linux/arch/arm/mach-omap2/dma.c

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/*
* OMAP2+ DMA driver
*
* Copyright (C) 2003 - 2008 Nokia Corporation
* Author: Juha Yrjölä <juha.yrjola@nokia.com>
* DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com>
* Graphics DMA and LCD DMA graphics tranformations
* by Imre Deak <imre.deak@nokia.com>
* OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc.
* Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc.
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
* Converted DMA library into platform driver
* - G, Manjunath Kondaiah <manjugk@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/of.h>
ARM: OMAP: Move plat-omap/dma-omap.h to include/linux/omap-dma.h Based on earlier discussions[1] we attempted to find a suitable location for the omap DMA header in commit 2b6c4e73 (ARM: OMAP: DMA: Move plat/dma.h to plat-omap/dma-omap.h) until the conversion to dmaengine is complete. Unfortunately that was before I was able to try to test compile of the ARM multiplatform builds for omap2+, and the end result was not very good. So I'm creating yet another all over the place patch to cut the last dependency for building omap2+ for ARM multiplatform. After this, we have finally removed the driver dependencies to the arch/arm code, except for few drivers that are being worked on. The other option was to make the <plat-omap/dma-omap.h> path to work, but we'd have to add some new header directory to for multiplatform builds. Or we would have to manually include arch/arm/plat-omap/include again from arch/arm/Makefile for omap2+. Neither of these alternatives sound appealing as they will likely lead addition of various other headers exposed to the drivers, which we want to avoid for the multiplatform kernels. Since we already have a minimal include/linux/omap-dma.h, let's just use that instead and add a note to it to not use the custom omap DMA functions any longer where possible. Note that converting omap DMA to dmaengine depends on dmaengine supporting automatically incrementing the FIFO address at the device end, and converting all the remaining legacy drivers. So it's going to be few more merge windows. [1] https://patchwork.kernel.org/patch/1519591/# cc: Russell King <linux@arm.linux.org.uk> cc: Kevin Hilman <khilman@ti.com> cc: "Benoît Cousson" <b-cousson@ti.com> cc: Herbert Xu <herbert@gondor.apana.org.au> cc: "David S. Miller" <davem@davemloft.net> cc: Vinod Koul <vinod.koul@intel.com> cc: Dan Williams <djbw@fb.com> cc: Mauro Carvalho Chehab <mchehab@infradead.org> cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> cc: David Woodhouse <dwmw2@infradead.org> cc: Kyungmin Park <kyungmin.park@samsung.com> cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> cc: Tomi Valkeinen <tomi.valkeinen@ti.com> cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> cc: Hans Verkuil <hans.verkuil@cisco.com> cc: Vaibhav Hiremath <hvaibhav@ti.com> cc: Lokesh Vutla <lokeshvutla@ti.com> cc: Rusty Russell <rusty@rustcorp.com.au> cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> cc: Afzal Mohammed <afzal@ti.com> cc: linux-crypto@vger.kernel.org cc: linux-media@vger.kernel.org cc: linux-mtd@lists.infradead.org cc: linux-usb@vger.kernel.org cc: linux-fbdev@vger.kernel.org Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
2012-12-01 00:41:50 +08:00
#include <linux/omap-dma.h>
#include "soc.h"
#include "omap_hwmod.h"
#include "omap_device.h"
#define OMAP2_DMA_STRIDE 0x60
static u32 errata;
static u8 dma_stride;
static struct omap_dma_dev_attr *d;
static enum omap_reg_offsets dma_common_ch_start, dma_common_ch_end;
static u16 reg_map[] = {
[REVISION] = 0x00,
[GCR] = 0x78,
[IRQSTATUS_L0] = 0x08,
[IRQSTATUS_L1] = 0x0c,
[IRQSTATUS_L2] = 0x10,
[IRQSTATUS_L3] = 0x14,
[IRQENABLE_L0] = 0x18,
[IRQENABLE_L1] = 0x1c,
[IRQENABLE_L2] = 0x20,
[IRQENABLE_L3] = 0x24,
[SYSSTATUS] = 0x28,
[OCP_SYSCONFIG] = 0x2c,
[CAPS_0] = 0x64,
[CAPS_2] = 0x6c,
[CAPS_3] = 0x70,
[CAPS_4] = 0x74,
/* Common register offsets */
[CCR] = 0x80,
[CLNK_CTRL] = 0x84,
[CICR] = 0x88,
[CSR] = 0x8c,
[CSDP] = 0x90,
[CEN] = 0x94,
[CFN] = 0x98,
[CSEI] = 0xa4,
[CSFI] = 0xa8,
[CDEI] = 0xac,
[CDFI] = 0xb0,
[CSAC] = 0xb4,
[CDAC] = 0xb8,
/* Channel specific register offsets */
[CSSA] = 0x9c,
[CDSA] = 0xa0,
[CCEN] = 0xbc,
[CCFN] = 0xc0,
[COLOR] = 0xc4,
/* OMAP4 specific registers */
[CDP] = 0xd0,
[CNDP] = 0xd4,
[CCDN] = 0xd8,
};
static void __iomem *dma_base;
static inline void dma_write(u32 val, int reg, int lch)
{
u8 stride;
u32 offset;
stride = (reg >= dma_common_ch_start) ? dma_stride : 0;
offset = reg_map[reg] + (stride * lch);
__raw_writel(val, dma_base + offset);
}
static inline u32 dma_read(int reg, int lch)
{
u8 stride;
u32 offset, val;
stride = (reg >= dma_common_ch_start) ? dma_stride : 0;
offset = reg_map[reg] + (stride * lch);
val = __raw_readl(dma_base + offset);
return val;
}
static inline void omap2_disable_irq_lch(int lch)
{
u32 val;
val = dma_read(IRQENABLE_L0, lch);
val &= ~(1 << lch);
dma_write(val, IRQENABLE_L0, lch);
}
static void omap2_clear_dma(int lch)
{
int i = dma_common_ch_start;
for (; i <= dma_common_ch_end; i += 1)
dma_write(0, i, lch);
}
static void omap2_show_dma_caps(void)
{
u8 revision = dma_read(REVISION, 0) & 0xff;
printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n",
revision >> 4, revision & 0xf);
return;
}
static u32 configure_dma_errata(void)
{
/*
* Errata applicable for OMAP2430ES1.0 and all omap2420
*
* I.
* Erratum ID: Not Available
* Inter Frame DMA buffering issue DMA will wrongly
* buffer elements if packing and bursting is enabled. This might
* result in data gets stalled in FIFO at the end of the block.
* Workaround: DMA channels must have BUFFERING_DISABLED bit set to
* guarantee no data will stay in the DMA FIFO in case inter frame
* buffering occurs
*
* II.
* Erratum ID: Not Available
* DMA may hang when several channels are used in parallel
* In the following configuration, DMA channel hanging can occur:
* a. Channel i, hardware synchronized, is enabled
* b. Another channel (Channel x), software synchronized, is enabled.
* c. Channel i is disabled before end of transfer
* d. Channel i is reenabled.
* e. Steps 1 to 4 are repeated a certain number of times.
* f. A third channel (Channel y), software synchronized, is enabled.
* Channel x and Channel y may hang immediately after step 'f'.
* Workaround:
* For any channel used - make sure NextLCH_ID is set to the value j.
*/
if (cpu_is_omap2420() || (cpu_is_omap2430() &&
(omap_type() == OMAP2430_REV_ES1_0))) {
SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING);
SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS);
}
/*
* Erratum ID: i378: OMAP2+: sDMA Channel is not disabled
* after a transaction error.
* Workaround: SW should explicitely disable the channel.
*/
if (cpu_class_is_omap2())
SET_DMA_ERRATA(DMA_ERRATA_i378);
/*
* Erratum ID: i541: sDMA FIFO draining does not finish
* If sDMA channel is disabled on the fly, sDMA enters standby even
* through FIFO Drain is still in progress
* Workaround: Put sDMA in NoStandby more before a logical channel is
* disabled, then put it back to SmartStandby right after the channel
* finishes FIFO draining.
*/
if (cpu_is_omap34xx())
SET_DMA_ERRATA(DMA_ERRATA_i541);
/*
* Erratum ID: i88 : Special programming model needed to disable DMA
* before end of block.
* Workaround: software must ensure that the DMA is configured in No
* Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01")
*/
if (omap_type() == OMAP3430_REV_ES1_0)
SET_DMA_ERRATA(DMA_ERRATA_i88);
/*
* Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
* read before the DMA controller finished disabling the channel.
*/
SET_DMA_ERRATA(DMA_ERRATA_3_3);
/*
* Erratum ID: Not Available
* A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared
* after secure sram context save and restore.
* Work around: Hence we need to manually clear those IRQs to avoid
* spurious interrupts. This affects only secure devices.
*/
if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
SET_DMA_ERRATA(DMA_ROMCODE_BUG);
return errata;
}
/* One time initializations */
static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
{
struct platform_device *pdev;
struct omap_system_dma_plat_info *p;
struct resource *mem;
char *name = "omap_dma_system";
dma_stride = OMAP2_DMA_STRIDE;
dma_common_ch_start = CSDP;
p = kzalloc(sizeof(struct omap_system_dma_plat_info), GFP_KERNEL);
if (!p) {
pr_err("%s: Unable to allocate pdata for %s:%s\n",
__func__, name, oh->name);
return -ENOMEM;
}
p->dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr;
p->disable_irq_lch = omap2_disable_irq_lch;
p->show_dma_caps = omap2_show_dma_caps;
p->clear_dma = omap2_clear_dma;
p->dma_write = dma_write;
p->dma_read = dma_read;
p->clear_lch_regs = NULL;
p->errata = configure_dma_errata();
pdev = omap_device_build(name, 0, oh, p, sizeof(*p));
kfree(p);
if (IS_ERR(pdev)) {
pr_err("%s: Can't build omap_device for %s:%s.\n",
__func__, name, oh->name);
return PTR_ERR(pdev);
}
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
dev_err(&pdev->dev, "%s: no mem resource\n", __func__);
return -EINVAL;
}
dma_base = ioremap(mem->start, resource_size(mem));
if (!dma_base) {
dev_err(&pdev->dev, "%s: ioremap fail\n", __func__);
return -ENOMEM;
}
d = oh->dev_attr;
d->chan = kzalloc(sizeof(struct omap_dma_lch) *
(d->lch_count), GFP_KERNEL);
if (!d->chan) {
dev_err(&pdev->dev, "%s: kzalloc fail\n", __func__);
return -ENOMEM;
}
if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP))
d->dev_caps |= HS_CHANNELS_RESERVED;
/* Check the capabilities register for descriptor loading feature */
if (dma_read(CAPS_0, 0) & DMA_HAS_DESCRIPTOR_CAPS)
dma_common_ch_end = CCDN;
else
dma_common_ch_end = CCFN;
return 0;
}
static const struct platform_device_info omap_dma_dev_info = {
.name = "omap-dma-engine",
.id = -1,
.dma_mask = DMA_BIT_MASK(32),
};
static int __init omap2_system_dma_init(void)
{
struct platform_device *pdev;
int res;
res = omap_hwmod_for_each_by_class("dma",
omap2_system_dma_init_dev, NULL);
if (res)
return res;
if (of_have_populated_dt())
return res;
pdev = platform_device_register_full(&omap_dma_dev_info);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
return res;
}
omap_arch_initcall(omap2_system_dma_init);