/* * DMA driver for Nvidia's Tegra20 APB DMA controller. * * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "dmaengine.h" #define TEGRA_APBDMA_GENERAL 0x0 #define TEGRA_APBDMA_GENERAL_ENABLE BIT(31) #define TEGRA_APBDMA_CONTROL 0x010 #define TEGRA_APBDMA_IRQ_MASK 0x01c #define TEGRA_APBDMA_IRQ_MASK_SET 0x020 /* CSR register */ #define TEGRA_APBDMA_CHAN_CSR 0x00 #define TEGRA_APBDMA_CSR_ENB BIT(31) #define TEGRA_APBDMA_CSR_IE_EOC BIT(30) #define TEGRA_APBDMA_CSR_HOLD BIT(29) #define TEGRA_APBDMA_CSR_DIR BIT(28) #define TEGRA_APBDMA_CSR_ONCE BIT(27) #define TEGRA_APBDMA_CSR_FLOW BIT(21) #define TEGRA_APBDMA_CSR_REQ_SEL_SHIFT 16 #define TEGRA_APBDMA_CSR_WCOUNT_MASK 0xFFFC /* STATUS register */ #define TEGRA_APBDMA_CHAN_STATUS 0x004 #define TEGRA_APBDMA_STATUS_BUSY BIT(31) #define TEGRA_APBDMA_STATUS_ISE_EOC BIT(30) #define TEGRA_APBDMA_STATUS_HALT BIT(29) #define TEGRA_APBDMA_STATUS_PING_PONG BIT(28) #define TEGRA_APBDMA_STATUS_COUNT_SHIFT 2 #define TEGRA_APBDMA_STATUS_COUNT_MASK 0xFFFC #define TEGRA_APBDMA_CHAN_CSRE 0x00C #define TEGRA_APBDMA_CHAN_CSRE_PAUSE (1 << 31) /* AHB memory address */ #define TEGRA_APBDMA_CHAN_AHBPTR 0x010 /* AHB sequence register */ #define TEGRA_APBDMA_CHAN_AHBSEQ 0x14 #define TEGRA_APBDMA_AHBSEQ_INTR_ENB BIT(31) #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_8 (0 << 28) #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_16 (1 << 28) #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32 (2 << 28) #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_64 (3 << 28) #define TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_128 (4 << 28) #define TEGRA_APBDMA_AHBSEQ_DATA_SWAP BIT(27) #define TEGRA_APBDMA_AHBSEQ_BURST_1 (4 << 24) #define TEGRA_APBDMA_AHBSEQ_BURST_4 (5 << 24) #define TEGRA_APBDMA_AHBSEQ_BURST_8 (6 << 24) #define TEGRA_APBDMA_AHBSEQ_DBL_BUF BIT(19) #define TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT 16 #define TEGRA_APBDMA_AHBSEQ_WRAP_NONE 0 /* APB address */ #define TEGRA_APBDMA_CHAN_APBPTR 0x018 /* APB sequence register */ #define TEGRA_APBDMA_CHAN_APBSEQ 0x01c #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8 (0 << 28) #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16 (1 << 28) #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32 (2 << 28) #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64 (3 << 28) #define TEGRA_APBDMA_APBSEQ_BUS_WIDTH_128 (4 << 28) #define TEGRA_APBDMA_APBSEQ_DATA_SWAP BIT(27) #define TEGRA_APBDMA_APBSEQ_WRAP_WORD_1 (1 << 16) /* * If any burst is in flight and DMA paused then this is the time to complete * on-flight burst and update DMA status register. */ #define TEGRA_APBDMA_BURST_COMPLETE_TIME 20 /* Channel base address offset from APBDMA base address */ #define TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET 0x1000 /* DMA channel register space size */ #define TEGRA_APBDMA_CHANNEL_REGISTER_SIZE 0x20 struct tegra_dma; /* * tegra_dma_chip_data Tegra chip specific DMA data * @nr_channels: Number of channels available in the controller. * @max_dma_count: Maximum DMA transfer count supported by DMA controller. * @support_channel_pause: Support channel wise pause of dma. */ struct tegra_dma_chip_data { int nr_channels; int max_dma_count; bool support_channel_pause; }; /* DMA channel registers */ struct tegra_dma_channel_regs { unsigned long csr; unsigned long ahb_ptr; unsigned long apb_ptr; unsigned long ahb_seq; unsigned long apb_seq; }; /* * tegra_dma_sg_req: Dma request details to configure hardware. This * contains the details for one transfer to configure DMA hw. * The client's request for data transfer can be broken into multiple * sub-transfer as per requester details and hw support. * This sub transfer get added in the list of transfer and point to Tegra * DMA descriptor which manages the transfer details. */ struct tegra_dma_sg_req { struct tegra_dma_channel_regs ch_regs; int req_len; bool configured; bool last_sg; bool half_done; struct list_head node; struct tegra_dma_desc *dma_desc; }; /* * tegra_dma_desc: Tegra DMA descriptors which manages the client requests. * This descriptor keep track of transfer status, callbacks and request * counts etc. */ struct tegra_dma_desc { struct dma_async_tx_descriptor txd; int bytes_requested; int bytes_transferred; enum dma_status dma_status; struct list_head node; struct list_head tx_list; struct list_head cb_node; int cb_count; }; struct tegra_dma_channel; typedef void (*dma_isr_handler)(struct tegra_dma_channel *tdc, bool to_terminate); /* tegra_dma_channel: Channel specific information */ struct tegra_dma_channel { struct dma_chan dma_chan; char name[30]; bool config_init; int id; int irq; unsigned long chan_base_offset; spinlock_t lock; bool busy; struct tegra_dma *tdma; bool cyclic; /* Different lists for managing the requests */ struct list_head free_sg_req; struct list_head pending_sg_req; struct list_head free_dma_desc; struct list_head cb_desc; /* ISR handler and tasklet for bottom half of isr handling */ dma_isr_handler isr_handler; struct tasklet_struct tasklet; dma_async_tx_callback callback; void *callback_param; /* Channel-slave specific configuration */ struct dma_slave_config dma_sconfig; }; /* tegra_dma: Tegra DMA specific information */ struct tegra_dma { struct dma_device dma_dev; struct device *dev; struct clk *dma_clk; spinlock_t global_lock; void __iomem *base_addr; const struct tegra_dma_chip_data *chip_data; /* Some register need to be cache before suspend */ u32 reg_gen; /* Last member of the structure */ struct tegra_dma_channel channels[0]; }; static inline void tdma_write(struct tegra_dma *tdma, u32 reg, u32 val) { writel(val, tdma->base_addr + reg); } static inline u32 tdma_read(struct tegra_dma *tdma, u32 reg) { return readl(tdma->base_addr + reg); } static inline void tdc_write(struct tegra_dma_channel *tdc, u32 reg, u32 val) { writel(val, tdc->tdma->base_addr + tdc->chan_base_offset + reg); } static inline u32 tdc_read(struct tegra_dma_channel *tdc, u32 reg) { return readl(tdc->tdma->base_addr + tdc->chan_base_offset + reg); } static inline struct tegra_dma_channel *to_tegra_dma_chan(struct dma_chan *dc) { return container_of(dc, struct tegra_dma_channel, dma_chan); } static inline struct tegra_dma_desc *txd_to_tegra_dma_desc( struct dma_async_tx_descriptor *td) { return container_of(td, struct tegra_dma_desc, txd); } static inline struct device *tdc2dev(struct tegra_dma_channel *tdc) { return &tdc->dma_chan.dev->device; } static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *tx); static int tegra_dma_runtime_suspend(struct device *dev); static int tegra_dma_runtime_resume(struct device *dev); /* Get DMA desc from free list, if not there then allocate it. */ static struct tegra_dma_desc *tegra_dma_desc_get( struct tegra_dma_channel *tdc) { struct tegra_dma_desc *dma_desc; unsigned long flags; spin_lock_irqsave(&tdc->lock, flags); /* Do not allocate if desc are waiting for ack */ list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { if (async_tx_test_ack(&dma_desc->txd)) { list_del(&dma_desc->node); spin_unlock_irqrestore(&tdc->lock, flags); return dma_desc; } } spin_unlock_irqrestore(&tdc->lock, flags); /* Allocate DMA desc */ dma_desc = kzalloc(sizeof(*dma_desc), GFP_ATOMIC); if (!dma_desc) { dev_err(tdc2dev(tdc), "dma_desc alloc failed\n"); return NULL; } dma_async_tx_descriptor_init(&dma_desc->txd, &tdc->dma_chan); dma_desc->txd.tx_submit = tegra_dma_tx_submit; dma_desc->txd.flags = 0; return dma_desc; } static void tegra_dma_desc_put(struct tegra_dma_channel *tdc, struct tegra_dma_desc *dma_desc) { unsigned long flags; spin_lock_irqsave(&tdc->lock, flags); if (!list_empty(&dma_desc->tx_list)) list_splice_init(&dma_desc->tx_list, &tdc->free_sg_req); list_add_tail(&dma_desc->node, &tdc->free_dma_desc); spin_unlock_irqrestore(&tdc->lock, flags); } static struct tegra_dma_sg_req *tegra_dma_sg_req_get( struct tegra_dma_channel *tdc) { struct tegra_dma_sg_req *sg_req = NULL; unsigned long flags; spin_lock_irqsave(&tdc->lock, flags); if (!list_empty(&tdc->free_sg_req)) { sg_req = list_first_entry(&tdc->free_sg_req, typeof(*sg_req), node); list_del(&sg_req->node); spin_unlock_irqrestore(&tdc->lock, flags); return sg_req; } spin_unlock_irqrestore(&tdc->lock, flags); sg_req = kzalloc(sizeof(struct tegra_dma_sg_req), GFP_ATOMIC); if (!sg_req) dev_err(tdc2dev(tdc), "sg_req alloc failed\n"); return sg_req; } static int tegra_dma_slave_config(struct dma_chan *dc, struct dma_slave_config *sconfig) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); if (!list_empty(&tdc->pending_sg_req)) { dev_err(tdc2dev(tdc), "Configuration not allowed\n"); return -EBUSY; } memcpy(&tdc->dma_sconfig, sconfig, sizeof(*sconfig)); tdc->config_init = true; return 0; } static void tegra_dma_global_pause(struct tegra_dma_channel *tdc, bool wait_for_burst_complete) { struct tegra_dma *tdma = tdc->tdma; spin_lock(&tdma->global_lock); tdma_write(tdma, TEGRA_APBDMA_GENERAL, 0); if (wait_for_burst_complete) udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); } static void tegra_dma_global_resume(struct tegra_dma_channel *tdc) { struct tegra_dma *tdma = tdc->tdma; tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE); spin_unlock(&tdma->global_lock); } static void tegra_dma_pause(struct tegra_dma_channel *tdc, bool wait_for_burst_complete) { struct tegra_dma *tdma = tdc->tdma; if (tdma->chip_data->support_channel_pause) { tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, TEGRA_APBDMA_CHAN_CSRE_PAUSE); if (wait_for_burst_complete) udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); } else { tegra_dma_global_pause(tdc, wait_for_burst_complete); } } static void tegra_dma_resume(struct tegra_dma_channel *tdc) { struct tegra_dma *tdma = tdc->tdma; if (tdma->chip_data->support_channel_pause) { tdc_write(tdc, TEGRA_APBDMA_CHAN_CSRE, 0); } else { tegra_dma_global_resume(tdc); } } static void tegra_dma_stop(struct tegra_dma_channel *tdc) { u32 csr; u32 status; /* Disable interrupts */ csr = tdc_read(tdc, TEGRA_APBDMA_CHAN_CSR); csr &= ~TEGRA_APBDMA_CSR_IE_EOC; tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); /* Disable DMA */ csr &= ~TEGRA_APBDMA_CSR_ENB; tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, csr); /* Clear interrupt status if it is there */ status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { dev_dbg(tdc2dev(tdc), "%s():clearing interrupt\n", __func__); tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); } tdc->busy = false; } static void tegra_dma_start(struct tegra_dma_channel *tdc, struct tegra_dma_sg_req *sg_req) { struct tegra_dma_channel_regs *ch_regs = &sg_req->ch_regs; tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr); tdc_write(tdc, TEGRA_APBDMA_CHAN_APBSEQ, ch_regs->apb_seq); tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, ch_regs->apb_ptr); tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBSEQ, ch_regs->ahb_seq); tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, ch_regs->ahb_ptr); /* Start DMA */ tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, ch_regs->csr | TEGRA_APBDMA_CSR_ENB); } static void tegra_dma_configure_for_next(struct tegra_dma_channel *tdc, struct tegra_dma_sg_req *nsg_req) { unsigned long status; /* * The DMA controller reloads the new configuration for next transfer * after last burst of current transfer completes. * If there is no IEC status then this makes sure that last burst * has not be completed. There may be case that last burst is on * flight and so it can complete but because DMA is paused, it * will not generates interrupt as well as not reload the new * configuration. * If there is already IEC status then interrupt handler need to * load new configuration. */ tegra_dma_pause(tdc, false); status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); /* * If interrupt is pending then do nothing as the ISR will handle * the programing for new request. */ if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { dev_err(tdc2dev(tdc), "Skipping new configuration as interrupt is pending\n"); tegra_dma_resume(tdc); return; } /* Safe to program new configuration */ tdc_write(tdc, TEGRA_APBDMA_CHAN_APBPTR, nsg_req->ch_regs.apb_ptr); tdc_write(tdc, TEGRA_APBDMA_CHAN_AHBPTR, nsg_req->ch_regs.ahb_ptr); tdc_write(tdc, TEGRA_APBDMA_CHAN_CSR, nsg_req->ch_regs.csr | TEGRA_APBDMA_CSR_ENB); nsg_req->configured = true; tegra_dma_resume(tdc); } static void tdc_start_head_req(struct tegra_dma_channel *tdc) { struct tegra_dma_sg_req *sg_req; if (list_empty(&tdc->pending_sg_req)) return; sg_req = list_first_entry(&tdc->pending_sg_req, typeof(*sg_req), node); tegra_dma_start(tdc, sg_req); sg_req->configured = true; tdc->busy = true; } static void tdc_configure_next_head_desc(struct tegra_dma_channel *tdc) { struct tegra_dma_sg_req *hsgreq; struct tegra_dma_sg_req *hnsgreq; if (list_empty(&tdc->pending_sg_req)) return; hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); if (!list_is_last(&hsgreq->node, &tdc->pending_sg_req)) { hnsgreq = list_first_entry(&hsgreq->node, typeof(*hnsgreq), node); tegra_dma_configure_for_next(tdc, hnsgreq); } } static inline int get_current_xferred_count(struct tegra_dma_channel *tdc, struct tegra_dma_sg_req *sg_req, unsigned long status) { return sg_req->req_len - (status & TEGRA_APBDMA_STATUS_COUNT_MASK) - 4; } static void tegra_dma_abort_all(struct tegra_dma_channel *tdc) { struct tegra_dma_sg_req *sgreq; struct tegra_dma_desc *dma_desc; while (!list_empty(&tdc->pending_sg_req)) { sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); list_move_tail(&sgreq->node, &tdc->free_sg_req); if (sgreq->last_sg) { dma_desc = sgreq->dma_desc; dma_desc->dma_status = DMA_ERROR; list_add_tail(&dma_desc->node, &tdc->free_dma_desc); /* Add in cb list if it is not there. */ if (!dma_desc->cb_count) list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); dma_desc->cb_count++; } } tdc->isr_handler = NULL; } static bool handle_continuous_head_request(struct tegra_dma_channel *tdc, struct tegra_dma_sg_req *last_sg_req, bool to_terminate) { struct tegra_dma_sg_req *hsgreq = NULL; if (list_empty(&tdc->pending_sg_req)) { dev_err(tdc2dev(tdc), "Dma is running without req\n"); tegra_dma_stop(tdc); return false; } /* * Check that head req on list should be in flight. * If it is not in flight then abort transfer as * looping of transfer can not continue. */ hsgreq = list_first_entry(&tdc->pending_sg_req, typeof(*hsgreq), node); if (!hsgreq->configured) { tegra_dma_stop(tdc); dev_err(tdc2dev(tdc), "Error in dma transfer, aborting dma\n"); tegra_dma_abort_all(tdc); return false; } /* Configure next request */ if (!to_terminate) tdc_configure_next_head_desc(tdc); return true; } static void handle_once_dma_done(struct tegra_dma_channel *tdc, bool to_terminate) { struct tegra_dma_sg_req *sgreq; struct tegra_dma_desc *dma_desc; tdc->busy = false; sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); dma_desc = sgreq->dma_desc; dma_desc->bytes_transferred += sgreq->req_len; list_del(&sgreq->node); if (sgreq->last_sg) { dma_desc->dma_status = DMA_SUCCESS; dma_cookie_complete(&dma_desc->txd); if (!dma_desc->cb_count) list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); dma_desc->cb_count++; list_add_tail(&dma_desc->node, &tdc->free_dma_desc); } list_add_tail(&sgreq->node, &tdc->free_sg_req); /* Do not start DMA if it is going to be terminate */ if (to_terminate || list_empty(&tdc->pending_sg_req)) return; tdc_start_head_req(tdc); return; } static void handle_cont_sngl_cycle_dma_done(struct tegra_dma_channel *tdc, bool to_terminate) { struct tegra_dma_sg_req *sgreq; struct tegra_dma_desc *dma_desc; bool st; sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); dma_desc = sgreq->dma_desc; dma_desc->bytes_transferred += sgreq->req_len; /* Callback need to be call */ if (!dma_desc->cb_count) list_add_tail(&dma_desc->cb_node, &tdc->cb_desc); dma_desc->cb_count++; /* If not last req then put at end of pending list */ if (!list_is_last(&sgreq->node, &tdc->pending_sg_req)) { list_move_tail(&sgreq->node, &tdc->pending_sg_req); sgreq->configured = false; st = handle_continuous_head_request(tdc, sgreq, to_terminate); if (!st) dma_desc->dma_status = DMA_ERROR; } return; } static void tegra_dma_tasklet(unsigned long data) { struct tegra_dma_channel *tdc = (struct tegra_dma_channel *)data; dma_async_tx_callback callback = NULL; void *callback_param = NULL; struct tegra_dma_desc *dma_desc; unsigned long flags; int cb_count; spin_lock_irqsave(&tdc->lock, flags); while (!list_empty(&tdc->cb_desc)) { dma_desc = list_first_entry(&tdc->cb_desc, typeof(*dma_desc), cb_node); list_del(&dma_desc->cb_node); callback = dma_desc->txd.callback; callback_param = dma_desc->txd.callback_param; cb_count = dma_desc->cb_count; dma_desc->cb_count = 0; spin_unlock_irqrestore(&tdc->lock, flags); while (cb_count-- && callback) callback(callback_param); spin_lock_irqsave(&tdc->lock, flags); } spin_unlock_irqrestore(&tdc->lock, flags); } static irqreturn_t tegra_dma_isr(int irq, void *dev_id) { struct tegra_dma_channel *tdc = dev_id; unsigned long status; unsigned long flags; spin_lock_irqsave(&tdc->lock, flags); status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { tdc_write(tdc, TEGRA_APBDMA_CHAN_STATUS, status); tdc->isr_handler(tdc, false); tasklet_schedule(&tdc->tasklet); spin_unlock_irqrestore(&tdc->lock, flags); return IRQ_HANDLED; } spin_unlock_irqrestore(&tdc->lock, flags); dev_info(tdc2dev(tdc), "Interrupt already served status 0x%08lx\n", status); return IRQ_NONE; } static dma_cookie_t tegra_dma_tx_submit(struct dma_async_tx_descriptor *txd) { struct tegra_dma_desc *dma_desc = txd_to_tegra_dma_desc(txd); struct tegra_dma_channel *tdc = to_tegra_dma_chan(txd->chan); unsigned long flags; dma_cookie_t cookie; spin_lock_irqsave(&tdc->lock, flags); dma_desc->dma_status = DMA_IN_PROGRESS; cookie = dma_cookie_assign(&dma_desc->txd); list_splice_tail_init(&dma_desc->tx_list, &tdc->pending_sg_req); spin_unlock_irqrestore(&tdc->lock, flags); return cookie; } static void tegra_dma_issue_pending(struct dma_chan *dc) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); unsigned long flags; spin_lock_irqsave(&tdc->lock, flags); if (list_empty(&tdc->pending_sg_req)) { dev_err(tdc2dev(tdc), "No DMA request\n"); goto end; } if (!tdc->busy) { tdc_start_head_req(tdc); /* Continuous single mode: Configure next req */ if (tdc->cyclic) { /* * Wait for 1 burst time for configure DMA for * next transfer. */ udelay(TEGRA_APBDMA_BURST_COMPLETE_TIME); tdc_configure_next_head_desc(tdc); } } end: spin_unlock_irqrestore(&tdc->lock, flags); return; } static void tegra_dma_terminate_all(struct dma_chan *dc) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); struct tegra_dma_sg_req *sgreq; struct tegra_dma_desc *dma_desc; unsigned long flags; unsigned long status; bool was_busy; spin_lock_irqsave(&tdc->lock, flags); if (list_empty(&tdc->pending_sg_req)) { spin_unlock_irqrestore(&tdc->lock, flags); return; } if (!tdc->busy) goto skip_dma_stop; /* Pause DMA before checking the queue status */ tegra_dma_pause(tdc, true); status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); if (status & TEGRA_APBDMA_STATUS_ISE_EOC) { dev_dbg(tdc2dev(tdc), "%s():handling isr\n", __func__); tdc->isr_handler(tdc, true); status = tdc_read(tdc, TEGRA_APBDMA_CHAN_STATUS); } was_busy = tdc->busy; tegra_dma_stop(tdc); if (!list_empty(&tdc->pending_sg_req) && was_busy) { sgreq = list_first_entry(&tdc->pending_sg_req, typeof(*sgreq), node); sgreq->dma_desc->bytes_transferred += get_current_xferred_count(tdc, sgreq, status); } tegra_dma_resume(tdc); skip_dma_stop: tegra_dma_abort_all(tdc); while (!list_empty(&tdc->cb_desc)) { dma_desc = list_first_entry(&tdc->cb_desc, typeof(*dma_desc), cb_node); list_del(&dma_desc->cb_node); dma_desc->cb_count = 0; } spin_unlock_irqrestore(&tdc->lock, flags); } static enum dma_status tegra_dma_tx_status(struct dma_chan *dc, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); struct tegra_dma_desc *dma_desc; struct tegra_dma_sg_req *sg_req; enum dma_status ret; unsigned long flags; unsigned int residual; spin_lock_irqsave(&tdc->lock, flags); ret = dma_cookie_status(dc, cookie, txstate); if (ret == DMA_SUCCESS) { dma_set_residue(txstate, 0); spin_unlock_irqrestore(&tdc->lock, flags); return ret; } /* Check on wait_ack desc status */ list_for_each_entry(dma_desc, &tdc->free_dma_desc, node) { if (dma_desc->txd.cookie == cookie) { residual = dma_desc->bytes_requested - (dma_desc->bytes_transferred % dma_desc->bytes_requested); dma_set_residue(txstate, residual); ret = dma_desc->dma_status; spin_unlock_irqrestore(&tdc->lock, flags); return ret; } } /* Check in pending list */ list_for_each_entry(sg_req, &tdc->pending_sg_req, node) { dma_desc = sg_req->dma_desc; if (dma_desc->txd.cookie == cookie) { residual = dma_desc->bytes_requested - (dma_desc->bytes_transferred % dma_desc->bytes_requested); dma_set_residue(txstate, residual); ret = dma_desc->dma_status; spin_unlock_irqrestore(&tdc->lock, flags); return ret; } } dev_dbg(tdc2dev(tdc), "cookie %d does not found\n", cookie); spin_unlock_irqrestore(&tdc->lock, flags); return ret; } static int tegra_dma_device_control(struct dma_chan *dc, enum dma_ctrl_cmd cmd, unsigned long arg) { switch (cmd) { case DMA_SLAVE_CONFIG: return tegra_dma_slave_config(dc, (struct dma_slave_config *)arg); case DMA_TERMINATE_ALL: tegra_dma_terminate_all(dc); return 0; default: break; } return -ENXIO; } static inline int get_bus_width(struct tegra_dma_channel *tdc, enum dma_slave_buswidth slave_bw) { switch (slave_bw) { case DMA_SLAVE_BUSWIDTH_1_BYTE: return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_8; case DMA_SLAVE_BUSWIDTH_2_BYTES: return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_16; case DMA_SLAVE_BUSWIDTH_4_BYTES: return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; case DMA_SLAVE_BUSWIDTH_8_BYTES: return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_64; default: dev_warn(tdc2dev(tdc), "slave bw is not supported, using 32bits\n"); return TEGRA_APBDMA_APBSEQ_BUS_WIDTH_32; } } static inline int get_burst_size(struct tegra_dma_channel *tdc, u32 burst_size, enum dma_slave_buswidth slave_bw, int len) { int burst_byte; int burst_ahb_width; /* * burst_size from client is in terms of the bus_width. * convert them into AHB memory width which is 4 byte. */ burst_byte = burst_size * slave_bw; burst_ahb_width = burst_byte / 4; /* If burst size is 0 then calculate the burst size based on length */ if (!burst_ahb_width) { if (len & 0xF) return TEGRA_APBDMA_AHBSEQ_BURST_1; else if ((len >> 4) & 0x1) return TEGRA_APBDMA_AHBSEQ_BURST_4; else return TEGRA_APBDMA_AHBSEQ_BURST_8; } if (burst_ahb_width < 4) return TEGRA_APBDMA_AHBSEQ_BURST_1; else if (burst_ahb_width < 8) return TEGRA_APBDMA_AHBSEQ_BURST_4; else return TEGRA_APBDMA_AHBSEQ_BURST_8; } static int get_transfer_param(struct tegra_dma_channel *tdc, enum dma_transfer_direction direction, unsigned long *apb_addr, unsigned long *apb_seq, unsigned long *csr, unsigned int *burst_size, enum dma_slave_buswidth *slave_bw) { switch (direction) { case DMA_MEM_TO_DEV: *apb_addr = tdc->dma_sconfig.dst_addr; *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.dst_addr_width); *burst_size = tdc->dma_sconfig.dst_maxburst; *slave_bw = tdc->dma_sconfig.dst_addr_width; *csr = TEGRA_APBDMA_CSR_DIR; return 0; case DMA_DEV_TO_MEM: *apb_addr = tdc->dma_sconfig.src_addr; *apb_seq = get_bus_width(tdc, tdc->dma_sconfig.src_addr_width); *burst_size = tdc->dma_sconfig.src_maxburst; *slave_bw = tdc->dma_sconfig.src_addr_width; *csr = 0; return 0; default: dev_err(tdc2dev(tdc), "Dma direction is not supported\n"); return -EINVAL; } return -EINVAL; } static struct dma_async_tx_descriptor *tegra_dma_prep_slave_sg( struct dma_chan *dc, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); struct tegra_dma_desc *dma_desc; unsigned int i; struct scatterlist *sg; unsigned long csr, ahb_seq, apb_ptr, apb_seq; struct list_head req_list; struct tegra_dma_sg_req *sg_req = NULL; u32 burst_size; enum dma_slave_buswidth slave_bw; int ret; if (!tdc->config_init) { dev_err(tdc2dev(tdc), "dma channel is not configured\n"); return NULL; } if (sg_len < 1) { dev_err(tdc2dev(tdc), "Invalid segment length %d\n", sg_len); return NULL; } ret = get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, &burst_size, &slave_bw); if (ret < 0) return NULL; INIT_LIST_HEAD(&req_list); ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; csr |= TEGRA_APBDMA_CSR_ONCE | TEGRA_APBDMA_CSR_FLOW; csr |= tdc->dma_sconfig.slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; if (flags & DMA_PREP_INTERRUPT) csr |= TEGRA_APBDMA_CSR_IE_EOC; apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; dma_desc = tegra_dma_desc_get(tdc); if (!dma_desc) { dev_err(tdc2dev(tdc), "Dma descriptors not available\n"); return NULL; } INIT_LIST_HEAD(&dma_desc->tx_list); INIT_LIST_HEAD(&dma_desc->cb_node); dma_desc->cb_count = 0; dma_desc->bytes_requested = 0; dma_desc->bytes_transferred = 0; dma_desc->dma_status = DMA_IN_PROGRESS; /* Make transfer requests */ for_each_sg(sgl, sg, sg_len, i) { u32 len, mem; mem = sg_dma_address(sg); len = sg_dma_len(sg); if ((len & 3) || (mem & 3) || (len > tdc->tdma->chip_data->max_dma_count)) { dev_err(tdc2dev(tdc), "Dma length/memory address is not supported\n"); tegra_dma_desc_put(tdc, dma_desc); return NULL; } sg_req = tegra_dma_sg_req_get(tdc); if (!sg_req) { dev_err(tdc2dev(tdc), "Dma sg-req not available\n"); tegra_dma_desc_put(tdc, dma_desc); return NULL; } ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); dma_desc->bytes_requested += len; sg_req->ch_regs.apb_ptr = apb_ptr; sg_req->ch_regs.ahb_ptr = mem; sg_req->ch_regs.csr = csr | ((len - 4) & 0xFFFC); sg_req->ch_regs.apb_seq = apb_seq; sg_req->ch_regs.ahb_seq = ahb_seq; sg_req->configured = false; sg_req->last_sg = false; sg_req->dma_desc = dma_desc; sg_req->req_len = len; list_add_tail(&sg_req->node, &dma_desc->tx_list); } sg_req->last_sg = true; if (flags & DMA_CTRL_ACK) dma_desc->txd.flags = DMA_CTRL_ACK; /* * Make sure that mode should not be conflicting with currently * configured mode. */ if (!tdc->isr_handler) { tdc->isr_handler = handle_once_dma_done; tdc->cyclic = false; } else { if (tdc->cyclic) { dev_err(tdc2dev(tdc), "DMA configured in cyclic mode\n"); tegra_dma_desc_put(tdc, dma_desc); return NULL; } } return &dma_desc->txd; } struct dma_async_tx_descriptor *tegra_dma_prep_dma_cyclic( struct dma_chan *dc, dma_addr_t buf_addr, size_t buf_len, size_t period_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); struct tegra_dma_desc *dma_desc = NULL; struct tegra_dma_sg_req *sg_req = NULL; unsigned long csr, ahb_seq, apb_ptr, apb_seq; int len; size_t remain_len; dma_addr_t mem = buf_addr; u32 burst_size; enum dma_slave_buswidth slave_bw; int ret; if (!buf_len || !period_len) { dev_err(tdc2dev(tdc), "Invalid buffer/period len\n"); return NULL; } if (!tdc->config_init) { dev_err(tdc2dev(tdc), "DMA slave is not configured\n"); return NULL; } /* * We allow to take more number of requests till DMA is * not started. The driver will loop over all requests. * Once DMA is started then new requests can be queued only after * terminating the DMA. */ if (tdc->busy) { dev_err(tdc2dev(tdc), "Request not allowed when dma running\n"); return NULL; } /* * We only support cycle transfer when buf_len is multiple of * period_len. */ if (buf_len % period_len) { dev_err(tdc2dev(tdc), "buf_len is not multiple of period_len\n"); return NULL; } len = period_len; if ((len & 3) || (buf_addr & 3) || (len > tdc->tdma->chip_data->max_dma_count)) { dev_err(tdc2dev(tdc), "Req len/mem address is not correct\n"); return NULL; } ret = get_transfer_param(tdc, direction, &apb_ptr, &apb_seq, &csr, &burst_size, &slave_bw); if (ret < 0) return NULL; ahb_seq = TEGRA_APBDMA_AHBSEQ_INTR_ENB; ahb_seq |= TEGRA_APBDMA_AHBSEQ_WRAP_NONE << TEGRA_APBDMA_AHBSEQ_WRAP_SHIFT; ahb_seq |= TEGRA_APBDMA_AHBSEQ_BUS_WIDTH_32; csr |= TEGRA_APBDMA_CSR_FLOW | TEGRA_APBDMA_CSR_IE_EOC; csr |= tdc->dma_sconfig.slave_id << TEGRA_APBDMA_CSR_REQ_SEL_SHIFT; apb_seq |= TEGRA_APBDMA_APBSEQ_WRAP_WORD_1; dma_desc = tegra_dma_desc_get(tdc); if (!dma_desc) { dev_err(tdc2dev(tdc), "not enough descriptors available\n"); return NULL; } INIT_LIST_HEAD(&dma_desc->tx_list); INIT_LIST_HEAD(&dma_desc->cb_node); dma_desc->cb_count = 0; dma_desc->bytes_transferred = 0; dma_desc->bytes_requested = buf_len; remain_len = buf_len; /* Split transfer equal to period size */ while (remain_len) { sg_req = tegra_dma_sg_req_get(tdc); if (!sg_req) { dev_err(tdc2dev(tdc), "Dma sg-req not available\n"); tegra_dma_desc_put(tdc, dma_desc); return NULL; } ahb_seq |= get_burst_size(tdc, burst_size, slave_bw, len); sg_req->ch_regs.apb_ptr = apb_ptr; sg_req->ch_regs.ahb_ptr = mem; sg_req->ch_regs.csr = csr | ((len - 4) & 0xFFFC); sg_req->ch_regs.apb_seq = apb_seq; sg_req->ch_regs.ahb_seq = ahb_seq; sg_req->configured = false; sg_req->half_done = false; sg_req->last_sg = false; sg_req->dma_desc = dma_desc; sg_req->req_len = len; list_add_tail(&sg_req->node, &dma_desc->tx_list); remain_len -= len; mem += len; } sg_req->last_sg = true; dma_desc->txd.flags = 0; /* * Make sure that mode should not be conflicting with currently * configured mode. */ if (!tdc->isr_handler) { tdc->isr_handler = handle_cont_sngl_cycle_dma_done; tdc->cyclic = true; } else { if (!tdc->cyclic) { dev_err(tdc2dev(tdc), "DMA configuration conflict\n"); tegra_dma_desc_put(tdc, dma_desc); return NULL; } } return &dma_desc->txd; } static int tegra_dma_alloc_chan_resources(struct dma_chan *dc) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); struct tegra_dma *tdma = tdc->tdma; int ret; dma_cookie_init(&tdc->dma_chan); tdc->config_init = false; ret = clk_prepare_enable(tdma->dma_clk); if (ret < 0) dev_err(tdc2dev(tdc), "clk_prepare_enable failed: %d\n", ret); return ret; } static void tegra_dma_free_chan_resources(struct dma_chan *dc) { struct tegra_dma_channel *tdc = to_tegra_dma_chan(dc); struct tegra_dma *tdma = tdc->tdma; struct tegra_dma_desc *dma_desc; struct tegra_dma_sg_req *sg_req; struct list_head dma_desc_list; struct list_head sg_req_list; unsigned long flags; INIT_LIST_HEAD(&dma_desc_list); INIT_LIST_HEAD(&sg_req_list); dev_dbg(tdc2dev(tdc), "Freeing channel %d\n", tdc->id); if (tdc->busy) tegra_dma_terminate_all(dc); spin_lock_irqsave(&tdc->lock, flags); list_splice_init(&tdc->pending_sg_req, &sg_req_list); list_splice_init(&tdc->free_sg_req, &sg_req_list); list_splice_init(&tdc->free_dma_desc, &dma_desc_list); INIT_LIST_HEAD(&tdc->cb_desc); tdc->config_init = false; spin_unlock_irqrestore(&tdc->lock, flags); while (!list_empty(&dma_desc_list)) { dma_desc = list_first_entry(&dma_desc_list, typeof(*dma_desc), node); list_del(&dma_desc->node); kfree(dma_desc); } while (!list_empty(&sg_req_list)) { sg_req = list_first_entry(&sg_req_list, typeof(*sg_req), node); list_del(&sg_req->node); kfree(sg_req); } clk_disable_unprepare(tdma->dma_clk); } /* Tegra20 specific DMA controller information */ static const struct tegra_dma_chip_data tegra20_dma_chip_data = { .nr_channels = 16, .max_dma_count = 1024UL * 64, .support_channel_pause = false, }; #if defined(CONFIG_OF) /* Tegra30 specific DMA controller information */ static const struct tegra_dma_chip_data tegra30_dma_chip_data = { .nr_channels = 32, .max_dma_count = 1024UL * 64, .support_channel_pause = false, }; static const struct of_device_id tegra_dma_of_match[] __devinitconst = { { .compatible = "nvidia,tegra30-apbdma", .data = &tegra30_dma_chip_data, }, { .compatible = "nvidia,tegra20-apbdma", .data = &tegra20_dma_chip_data, }, { }, }; MODULE_DEVICE_TABLE(of, tegra_dma_of_match); #endif static int tegra_dma_probe(struct platform_device *pdev) { struct resource *res; struct tegra_dma *tdma; int ret; int i; const struct tegra_dma_chip_data *cdata = NULL; if (pdev->dev.of_node) { const struct of_device_id *match; match = of_match_device(of_match_ptr(tegra_dma_of_match), &pdev->dev); if (!match) { dev_err(&pdev->dev, "Error: No device match found\n"); return -ENODEV; } cdata = match->data; } else { /* If no device tree then fallback to tegra20 */ cdata = &tegra20_dma_chip_data; } tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels * sizeof(struct tegra_dma_channel), GFP_KERNEL); if (!tdma) { dev_err(&pdev->dev, "Error: memory allocation failed\n"); return -ENOMEM; } tdma->dev = &pdev->dev; tdma->chip_data = cdata; platform_set_drvdata(pdev, tdma); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(&pdev->dev, "No mem resource for DMA\n"); return -EINVAL; } tdma->base_addr = devm_request_and_ioremap(&pdev->dev, res); if (!tdma->base_addr) { dev_err(&pdev->dev, "Cannot request memregion/iomap dma address\n"); return -EADDRNOTAVAIL; } tdma->dma_clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(tdma->dma_clk)) { dev_err(&pdev->dev, "Error: Missing controller clock\n"); return PTR_ERR(tdma->dma_clk); } spin_lock_init(&tdma->global_lock); pm_runtime_enable(&pdev->dev); if (!pm_runtime_enabled(&pdev->dev)) { ret = tegra_dma_runtime_resume(&pdev->dev); if (ret) { dev_err(&pdev->dev, "dma_runtime_resume failed %d\n", ret); goto err_pm_disable; } } /* Enable clock before accessing registers */ ret = clk_prepare_enable(tdma->dma_clk); if (ret < 0) { dev_err(&pdev->dev, "clk_prepare_enable failed: %d\n", ret); goto err_pm_disable; } /* Reset DMA controller */ tegra_periph_reset_assert(tdma->dma_clk); udelay(2); tegra_periph_reset_deassert(tdma->dma_clk); /* Enable global DMA registers */ tdma_write(tdma, TEGRA_APBDMA_GENERAL, TEGRA_APBDMA_GENERAL_ENABLE); tdma_write(tdma, TEGRA_APBDMA_CONTROL, 0); tdma_write(tdma, TEGRA_APBDMA_IRQ_MASK_SET, 0xFFFFFFFFul); clk_disable_unprepare(tdma->dma_clk); INIT_LIST_HEAD(&tdma->dma_dev.channels); for (i = 0; i < cdata->nr_channels; i++) { struct tegra_dma_channel *tdc = &tdma->channels[i]; tdc->chan_base_offset = TEGRA_APBDMA_CHANNEL_BASE_ADD_OFFSET + i * TEGRA_APBDMA_CHANNEL_REGISTER_SIZE; res = platform_get_resource(pdev, IORESOURCE_IRQ, i); if (!res) { ret = -EINVAL; dev_err(&pdev->dev, "No irq resource for chan %d\n", i); goto err_irq; } tdc->irq = res->start; snprintf(tdc->name, sizeof(tdc->name), "apbdma.%d", i); ret = devm_request_irq(&pdev->dev, tdc->irq, tegra_dma_isr, 0, tdc->name, tdc); if (ret) { dev_err(&pdev->dev, "request_irq failed with err %d channel %d\n", i, ret); goto err_irq; } tdc->dma_chan.device = &tdma->dma_dev; dma_cookie_init(&tdc->dma_chan); list_add_tail(&tdc->dma_chan.device_node, &tdma->dma_dev.channels); tdc->tdma = tdma; tdc->id = i; tasklet_init(&tdc->tasklet, tegra_dma_tasklet, (unsigned long)tdc); spin_lock_init(&tdc->lock); INIT_LIST_HEAD(&tdc->pending_sg_req); INIT_LIST_HEAD(&tdc->free_sg_req); INIT_LIST_HEAD(&tdc->free_dma_desc); INIT_LIST_HEAD(&tdc->cb_desc); } dma_cap_set(DMA_SLAVE, tdma->dma_dev.cap_mask); dma_cap_set(DMA_PRIVATE, tdma->dma_dev.cap_mask); dma_cap_set(DMA_CYCLIC, tdma->dma_dev.cap_mask); tdma->dma_dev.dev = &pdev->dev; tdma->dma_dev.device_alloc_chan_resources = tegra_dma_alloc_chan_resources; tdma->dma_dev.device_free_chan_resources = tegra_dma_free_chan_resources; tdma->dma_dev.device_prep_slave_sg = tegra_dma_prep_slave_sg; tdma->dma_dev.device_prep_dma_cyclic = tegra_dma_prep_dma_cyclic; tdma->dma_dev.device_control = tegra_dma_device_control; tdma->dma_dev.device_tx_status = tegra_dma_tx_status; tdma->dma_dev.device_issue_pending = tegra_dma_issue_pending; ret = dma_async_device_register(&tdma->dma_dev); if (ret < 0) { dev_err(&pdev->dev, "Tegra20 APB DMA driver registration failed %d\n", ret); goto err_irq; } dev_info(&pdev->dev, "Tegra20 APB DMA driver register %d channels\n", cdata->nr_channels); return 0; err_irq: while (--i >= 0) { struct tegra_dma_channel *tdc = &tdma->channels[i]; tasklet_kill(&tdc->tasklet); } err_pm_disable: pm_runtime_disable(&pdev->dev); if (!pm_runtime_status_suspended(&pdev->dev)) tegra_dma_runtime_suspend(&pdev->dev); return ret; } static int __devexit tegra_dma_remove(struct platform_device *pdev) { struct tegra_dma *tdma = platform_get_drvdata(pdev); int i; struct tegra_dma_channel *tdc; dma_async_device_unregister(&tdma->dma_dev); for (i = 0; i < tdma->chip_data->nr_channels; ++i) { tdc = &tdma->channels[i]; tasklet_kill(&tdc->tasklet); } pm_runtime_disable(&pdev->dev); if (!pm_runtime_status_suspended(&pdev->dev)) tegra_dma_runtime_suspend(&pdev->dev); return 0; } static int tegra_dma_runtime_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct tegra_dma *tdma = platform_get_drvdata(pdev); clk_disable_unprepare(tdma->dma_clk); return 0; } static int tegra_dma_runtime_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct tegra_dma *tdma = platform_get_drvdata(pdev); int ret; ret = clk_prepare_enable(tdma->dma_clk); if (ret < 0) { dev_err(dev, "clk_enable failed: %d\n", ret); return ret; } return 0; } static const struct dev_pm_ops tegra_dma_dev_pm_ops __devinitconst = { #ifdef CONFIG_PM_RUNTIME .runtime_suspend = tegra_dma_runtime_suspend, .runtime_resume = tegra_dma_runtime_resume, #endif }; static struct platform_driver tegra_dmac_driver = { .driver = { .name = "tegra-apbdma", .owner = THIS_MODULE, .pm = &tegra_dma_dev_pm_ops, .of_match_table = of_match_ptr(tegra_dma_of_match), }, .probe = tegra_dma_probe, .remove = tegra_dma_remove, }; module_platform_driver(tegra_dmac_driver); MODULE_ALIAS("platform:tegra20-apbdma"); MODULE_DESCRIPTION("NVIDIA Tegra APB DMA Controller driver"); MODULE_AUTHOR("Laxman Dewangan "); MODULE_LICENSE("GPL v2");