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Diffstat (limited to 'arch/arm/mach-omap2/dma.c')
-rw-r--r--arch/arm/mach-omap2/dma.c297
1 files changed, 297 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/dma.c b/arch/arm/mach-omap2/dma.c
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index 00000000000..d2f15f5cfd3
--- /dev/null
+++ b/arch/arm/mach-omap2/dma.c
@@ -0,0 +1,297 @@
+/*
+ * 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 struct omap_device_pm_latency omap2_dma_latency[] = {
+ {
+ .deactivate_func = omap_device_idle_hwmods,
+ .activate_func = omap_device_enable_hwmods,
+ .flags = OMAP_DEVICE_LATENCY_AUTO_ADJUST,
+ },
+};
+
+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 omap_device *od;
+ 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_omap4430())
+ 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();
+
+ od = omap_device_build(name, 0, oh, p, sizeof(*p),
+ omap2_dma_latency, ARRAY_SIZE(omap2_dma_latency), 0);
+ kfree(p);
+ if (IS_ERR(od)) {
+ pr_err("%s: Cant build omap_device for %s:%s.\n",
+ __func__, name, oh->name);
+ return IS_ERR(od);
+ }
+
+ mem = platform_get_resource(&od->pdev, IORESOURCE_MEM, 0);
+ if (!mem) {
+ dev_err(&od->pdev.dev, "%s: no mem resource\n", __func__);
+ return -EINVAL;
+ }
+ dma_base = ioremap(mem->start, resource_size(mem));
+ if (!dma_base) {
+ dev_err(&od->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(&od->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);