr(priv, i, j);
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sg_dma_len(sg) = info->blk_size;
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sg = sg_next(sg);
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}
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}
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|
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/*
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* All physical addresses and lengths are present in the structure
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* now. It can be reused for every FPGA DATA interrupt
|
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*/
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return 0;
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}
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|
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/*
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* FPGA Register Access Helpers
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*/
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|
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static void fpga_write_reg(struct fpga_device *priv, unsigned int fpga,
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unsigned int reg, u32 val)
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{
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const int fpga_start = DATA_FPGA_START + (fpga * DATA_FPGA_SIZE);
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iowrite32be(val, priv->regs + fpga_start + reg);
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}
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|
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static u32 fpga_read_reg(struct fpga_device *priv, unsigned int fpga,
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unsigned int reg)
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{
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const int fpga_start = DATA_FPGA_START + (fpga * DATA_FPGA_SIZE);
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return ioread32be(priv->regs + fpga_start + reg);
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}
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|
|
/**
|
|
* data_calculate_bufsize() - calculate the data buffer size required
|
|
* @priv: the driver's private data structure
|
|
*
|
|
* Calculate the total buffer size needed to hold a single block
|
|
* of correlation data
|
|
*
|
|
* CONTEXT: user
|
|
*
|
|
* Returns 0 on success, -ERRNO otherwise
|
|
*/
|
|
static int data_calculate_bufsize(struct fpga_device *priv)
|
|
{
|
|
u32 num_corl, num_lags, num_meta, num_qcnt, num_pack;
|
|
u32 conf1, conf2, version;
|
|
u32 num_lag_ram, blk_size;
|
|
int i;
|
|
|
|
/* Each buffer starts with the 5 FPGA register areas */
|
|
priv->bufsize = (1 + NUM_FPGA) * REG_BLOCK_SIZE;
|
|
|
|
/* Read and store the configuration data for each FPGA */
|
|
for (i = 0; i < NUM_FPGA; i++) {
|
|
version = fpga_read_reg(priv, i, MMAP_REG_VERSION);
|
|
conf1 = fpga_read_reg(priv, i, MMAP_REG_CORL_CONF1);
|
|
conf2 = fpga_read_reg(priv, i, MMAP_REG_CORL_CONF2);
|
|
|
|
/* minor version 2 and later */
|
|
if ((version & 0x000000FF) >= 2) {
|
|
num_corl = (conf1 & 0x000000F0) >> 4;
|
|
num_pack = (conf1 & 0x00000F00) >> 8;
|
|
num_lags = (conf1 & 0x00FFF000) >> 12;
|
|
num_meta = (conf1 & 0x7F000000) >> 24;
|
|
num_qcnt = (conf2 & 0x00000FFF) >> 0;
|
|
} else {
|
|
num_corl = (conf1 & 0x000000F0) >> 4;
|
|
num_pack = 1; /* implied */
|
|
num_lags = (conf1 & 0x000FFF00) >> 8;
|
|
num_meta = (conf1 & 0x7FF00000) >> 20;
|
|
num_qcnt = (conf2 & 0x00000FFF) >> 0;
|
|
}
|
|
|
|
num_lag_ram = (num_corl + num_pack - 1) / num_pack;
|
|
blk_size = ((num_pack * num_lags) + num_meta + num_qcnt) * 8;
|
|
|
|
priv->info[i].num_lag_ram = num_lag_ram;
|
|
priv->info[i].blk_size = blk_size;
|
|
priv->bufsize += num_lag_ram * blk_size;
|
|
|
|
dev_dbg(priv->dev, "FPGA %d NUM_CORL: %d\n", i, num_corl);
|
|
dev_dbg(priv->dev, "FPGA %d NUM_PACK: %d\n", i, num_pack);
|
|
dev_dbg(priv->dev, "FPGA %d NUM_LAGS: %d\n", i, num_lags);
|
|
dev_dbg(priv->dev, "FPGA %d NUM_META: %d\n", i, num_meta);
|
|
dev_dbg(priv->dev, "FPGA %d NUM_QCNT: %d\n", i, num_qcnt);
|
|
dev_dbg(priv->dev, "FPGA %d BLK_SIZE: %d\n", i, blk_size);
|
|
}
|
|
|
|
dev_dbg(priv->dev, "TOTAL BUFFER SIZE: %zu bytes\n", priv->bufsize);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Interrupt Handling
|
|
*/
|
|
|
|
/**
|
|
* data_disable_interrupts() - stop the device from generating interrupts
|
|
* @priv: the driver's private data structure
|
|
*
|
|
* Hide interrupts by switching to GPIO interrupt source
|
|
*
|
|
* LOCKING: must hold dev->lock
|
|
*/
|
|
static void data_disable_interrupts(struct fpga_device *priv)
|
|
{
|
|
/* hide the interrupt by switching the IRQ driver to GPIO */
|
|
iowrite32be(0x2F, priv->regs + SYS_IRQ_SOURCE_CTL);
|
|
}
|
|
|
|
/**
|
|
* data_enable_interrupts() - allow the device to generate interrupts
|
|
* @priv: the driver's private data structure
|
|
*
|
|
* Unhide interrupts by switching to the FPGA interrupt source. At the
|
|
* same time, clear the DATA-FPGA status registers.
|
|
*
|
|
* LOCKING: must hold dev->lock
|
|
*/
|
|
static void data_enable_interrupts(struct fpga_device *priv)
|
|
{
|
|
/* clear the actual FPGA corl_done interrupt */
|
|
fpga_write_reg(priv, 0, MMAP_REG_STATUS, 0x0);
|
|
fpga_write_reg(priv, 1, MMAP_REG_STATUS, 0x0);
|
|
fpga_write_reg(priv, 2, MMAP_REG_STATUS, 0x0);
|
|
fpga_write_reg(priv, 3, MMAP_REG_STATUS, 0x0);
|
|
|
|
/* flush the writes */
|
|
fpga_read_reg(priv, 0, MMAP_REG_STATUS);
|
|
fpga_read_reg(priv, 1, MMAP_REG_STATUS);
|
|
fpga_read_reg(priv, 2, MMAP_REG_STATUS);
|
|
fpga_read_reg(priv, 3, MMAP_REG_STATUS);
|
|
|
|
/* switch back to the external interrupt source */
|
|
iowrite32be(0x3F, priv->regs + SYS_IRQ_SOURCE_CTL);
|
|
}
|
|
|
|
/**
|
|
* data_dma_cb() - DMAEngine callback for DMA completion
|
|
* @data: the driver's private data structure
|
|
*
|
|
* Complete a DMA transfer from the DATA-FPGA's
|
|
*
|
|
* This is called via the DMA callback mechanism, and will handle moving the
|
|
* completed DMA transaction to the used list, and then wake any processes
|
|
* waiting for new data
|
|
*
|
|
* CONTEXT: any, softirq expected
|
|
*/
|
|
static void data_dma_cb(void *data)
|
|
{
|
|
struct fpga_device *priv = data;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&priv->lock, flags);
|
|
|
|
/* If there is no inflight buffer, we've got a bug */
|
|
BUG_ON(priv->inflight == NULL);
|
|
|
|
/* Move the inflight buffer onto the used list */
|
|
list_move_tail(&priv->inflight->entry, &priv->used);
|
|
priv->inflight = NULL;
|
|
|
|
/*
|
|
* If data dumping is still enabled, then clear the FPGA
|
|
* status registers and re-enable FPGA interrupts
|
|
*/
|
|
if (priv->enabled)
|
|
data_enable_interrupts(priv);
|
|
|
|
spin_unlock_irqrestore(&priv->lock, flags);
|
|
|
|
/*
|
|
* We've changed both the inflight and used lists, so we need
|
|
* to wake up any processes that are blocking for those events
|
|
*/
|
|
wake_up(&priv->wait);
|
|
}
|
|
|
|
/**
|
|
* data_submit_dma() - prepare and submit the required DMA to fill a buffer
|
|
* @priv: the driver's private data structure
|
|
* @buf: the data buffer
|
|
*
|
|
* Prepare and submit the necessary DMA transactions to fill a correlation
|
|
* data buffer.
|
|
*
|
|
* LOCKING: must hold dev->lock
|
|
* CONTEXT: hardirq only
|
|
*
|
|
* Returns 0 on success, -ERRNO otherwise
|
|
*/
|
|
static int data_submit_dma(struct fpga_device *priv, struct data_buf *buf)
|
|
{
|
|
struct scatterlist *dst_sg, *src_sg;
|
|
unsigned int dst_nents, src_nents;
|
|
struct dma_chan *chan = priv->chan;
|
|
struct dma_async_tx_descriptor *tx;
|
|
dma_cookie_t cookie;
|
|
dma_addr_t dst, src;
|
|
unsigned long dma_flags = 0;
|
|
|
|
dst_sg = buf->sglist;
|
|
dst_nents = buf->sglen;
|
|
|
|
src_sg = priv->corl_table.sgl;
|
|
src_nents = priv->corl_nents;
|
|
|
|
/*
|
|
* All buffers passed to this function should be ready and mapped
|
|
* for DMA already. Therefore, we don't need to do anything except
|
|
* submit it to the Freescale DMA Engine for processing
|
|
*/
|
|
|
|
/* setup the scatterlist to scatterlist transfer */
|
|
tx = chan->device->device_prep_dma_sg(chan,
|
|
dst_sg, dst_nents,
|
|
src_sg, src_nents,
|
|
0);
|
|
if (!tx) {
|
|
dev_err(priv->dev, "unable to prep scatterlist DMA\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* submit the transaction to the DMA controller */
|
|
cookie = tx->tx_submit(tx);
|
|
if (dma_submit_error(cookie)) {
|
|
dev_err(priv->dev, "unable to submit scatterlist DMA\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Prepare the re-read of the SYS-FPGA block */
|
|
dst = sg_dma_address(dst_sg) + (NUM_FPGA * REG_BLOCK_SIZE);
|
|
src = SYS_FPGA_BLOCK;
|
|
tx = chan->device->device_prep_dma_memcpy(chan, dst, src,
|
|
REG_BLOCK_SIZE,
|
|
dma_flags);
|
|
if (!tx) {
|
|
dev_err(priv->dev, "unable to prep SYS-FPGA DMA\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Setup the callback */
|
|
tx->callback = data_dma_cb;
|
|
tx->callback_param = priv;
|
|
|
|
/* submit the transaction to the DMA controller */
|
|
cookie = tx->tx_submit(tx);
|
|
if (dma_submit_error(cookie)) {
|
|
dev_err(priv->dev, "unable to submit SYS-FPGA DMA\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define CORL_DONE 0x1
|
|
#define CORL_ERR 0x2
|
|
|
|
static irqreturn_t data_irq(int irq, void *dev_id)
|
|
{
|
|
struct fpga_device *priv = dev_id;
|
|
bool submitted = false;
|
|
struct data_buf *buf;
|
|
u32 status;
|
|
int i;
|
|
|
|
/* detect spurious interrupts via FPGA status */
|
|
for (i = 0; i < 4; i++) {
|
|
status = fpga_read_reg(priv, i, MMAP_REG_STATUS);
|
|
if (!(status & (CORL_DONE | CORL_ERR))) {
|
|
dev_err(priv->dev, "spurious irq detected (FPGA)\n");
|
|
return IRQ_NONE;
|
|
}
|
|
}
|
|
|
|
/* detect spurious interrupts via raw IRQ pin readback */
|
|
status = ioread32be(priv->regs + SYS_IRQ_INPUT_DATA);
|
|
if (status & IRQ_CORL_DONE) {
|
|
dev_err(priv->dev, "spurious irq detected (IRQ)\n");
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
spin_lock(&priv->lock);
|
|
|
|
/*
|
|
* This is an error case that should never happen.
|
|
*
|
|
* If this driver has a bug and manages to re-enable interrupts while
|
|
* a DMA is in progress, then we will hit this statement and should
|
|
* start paying attention immediately.
|
|
*/
|
|
BUG_ON(priv->inflight != NULL);
|
|
|
|
/* hide the interrupt by switching the IRQ driver to GPIO */
|
|
data_disable_interrupts(priv);
|
|
|
|
/* If there are no free buffers, drop this data */
|
|
if (list_empty(&priv->free)) {
|
|
priv->num_dropped++;
|
|
goto out;
|
|
}
|
|
|
|
buf = list_first_entry(&priv->free, struct data_buf, entry);
|
|
list_del_init(&buf->entry);
|
|
BUG_ON(buf->size != priv->bufsize);
|
|
|
|
/* Submit a DMA transfer to get the correlation data */
|
|
if (data_submit_dma(priv, buf)) {
|
|
dev_err(priv->dev, "Unable to setup DMA transfer\n");
|
|
list_move_tail(&buf->entry, &priv->free);
|
|
goto out;
|
|
}
|
|
|
|
/* Save the buffer for the DMA callback */
|
|
priv->inflight = buf;
|
|
submitted = true;
|
|
|
|
/* Start the DMA Engine */
|
|
dma_async_issue_pending(priv->chan);
|
|
|
|
out:
|
|
/* If no DMA was submitted, re-enable interrupts */
|
|
if (!submitted)
|
|
data_enable_interrupts(priv);
|
|
|
|
spin_unlock(&priv->lock);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*
|
|
* Realtime Device Enable Helpers
|
|
*/
|
|
|
|
/**
|
|
* data_device_enable() - enable the device for buffered dumping
|
|
* @priv: the driver's private data structure
|
|
*
|
|
* Enable the device for buffered dumping. Allocates buffers and hooks up
|
|
* the interrupt handler. When this finishes, data will come pouring in.
|
|
*
|
|
* LOCKING: must hold dev->mutex
|
|
* CONTEXT: user context only
|
|
*
|
|
* Returns 0 on success, -ERRNO otherwise
|
|
*/
|
|
static int data_device_enable(struct fpga_device *priv)
|
|
{
|
|
bool enabled;
|
|
u32 val;
|
|
int ret;
|
|
|
|
/* multiple enables are safe: they do nothing */
|
|
spin_lock_irq(&priv->lock);
|
|
enabled = priv->enabled;
|
|
spin_unlock_irq(&priv->lock);
|
|
if (enabled)
|
|
return 0;
|
|
|
|
/* check that the FPGAs are programmed */
|
|
val = ioread32be(priv->regs + SYS_FPGA_CONFIG_STATUS);
|
|
if (!(val & (1 << 18))) {
|
|
dev_err(priv->dev, "DATA-FPGAs are not enabled\n");
|
|
return -ENODATA;
|
|
}
|
|
|
|
/* read the FPGAs to calculate the buffer size */
|
|
ret = data_calculate_bufsize(priv);
|
|
if (ret) {
|
|
dev_err(priv->dev, "unable to calculate buffer size\n");
|
|
goto out_error;
|
|
}
|
|
|
|
/* allocate the correlation data buffers */
|
|
ret = data_alloc_buffers(priv);
|
|
if (ret) {
|
|
dev_err(priv->dev, "unable to allocate buffers\n");
|
|
goto out_error;
|
|
}
|
|
|
|
/* setup the source scatterlist for dumping correlation data */
|
|
ret = data_setup_corl_table(priv);
|
|
if (ret) {
|
|
dev_err(priv->dev, "unable to setup correlation DMA table\n");
|
|
goto out_error;
|
|
}
|
|
|
|
/* prevent the FPGAs from generating interrupts */
|
|
data_disable_interrupts(priv);
|
|
|
|
/* hookup the irq handler */
|
|
ret = request_irq(priv->irq, data_irq, IRQF_SHARED, drv_name, priv);
|
|
if (ret) {
|
|
dev_err(priv->dev, "unable to request IRQ handler\n");
|
|
goto out_error;
|
|
}
|
|
|
|
/* allow the DMA callback to re-enable FPGA interrupts */
|
|
spin_lock_irq(&priv->lock);
|
|
priv->enabled = true;
|
|
spin_unlock_irq(&priv->lock);
|
|
|
|
/* allow the FPGAs to generate interrupts */
|
|
data_enable_interrupts(priv);
|
|
return 0;
|
|
|
|
out_error:
|
|
sg_free_table(&priv->corl_table);
|
|
priv->corl_nents = 0;
|
|
|
|
data_free_buffers(priv);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* data_device_disable() - disable the device for buffered dumping
|
|
* @priv: the driver's private data structure
|
|
*
|
|
* Disable the device for buffered dumping. Stops new DMA transactions from
|
|
* being generated, waits for all outstanding DMA to complete, and then frees
|
|
* all buffers.
|
|
*
|
|
* LOCKING: must hold dev->mutex
|
|
* CONTEXT: user only
|
|
*
|
|
* Returns 0 on success, -ERRNO otherwise
|
|
*/
|
|
static int data_device_disable(struct fpga_device *priv)
|
|
{
|
|
spin_lock_irq(&priv->lock);
|
|
|
|
/* allow multiple disable */
|
|
if (!priv->enabled) {
|
|
spin_unlock_irq(&priv->lock);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Mark the device disabled
|
|
*
|
|
* This stops DMA callbacks from re-enabling interrupts
|
|
*/
|
|
priv->enabled = false;
|
|
|
|
/* prevent the FPGAs from generating interrupts */
|
|
data_disable_interrupts(priv);
|
|
|
|
/* wait until all ongoing DMA has finished */
|
|
while (priv->inflight != NULL) {
|
|
spin_unlock_irq(&priv->lock);
|
|
wait_event(priv->wait, priv->inflight == NULL);
|
|
spin_lock_irq(&priv->lock);
|
|
}
|
|
|
|
spin_unlock_irq(&priv->lock);
|
|
|
|
/* unhook the irq handler */
|
|
free_irq(priv->irq, priv);
|
|
|
|
/* free the correlation table */
|
|
sg_free_table(&priv->corl_table);
|
|
priv->corl_nents = 0;
|
|
|
|
/* free all buffers: the free and used lists are not being changed */
|
|
data_free_buffers(priv);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* DEBUGFS Interface
|
|
*/
|
|
#ifdef CONFIG_DEBUG_FS
|
|
|
|
/*
|
|
* Count the number of entries in the given list
|
|
*/
|
|
static unsigned int list_num_entries(struct list_head *list)
|
|
{
|
|
struct list_head *entry;
|
|
unsigned int ret = 0;
|
|
|
|
list_for_each(entry, list)
|
|
ret++;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int data_debug_show(struct seq_file *f, void *offset)
|
|
{
|
|
struct fpga_device *priv = f->private;
|
|
|
|
spin_lock_irq(&priv->lock);
|
|
|
|
seq_printf(f, "enabled: %d\n", priv->enabled);
|
|
seq_printf(f, "bufsize: %d\n", priv->bufsize);
|
|
seq_printf(f, "num_buffers: %d\n", priv->num_buffers);
|
|
seq_printf(f, "num_free: %d\n", list_num_entries(&priv->free));
|
|
seq_printf(f, "inflight: %d\n", priv->inflight != NULL);
|
|
seq_printf(f, "num_used: %d\n", list_num_entries(&priv->used));
|
|
seq_printf(f, "num_dropped: %d\n", priv->num_dropped);
|
|
|
|
spin_unlock_irq(&priv->lock);
|
|
return 0;
|
|
}
|
|
|
|
static int data_debug_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, data_debug_show, inode->i_private);
|
|
}
|
|
|
|
static const struct file_operations data_debug_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = data_debug_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
|
|
static int data_debugfs_init(struct fpga_device *priv)
|
|
{
|
|
priv->dbg_entry = debugfs_create_file(drv_name, S_IRUGO, NULL, priv,
|
|
&data_debug_fops);
|
|
return PTR_ERR_OR_ZERO(priv->dbg_entry);
|
|
}
|
|
|
|
static void data_debugfs_exit(struct fpga_device *priv)
|
|
{
|
|
debugfs_remove(priv->dbg_entry);
|
|
}
|
|
|
|
#else
|
|
|
|
static inline int data_debugfs_init(struct fpga_device *priv)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void data_debugfs_exit(struct fpga_device *priv)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_DEBUG_FS */
|
|
|
|
/*
|
|
* SYSFS Attributes
|
|
*/
|
|
|
|
static ssize_t data_en_show(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct fpga_device *priv = dev_get_drvdata(dev);
|
|
int ret;
|
|
|
|
spin_lock_irq(&priv->lock);
|
|
ret = snprintf(buf, PAGE_SIZE, "%u\n", priv->enabled);
|
|
spin_unlock_irq(&priv->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t data_en_set(struct device *dev, struct device_attribute *attr,
|
|
const char *buf, size_t count)
|
|
{
|
|
struct fpga_device *priv = dev_get_drvdata(dev);
|
|
unsigned long enable;
|
|
int ret;
|
|
|
|
ret = kstrtoul(buf, 0, &enable);
|
|
if (ret) {
|
|
dev_err(priv->dev, "unable to parse enable input\n");
|
|
return ret;
|
|
}
|
|
|
|
/* protect against concurrent enable/disable */
|
|
ret = mutex_lock_interruptible(&priv->mutex);
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (enable)
|
|
ret = data_device_enable(priv);
|
|
else
|
|
ret = data_device_disable(priv);
|
|
|
|
if (ret) {
|
|
dev_err(priv->dev, "device %s failed\n",
|
|
enable ? "enable" : "disable");
|
|
count = ret;
|
|
goto out_unlock;
|
|
}
|
|
|
|
out_unlock:
|
|
mutex_unlock(&priv->mutex);
|
|
return count;
|
|
}
|
|
|
|
static DEVICE_ATTR(enable, S_IWUSR | S_IRUGO, data_en_show, data_en_set);
|
|
|
|
static struct attribute *data_sysfs_attrs[] = {
|
|
&dev_attr_enable.attr,
|
|
NULL,
|
|
};
|
|
|
|
static const struct attribute_group rt_sysfs_attr_group = {
|
|
.attrs = data_sysfs_attrs,
|
|
};
|
|
|
|
/*
|
|
* FPGA Realtime Data Character Device
|
|
*/
|
|
|
|
static int data_open(struct inode *inode, struct file *filp)
|
|
{
|
|
/*
|
|
* The miscdevice layer puts our struct miscdevice into the
|
|
* filp->private_data field. We use this to find our private
|
|
* data and then overwrite it with our own private structure.
|
|
*/
|
|
struct fpga_device *priv = container_of(filp->private_data,
|
|
struct fpga_device, miscdev);
|
|
struct fpga_reader *reader;
|
|
int ret;
|
|
|
|
/* allocate private data */
|
|
reader = kzalloc(sizeof(*reader), GFP_KERNEL);
|
|
if (!reader)
|
|
return -ENOMEM;
|
|
|
|
reader->priv = priv;
|
|
reader->buf = NULL;
|
|
|
|
filp->private_data = reader;
|
|
ret = nonseekable_open(inode, filp);
|
|
if (ret) {
|
|
dev_err(priv->dev, "nonseekable-open failed\n");
|
|
kfree(reader);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* success, increase the reference count of the private data structure
|
|
* so that it doesn't disappear if the device is unbound
|
|
*/
|
|
kref_get(&priv->ref);
|
|
return 0;
|
|
}
|
|
|
|
static int data_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct fpga_reader *reader = filp->private_data;
|
|
struct fpga_device *priv = reader->priv;
|
|
|
|
/* free the per-reader structure */
|
|
data_free_buffer(reader->buf);
|
|
kfree(reader);
|
|
filp->private_data = NULL;
|
|
|
|
/* decrement our reference count to the private data */
|
|
kref_put(&priv->ref, fpga_device_release);
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t data_read(struct file *filp, char __user *ubuf, size_t count,
|
|
loff_t *f_pos)
|
|
{
|
|
struct fpga_reader *reader = filp->private_data;
|
|
struct fpga_device *priv = reader->priv;
|
|
struct list_head *used = &priv->used;
|
|
bool drop_buffer = false;
|
|
struct data_buf *dbuf;
|
|
size_t avail;
|
|
void *data;
|
|
int ret;
|
|
|
|
/* check if we already have a partial buffer */
|
|
if (reader->buf) {
|
|
dbuf = reader->buf;
|
|
goto have_buffer;
|
|
}
|
|
|
|
spin_lock_irq(&priv->lock);
|
|
|
|
/* Block until there is at least one buffer on the used list */
|
|
while (list_empty(used)) {
|
|
spin_unlock_irq(&priv->lock);
|
|
|
|
if (filp->f_flags & O_NONBLOCK)
|
|
return -EAGAIN;
|
|
|
|
ret = wait_event_interruptible(priv->wait, !list_empty(used));
|
|
if (ret)
|
|
return ret;
|
|
|
|
spin_lock_irq(&priv->lock);
|
|
}
|
|
|
|
/* Grab the first buffer off of the used list */
|
|
dbuf = list_first_entry(used, struct data_buf, entry);
|
|
list_del_init(&dbuf->entry);
|
|
|
|
spin_unlock_irq(&priv->lock);
|
|
|
|
/* Buffers are always mapped: unmap it */
|
|
carma_dma_unmap(priv->dev, dbuf);
|
|
|
|
/* save the buffer for later */
|
|
reader->buf = dbuf;
|
|
reader->buf_start = 0;
|
|
|
|
have_buffer:
|
|
/* Get the number of bytes available */
|
|
avail = dbuf->size - reader->buf_start;
|
|
data = dbuf->vaddr + reader->buf_start;
|
|
|
|
/* Get the number of bytes we can transfer */
|
|
count = min(count, avail);
|
|
|
|
/* Copy the data to the userspace buffer */
|
|
if (copy_to_user(ubuf, data, count))
|
|
return -EFAULT;
|
|
|
|
/* Update the amount of available space */
|
|
avail -= count;
|
|
|
|
/*
|
|
* If there is still some data available, save the buffer for the
|
|
* next userspace call to read() and return
|
|
*/
|
|
if (avail > 0) {
|
|
reader->buf_start += count;
|
|
reader->buf = dbuf;
|
|
return count;
|
|
}
|
|
|
|
/*
|
|
* Get the buffer ready to be reused for DMA
|
|
*
|
|
* If it fails, we pretend that the read never happed and return
|
|
* -EFAULT to userspace. The read will be retried.
|
|
*/
|
|
ret = carma_dma_map(priv->dev, dbuf);
|
|
if (ret) {
|
|
dev_err(priv->dev, "unable to remap buffer for DMA\n");
|
|
return -EFAULT;
|
|
}
|
|
|
|
/* Lock against concurrent enable/disable */
|
|
spin_lock_irq(&priv->lock);
|
|
|
|
/* the reader is finished with this buffer */
|
|
reader->buf = NULL;
|
|
|
|
/*
|
|
* One of two things has happened, the device is disabled, or the
|
|
* device has been reconfigured underneath us. In either case, we
|
|
* should just throw away the buffer.
|
|
*
|
|
* Lockdep complains if this is done under the spinlock, so we
|
|
* handle it during the unlock path.
|
|
*/
|
|
if (!priv->enabled || dbuf->size != priv->bufsize) {
|
|
drop_buffer = true;
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* The buffer is safe to reuse, so add it back to the free list */
|
|
list_add_tail(&dbuf->entry, &priv->free);
|
|
|
|
out_unlock:
|
|
spin_unlock_irq(&priv->lock);
|
|
|
|
if (drop_buffer) {
|
|
carma_dma_unmap(priv->dev, dbuf);
|
|
data_free_buffer(dbuf);
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
static unsigned int data_poll(struct file *filp, struct poll_table_struct *tbl)
|
|
{
|
|
struct fpga_reader *reader = filp->private_data;
|
|
struct fpga_device *priv = reader->priv;
|
|
unsigned int mask = 0;
|
|
|
|
poll_wait(filp, &priv->wait, tbl);
|
|
|
|
if (!list_empty(&priv->used))
|
|
mask |= POLLIN | POLLRDNORM;
|
|
|
|
return mask;
|
|
}
|
|
|
|
static int data_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
struct fpga_reader *reader = filp->private_data;
|
|
struct fpga_device *priv = reader->priv;
|
|
unsigned long offset, vsize, psize, addr;
|
|
|
|
/* VMA properties */
|
|
offset = vma->vm_pgoff << PAGE_SHIFT;
|
|
vsize = vma->vm_end - vma->vm_start;
|
|
psize = priv->phys_size - offset;
|
|
addr = (priv->phys_addr + offset) >> PAGE_SHIFT;
|
|
|
|
/* Check against the FPGA region's physical memory size */
|
|
if (vsize > psize) {
|
|
dev_err(priv->dev, "requested mmap mapping too large\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
|
|
|
|
return io_remap_pfn_range(vma, vma->vm_start, addr, vsize,
|
|
vma->vm_page_prot);
|
|
}
|
|
|
|
static const struct file_operations data_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = data_open,
|
|
.release = data_release,
|
|
.read = data_read,
|
|
.poll = data_poll,
|
|
.mmap = data_mmap,
|
|
.llseek = no_llseek,
|
|
};
|
|
|
|
/*
|
|
* OpenFirmware Device Subsystem
|
|
*/
|
|
|
|
static bool dma_filter(struct dma_chan *chan, void *data)
|
|
{
|
|
/*
|
|
* DMA Channel #0 is used for the FPGA Programmer, so ignore it
|
|
*
|
|
* This probably won't survive an unload/load cycle of the Freescale
|
|
* DMAEngine driver, but that won't be a problem
|
|
*/
|
|
if (chan->chan_id == 0 && chan->device->dev_id == 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static int data_of_probe(struct platform_device *op)
|
|
{
|
|
struct device_node *of_node = op->dev.of_node;
|
|
struct device *this_device;
|
|
struct fpga_device *priv;
|
|
struct resource res;
|
|
dma_cap_mask_t mask;
|
|
int ret;
|
|
|
|
/* Allocate private data */
|
|
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
|
|
if (!priv) {
|
|
dev_err(&op->dev, "Unable to allocate device private data\n");
|
|
ret = -ENOMEM;
|
|
goto out_return;
|
|
}
|
|
|
|
platform_set_drvdata(op, priv);
|
|
priv->dev = &op->dev;
|
|
kref_init(&priv->ref);
|
|
mutex_init(&priv->mutex);
|
|
|
|
dev_set_drvdata(priv->dev, priv);
|
|
spin_lock_init(&priv->lock);
|
|
INIT_LIST_HEAD(&priv->free);
|
|
INIT_LIST_HEAD(&priv->used);
|
|
init_waitqueue_head(&priv->wait);
|
|
|
|
/* Setup the misc device */
|
|
priv->miscdev.minor = MISC_DYNAMIC_MINOR;
|
|
priv->miscdev.name = drv_name;
|
|
priv->miscdev.fops = &data_fops;
|
|
|
|
/* Get the physical address of the FPGA registers */
|
|
ret = of_address_to_resource(of_node, 0, &res);
|
|
if (ret) {
|
|
dev_err(&op->dev, "Unable to find FPGA physical address\n");
|
|
ret = -ENODEV;
|
|
goto out_free_priv;
|
|
}
|
|
|
|
priv->phys_addr = res.start;
|
|
priv->phys_size = resource_size(&res);
|
|
|
|
/* ioremap the registers for use */
|
|
priv->regs = of_iomap(of_node, 0);
|
|
if (!priv->regs) {
|
|
dev_err(&op->dev, "Unable to ioremap registers\n");
|
|
ret = -ENOMEM;
|
|
goto out_free_priv;
|
|
}
|
|
|
|
dma_cap_zero(mask);
|
|
dma_cap_set(DMA_MEMCPY, mask);
|
|
dma_cap_set(DMA_INTERRUPT, mask);
|
|
dma_cap_set(DMA_SLAVE, mask);
|
|
dma_cap_set(DMA_SG, mask);
|
|
|
|
/* Request a DMA channel */
|
|
priv->chan = dma_request_channel(mask, dma_filter, NULL);
|
|
if (!priv->chan) {
|
|
dev_err(&op->dev, "Unable to request DMA channel\n");
|
|
ret = -ENODEV;
|
|
goto out_unmap_regs;
|
|
}
|
|
|
|
/* Find the correct IRQ number */
|
|
priv->irq = irq_of_parse_and_map(of_node, 0);
|
|
if (priv->irq == NO_IRQ) {
|
|
dev_err(&op->dev, "Unable to find IRQ line\n");
|
|
ret = -ENODEV;
|
|
goto out_release_dma;
|
|
}
|
|
|
|
/* Drive the GPIO for FPGA IRQ high (no interrupt) */
|
|
iowrite32be(IRQ_CORL_DONE, priv->regs + SYS_IRQ_OUTPUT_DATA);
|
|
|
|
/* Register the miscdevice */
|
|
ret = misc_register(&priv->miscdev);
|
|
if (ret) {
|
|
dev_err(&op->dev, "Unable to register miscdevice\n");
|
|
goto out_irq_dispose_mapping;
|
|
}
|
|
|
|
/* Create the debugfs files */
|
|
ret = data_debugfs_init(priv);
|
|
if (ret) {
|
|
dev_err(&op->dev, "Unable to create debugfs files\n");
|
|
goto out_misc_deregister;
|
|
}
|
|
|
|
/* Create the sysfs files */
|
|
this_device = priv->miscdev.this_device;
|
|
dev_set_drvdata(this_device, priv);
|
|
ret = sysfs_create_group(&this_device->kobj, &rt_sysfs_attr_group);
|
|
if (ret) {
|
|
dev_err(&op->dev, "Unable to create sysfs files\n");
|
|
goto out_data_debugfs_exit;
|
|
}
|
|
|
|
dev_info(&op->dev, "CARMA FPGA Realtime Data Driver Loaded\n");
|
|
return 0;
|
|
|
|
out_data_debugfs_exit:
|
|
data_debugfs_exit(priv);
|
|
out_misc_deregister:
|
|
misc_deregister(&priv->miscdev);
|
|
out_irq_dispose_mapping:
|
|
irq_dispose_mapping(priv->irq);
|
|
out_release_dma:
|
|
dma_release_channel(priv->chan);
|
|
out_unmap_regs:
|
|
iounmap(priv->regs);
|
|
out_free_priv:
|
|
kref_put(&priv->ref, fpga_device_release);
|
|
out_return:
|
|
return ret;
|
|
}
|
|
|
|
static int data_of_remove(struct platform_device *op)
|
|
{
|
|
struct fpga_device *priv = platform_get_drvdata(op);
|
|
struct device *this_device = priv->miscdev.this_device;
|
|
|
|
/* remove all sysfs files, now the device cannot be re-enabled */
|
|
sysfs_remove_group(&this_device->kobj, &rt_sysfs_attr_group);
|
|
|
|
/* remove all debugfs files */
|
|
data_debugfs_exit(priv);
|
|
|
|
/* disable the device from generating data */
|
|
data_device_disable(priv);
|
|
|
|
/* remove the character device to stop new readers from appearing */
|
|
misc_deregister(&priv->miscdev);
|
|
|
|
/* cleanup everything not needed by readers */
|
|
irq_dispose_mapping(priv->irq);
|
|
dma_release_channel(priv->chan);
|
|
iounmap(priv->regs);
|
|
|
|
/* release our reference */
|
|
kref_put(&priv->ref, fpga_device_release);
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id data_of_match[] = {
|
|
{ .compatible = "carma,carma-fpga", },
|
|
{},
|
|
};
|
|
|
|
static struct platform_driver data_of_driver = {
|
|
.probe = data_of_probe,
|
|
.remove = data_of_remove,
|
|
.driver = {
|
|
.name = drv_name,
|
|
.of_match_table = data_of_match,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(data_of_driver);
|
|
|
|
MODULE_AUTHOR("Ira W. Snyder <iws@ovro.caltech.edu>");
|
|
MODULE_DESCRIPTION("CARMA DATA-FPGA Access Driver");
|
|
MODULE_LICENSE("GPL");
|