/*
* 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 <plat/omap_hwmod.h>
#include <plat/omap_device.h>
#include <plat/dma.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;
if (cpu_is_omap3630() || cpu_is_omap44xx())
dma_common_ch_end = CCDN;
else
dma_common_ch_end = CCFN;
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), NULL, 0, 0);
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;
}
return 0;
}
static int __init omap2_system_dma_init(void)
{
return omap_hwmod_for_each_by_class("dma",
omap2_system_dma_init_dev, NULL);
}
arch_initcall(omap2_system_dma_init);