OMAP: DMA: Convert DMA library into platform driver

Convert DMA library into DMA platform driver and make use of
platform data provided by hwmod data base for OMAP2+ onwards.

For OMAP1 processors, the DMA driver in mach-omap uses resource
structures for getting platform data.

Thanks to Tony Lindgren <tony@atomide.com> for fixing various
omap1 issues and testing the same on OSK5912 board.
Signed-off-by: G, Manjunath Kondaiah <manjugk@ti.com>
Tested-by: Kevin Hilman <khilman@deeprootsystems.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap1/Makefile

@@ -3,7 +3,7 @@
 #
 
 # Common support
-obj-y := io.o id.o sram.o irq.o mux.o flash.o serial.o devices.o
+obj-y := io.o id.o sram.o irq.o mux.o flash.o serial.o devices.o dma.o
 obj-y += clock.o clock_data.o opp_data.o
 
 obj-$(CONFIG_OMAP_MCBSP) += mcbsp.o

arch/arm/mach-omap1/dma.c

@@ -30,6 +30,57 @@
 #include <plat/irqs.h>
 
 #define OMAP1_DMA_BASE			(0xfffed800)
+#define OMAP1_LOGICAL_DMA_CH_COUNT	17
+#define OMAP1_DMA_STRIDE		0x40
+
+static u32 errata;
+static u32 enable_1510_mode;
+static u8 dma_stride;
+static enum omap_reg_offsets dma_common_ch_start, dma_common_ch_end;
+
+static u16 reg_map[] = {
+	[GCR]		= 0x400,
+	[GSCR]		= 0x404,
+	[GRST1]		= 0x408,
+	[HW_ID]		= 0x442,
+	[PCH2_ID]	= 0x444,
+	[PCH0_ID]	= 0x446,
+	[PCH1_ID]	= 0x448,
+	[PCHG_ID]	= 0x44a,
+	[PCHD_ID]	= 0x44c,
+	[CAPS_0]	= 0x44e,
+	[CAPS_1]	= 0x452,
+	[CAPS_2]	= 0x456,
+	[CAPS_3]	= 0x458,
+	[CAPS_4]	= 0x45a,
+	[PCH2_SR]	= 0x460,
+	[PCH0_SR]	= 0x480,
+	[PCH1_SR]	= 0x482,
+	[PCHD_SR]	= 0x4c0,
+
+	/* Common Registers */
+	[CSDP]		= 0x00,
+	[CCR]		= 0x02,
+	[CICR]		= 0x04,
+	[CSR]		= 0x06,
+	[CEN]		= 0x10,
+	[CFN]		= 0x12,
+	[CSFI]		= 0x14,
+	[CSEI]		= 0x16,
+	[CPC]		= 0x18,	/* 15xx only */
+	[CSAC]		= 0x18,
+	[CDAC]		= 0x1a,
+	[CDEI]		= 0x1c,
+	[CDFI]		= 0x1e,
+	[CLNK_CTRL]	= 0x28,
+
+	/* Channel specific register offsets */
+	[CSSA]		= 0x08,
+	[CDSA]		= 0x0c,
+	[COLOR]		= 0x20,
+	[CCR2]		= 0x24,
+	[LCH_CTRL]	= 0x2a,
+};
 
 static struct resource res[] __initdata = {
 	[0] = {
@@ -67,6 +118,7 @@ static struct resource res[] __initdata = {
 		.start  = INT_DMA_CH5,
 		.flags  = IORESOURCE_IRQ,
 	},
+	/* Handled in lcd_dma.c */
 	[7] = {
 		.name   = "6",
 		.start  = INT_1610_DMA_CH6,
@@ -125,9 +177,100 @@ static struct resource res[] __initdata = {
 	},
 };
 
+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_writew(val, dma_base + offset);
+	if ((reg > CLNK_CTRL && reg < CCEN) ||
+			(reg > PCHD_ID && reg < CAPS_2)) {
+		u32 offset2 = reg_map[reg] + 2 + (stride * lch);
+		__raw_writew(val >> 16, dma_base + offset2);
+	}
+}
+
+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_readw(dma_base + offset);
+	if ((reg > CLNK_CTRL && reg < CCEN) ||
+			(reg > PCHD_ID && reg < CAPS_2)) {
+		u16 upper;
+		u32 offset2 = reg_map[reg] + 2 + (stride * lch);
+		upper = __raw_readw(dma_base + offset2);
+		val |= (upper << 16);
+	}
+	return val;
+}
+
+static void omap1_clear_lch_regs(int lch)
+{
+	int i = dma_common_ch_start;
+
+	for (; i <= dma_common_ch_end; i += 1)
+		dma_write(0, i, lch);
+}
+
+static void omap1_clear_dma(int lch)
+{
+	u32 l;
+
+	l = dma_read(CCR, lch);
+	l &= ~OMAP_DMA_CCR_EN;
+	dma_write(l, CCR, lch);
+
+	/* Clear pending interrupts */
+	l = dma_read(CSR, lch);
+}
+
+static void omap1_show_dma_caps(void)
+{
+	if (enable_1510_mode) {
+		printk(KERN_INFO "DMA support for OMAP15xx initialized\n");
+	} else {
+		u16 w;
+		printk(KERN_INFO "OMAP DMA hardware version %d\n",
+							dma_read(HW_ID, 0));
+		printk(KERN_INFO "DMA capabilities: %08x:%08x:%04x:%04x:%04x\n",
+			dma_read(CAPS_0, 0), dma_read(CAPS_1, 0),
+			dma_read(CAPS_2, 0), dma_read(CAPS_3, 0),
+			dma_read(CAPS_4, 0));
+
+		/* Disable OMAP 3.0/3.1 compatibility mode. */
+		w = dma_read(GSCR, 0);
+		w |= 1 << 3;
+		dma_write(w, GSCR, 0);
+	}
+	return;
+}
+
+static u32 configure_dma_errata(void)
+{
+
+	/*
+	 * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is
+	 * read before the DMA controller finished disabling the channel.
+	 */
+	if (!cpu_is_omap15xx())
+		SET_DMA_ERRATA(DMA_ERRATA_3_3);
+
+	return errata;
+}
+
 static int __init omap1_system_dma_init(void)
 {
 	struct omap_system_dma_plat_info	*p;
+	struct omap_dma_dev_attr		*d;
 	struct platform_device			*pdev;
 	int ret;
 
@@ -138,6 +281,12 @@ static int __init omap1_system_dma_init(void)
 		return -ENOMEM;
 	}
 
+	dma_base = ioremap(res[0].start, resource_size(&res[0]));
+	if (!dma_base) {
+		pr_err("%s: Unable to ioremap\n", __func__);
+		return -ENODEV;
+	}
+
 	ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
 	if (ret) {
 		dev_err(&pdev->dev, "%s: Unable to add resources for %s%d\n",
@@ -153,22 +302,84 @@ static int __init omap1_system_dma_init(void)
 		goto exit_device_put;
 	}
 
+	d = kzalloc(sizeof(struct omap_dma_dev_attr), GFP_KERNEL);
+	if (!d) {
+		dev_err(&pdev->dev, "%s: Unable to allocate 'd' for %s\n",
+			__func__, pdev->name);
+		ret = -ENOMEM;
+		goto exit_release_p;
+	}
+
+	d->lch_count		= OMAP1_LOGICAL_DMA_CH_COUNT;
+
+	/* Valid attributes for omap1 plus processors */
+	if (cpu_is_omap15xx())
+		d->dev_caps = ENABLE_1510_MODE;
+	enable_1510_mode = d->dev_caps & ENABLE_1510_MODE;
+
+	d->dev_caps		|= SRC_PORT;
+	d->dev_caps		|= DST_PORT;
+	d->dev_caps		|= SRC_INDEX;
+	d->dev_caps		|= DST_INDEX;
+	d->dev_caps		|= IS_BURST_ONLY4;
+	d->dev_caps		|= CLEAR_CSR_ON_READ;
+	d->dev_caps		|= IS_WORD_16;
+
+
+	d->chan = kzalloc(sizeof(struct omap_dma_lch) *
+					(d->lch_count), GFP_KERNEL);
+	if (!d->chan) {
+		dev_err(&pdev->dev, "%s: Memory allocation failed"
+					"for d->chan!!!\n", __func__);
+		goto exit_release_d;
+	}
+
+	if (cpu_is_omap15xx())
+		d->chan_count = 9;
+	else if (cpu_is_omap16xx() || cpu_is_omap7xx()) {
+		if (!(d->dev_caps & ENABLE_1510_MODE))
+			d->chan_count = 16;
+		else
+			d->chan_count = 9;
+	}
+
+	p->dma_attr = d;
+
+	p->show_dma_caps	= omap1_show_dma_caps;
+	p->clear_lch_regs	= omap1_clear_lch_regs;
+	p->clear_dma		= omap1_clear_dma;
+	p->dma_write		= dma_write;
+	p->dma_read		= dma_read;
+	p->disable_irq_lch	= NULL;
+
+	p->errata = configure_dma_errata();
+
 	ret = platform_device_add_data(pdev, p, sizeof(*p));
 	if (ret) {
 		dev_err(&pdev->dev, "%s: Unable to add resources for %s%d\n",
 			__func__, pdev->name, pdev->id);
-		goto exit_device_put;
+		goto exit_release_chan;
 	}
 
 	ret = platform_device_add(pdev);
 	if (ret) {
 		dev_err(&pdev->dev, "%s: Unable to add resources for %s%d\n",
 			__func__, pdev->name, pdev->id);
-		goto exit_device_put;
+		goto exit_release_chan;
 	}
 
+	dma_stride		= OMAP1_DMA_STRIDE;
+	dma_common_ch_start	= CPC;
+	dma_common_ch_end	= COLOR;
+
 	return ret;
 
+exit_release_chan:
+	kfree(d->chan);
+exit_release_d:
+	kfree(d);
+exit_release_p:
+	kfree(p);
 exit_device_put:
 	platform_device_put(pdev);
 exit_device_del:

arch/arm/mach-omap2/Makefile

@@ -4,7 +4,7 @@
 
 # Common support
 obj-y := id.o io.o control.o mux.o devices.o serial.o gpmc.o timer-gp.o pm.o \
-	 common.o gpio.o
+	 common.o gpio.o dma.o
 
 omap-2-3-common				= irq.o sdrc.o prm2xxx_3xxx.o
 hwmod-common				= omap_hwmod.o \

arch/arm/mach-omap2/dma.c

@@ -32,6 +32,61 @@
 #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,
@@ -40,13 +95,151 @@ static struct omap_device_pm_latency omap2_dma_latency[] = {
 	},
 };
 
+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",
@@ -54,6 +247,17 @@ static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
 		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);
@@ -63,6 +267,25 @@ static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused)
 		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;
 }
 

arch/arm/plat-omap/include/plat/dma.h

@@ -21,19 +21,15 @@
 #ifndef __ASM_ARCH_DMA_H
 #define __ASM_ARCH_DMA_H
 
-/* Move omap4 specific defines to dma-44xx.h */
-#include "dma-44xx.h"
-
-/* Hardware registers for omap1 */
-#define OMAP1_DMA_BASE			(0xfffed800)
+#include <linux/platform_device.h>
 
-/* Hardware registers for omap2 and omap3 */
-#define OMAP24XX_DMA4_BASE		(L4_24XX_BASE + 0x56000)
-#define OMAP34XX_DMA4_BASE		(L4_34XX_BASE + 0x56000)
-#define OMAP44XX_DMA4_BASE		(L4_44XX_BASE + 0x56000)
+/*
+ * TODO: These dma channel defines should go away once all
+ * the omap drivers hwmod adapted.
+ */
 
-#define OMAP1_LOGICAL_DMA_CH_COUNT	17
-#define OMAP_DMA4_LOGICAL_DMA_CH_COUNT	32	/* REVISIT: Is this 32 + 2? */
+/* Move omap4 specific defines to dma-44xx.h */
+#include "dma-44xx.h"
 
 /* DMA channels for omap1 */
 #define OMAP_DMA_NO_DEVICE		0
@@ -302,6 +298,14 @@
 #define IS_CSSA_32			BIT(0x3)
 #define IS_CDSA_32			BIT(0x4)
 #define IS_RW_PRIORITY			BIT(0x5)
+#define ENABLE_1510_MODE		BIT(0x6)
+#define SRC_PORT			BIT(0x7)
+#define DST_PORT			BIT(0x8)
+#define SRC_INDEX			BIT(0x9)
+#define DST_INDEX			BIT(0xA)
+#define IS_BURST_ONLY4			BIT(0xB)
+#define CLEAR_CSR_ON_READ		BIT(0xC)
+#define IS_WORD_16			BIT(0xD)
 
 enum omap_reg_offsets {
 
@@ -397,9 +401,40 @@ struct omap_dma_channel_params {
 #endif
 };
 
+struct omap_dma_lch {
+	int next_lch;
+	int dev_id;
+	u16 saved_csr;
+	u16 enabled_irqs;
+	const char *dev_name;
+	void (*callback)(int lch, u16 ch_status, void *data);
+	void *data;
+	long flags;
+	/* required for Dynamic chaining */
+	int prev_linked_ch;
+	int next_linked_ch;
+	int state;
+	int chain_id;
+	int status;
+};
+
 struct omap_dma_dev_attr {
 	u32 dev_caps;
 	u16 lch_count;
+	u16 chan_count;
+	struct omap_dma_lch *chan;
+};
+
+/* System DMA platform data structure */
+struct omap_system_dma_plat_info {
+	struct omap_dma_dev_attr *dma_attr;
+	u32 errata;
+	void (*disable_irq_lch)(int lch);
+	void (*show_dma_caps)(void);
+	void (*clear_lch_regs)(int lch);
+	void (*clear_dma)(int lch);
+	void (*dma_write)(u32 val, int reg, int lch);
+	u32 (*dma_read)(int reg, int lch);
 };
 
 extern void omap_set_dma_priority(int lch, int dst_port, int priority);