[PATCH RFC 20/26] ARM: omap: clean up DMA register accesses

Russell King rmk+kernel at arm.linux.org.uk
Thu Jan 2 10:12:11 EST 2014


We can do much better with this by using a structure to describe each
register, rather than code.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
 arch/arm/mach-omap1/dma.c |  121 +++++++++++++++++++++------------------------
 arch/arm/mach-omap2/dma.c |   99 ++++++++++++++++++-------------------
 include/linux/omap-dma.h  |   13 +++++
 3 files changed, 117 insertions(+), 116 deletions(-)

diff --git a/arch/arm/mach-omap1/dma.c b/arch/arm/mach-omap1/dma.c
index 11f0b0ee67a3..de30e28ff487 100644
--- a/arch/arm/mach-omap1/dma.c
+++ b/arch/arm/mach-omap1/dma.c
@@ -32,53 +32,52 @@
 
 #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 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,
+static const struct omap_dma_reg reg_map[] = {
+	[GCR]		= { 0x0400, 0x00, OMAP_DMA_REG_16BIT },
+	[GSCR]		= { 0x0404, 0x00, OMAP_DMA_REG_16BIT },
+	[GRST1]		= { 0x0408, 0x00, OMAP_DMA_REG_16BIT },
+	[HW_ID]		= { 0x0442, 0x00, OMAP_DMA_REG_16BIT },
+	[PCH2_ID]	= { 0x0444, 0x00, OMAP_DMA_REG_16BIT },
+	[PCH0_ID]	= { 0x0446, 0x00, OMAP_DMA_REG_16BIT },
+	[PCH1_ID]	= { 0x0448, 0x00, OMAP_DMA_REG_16BIT },
+	[PCHG_ID]	= { 0x044a, 0x00, OMAP_DMA_REG_16BIT },
+	[PCHD_ID]	= { 0x044c, 0x00, OMAP_DMA_REG_16BIT },
+	[CAPS_0]	= { 0x044e, 0x00, OMAP_DMA_REG_2X16BIT },
+	[CAPS_1]	= { 0x0452, 0x00, OMAP_DMA_REG_2X16BIT },
+	[CAPS_2]	= { 0x0456, 0x00, OMAP_DMA_REG_16BIT },
+	[CAPS_3]	= { 0x0458, 0x00, OMAP_DMA_REG_16BIT },
+	[CAPS_4]	= { 0x045a, 0x00, OMAP_DMA_REG_16BIT },
+	[PCH2_SR]	= { 0x0460, 0x00, OMAP_DMA_REG_16BIT },
+	[PCH0_SR]	= { 0x0480, 0x00, OMAP_DMA_REG_16BIT },
+	[PCH1_SR]	= { 0x0482, 0x00, OMAP_DMA_REG_16BIT },
+	[PCHD_SR]	= { 0x04c0, 0x00, OMAP_DMA_REG_16BIT },
 
 	/* 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,
+	[CSDP]		= { 0x0000, 0x40, OMAP_DMA_REG_16BIT },
+	[CCR]		= { 0x0002, 0x40, OMAP_DMA_REG_16BIT },
+	[CICR]		= { 0x0004, 0x40, OMAP_DMA_REG_16BIT },
+	[CSR]		= { 0x0006, 0x40, OMAP_DMA_REG_16BIT },
+	[CEN]		= { 0x0010, 0x40, OMAP_DMA_REG_16BIT },
+	[CFN]		= { 0x0012, 0x40, OMAP_DMA_REG_16BIT },
+	[CSFI]		= { 0x0014, 0x40, OMAP_DMA_REG_16BIT },
+	[CSEI]		= { 0x0016, 0x40, OMAP_DMA_REG_16BIT },
+	[CPC]		= { 0x0018, 0x40, OMAP_DMA_REG_16BIT },	/* 15xx only */
+	[CSAC]		= { 0x0018, 0x40, OMAP_DMA_REG_16BIT },
+	[CDAC]		= { 0x001a, 0x40, OMAP_DMA_REG_16BIT },
+	[CDEI]		= { 0x001c, 0x40, OMAP_DMA_REG_16BIT },
+	[CDFI]		= { 0x001e, 0x40, OMAP_DMA_REG_16BIT },
+	[CLNK_CTRL]	= { 0x0028, 0x40, OMAP_DMA_REG_16BIT },
 
 	/* Channel specific register offsets */
-	[CSSA]		= 0x08,
-	[CDSA]		= 0x0c,
-	[COLOR]		= 0x20,
-	[CCR2]		= 0x24,
-	[LCH_CTRL]	= 0x2a,
+	[CSSA]		= { 0x0008, 0x40, OMAP_DMA_REG_2X16BIT },
+	[CDSA]		= { 0x000c, 0x40, OMAP_DMA_REG_2X16BIT },
+	[COLOR]		= { 0x0020, 0x40, OMAP_DMA_REG_2X16BIT },
+	[CCR2]		= { 0x0024, 0x40, OMAP_DMA_REG_16BIT },
+	[LCH_CTRL]	= { 0x002a, 0x40, OMAP_DMA_REG_16BIT },
 };
 
 static struct resource res[] __initdata = {
@@ -179,36 +178,28 @@ 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;
+	void __iomem *addr = dma_base;
 
-	stride = (reg >= CPC) ? OMAP1_DMA_STRIDE : 0;
-	offset = reg_map[reg] + (stride * lch);
+	addr += reg_map[reg].offset;
+	addr += 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);
-	}
+	__raw_writew(val, addr);
+	if (reg_map[reg].size == OMAP_DMA_REG_2X16BIT)
+		__raw_writew(val >> 16, addr + 2);
 }
 
 static inline u32 dma_read(int reg, int lch)
 {
-	u8 stride;
-	u32 offset, val;
-
-	stride = (reg >= CPC) ? OMAP1_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);
-	}
+	void __iomem *addr = dma_base;
+	uint32_t val;
+
+	addr += reg_map[reg].offset;
+	addr += reg_map[reg].stride * lch;
+
+	val = __raw_readw(addr);
+	if (reg_map[reg].size == OMAP_DMA_REG_2X16BIT)
+		val |= __raw_readw(addr + 2) << 16;
+
 	return val;
 }
 
diff --git a/arch/arm/mach-omap2/dma.c b/arch/arm/mach-omap2/dma.c
index e4ac7ac9a228..e633b48a3fcb 100644
--- a/arch/arm/mach-omap2/dma.c
+++ b/arch/arm/mach-omap2/dma.c
@@ -35,80 +35,77 @@
 #include "omap_hwmod.h"
 #include "omap_device.h"
 
-#define OMAP2_DMA_STRIDE	0x60
-
 static u32 errata;
 
 static struct omap_dma_dev_attr *d;
 
 static enum omap_reg_offsets 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,
+static const struct omap_dma_reg reg_map[] = {
+	[REVISION]	= { 0x0000, 0x00, OMAP_DMA_REG_32BIT },
+	[GCR]		= { 0x0078, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L0]	= { 0x0008, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L1]	= { 0x000c, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L2]	= { 0x0010, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQSTATUS_L3]	= { 0x0014, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L0]	= { 0x0018, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L1]	= { 0x001c, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L2]	= { 0x0020, 0x00, OMAP_DMA_REG_32BIT },
+	[IRQENABLE_L3]	= { 0x0024, 0x00, OMAP_DMA_REG_32BIT },
+	[SYSSTATUS]	= { 0x0028, 0x00, OMAP_DMA_REG_32BIT },
+	[OCP_SYSCONFIG]	= { 0x002c, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_0]	= { 0x0064, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_2]	= { 0x006c, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_3]	= { 0x0070, 0x00, OMAP_DMA_REG_32BIT },
+	[CAPS_4]	= { 0x0074, 0x00, OMAP_DMA_REG_32BIT },
 
 	/* 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,
+	[CCR]		= { 0x0080, 0x60, OMAP_DMA_REG_32BIT },
+	[CLNK_CTRL]	= { 0x0084, 0x60, OMAP_DMA_REG_32BIT },
+	[CICR]		= { 0x0088, 0x60, OMAP_DMA_REG_32BIT },
+	[CSR]		= { 0x008c, 0x60, OMAP_DMA_REG_32BIT },
+	[CSDP]		= { 0x0090, 0x60, OMAP_DMA_REG_32BIT },
+	[CEN]		= { 0x0094, 0x60, OMAP_DMA_REG_32BIT },
+	[CFN]		= { 0x0098, 0x60, OMAP_DMA_REG_32BIT },
+	[CSEI]		= { 0x00a4, 0x60, OMAP_DMA_REG_32BIT },
+	[CSFI]		= { 0x00a8, 0x60, OMAP_DMA_REG_32BIT },
+	[CDEI]		= { 0x00ac, 0x60, OMAP_DMA_REG_32BIT },
+	[CDFI]		= { 0x00b0, 0x60, OMAP_DMA_REG_32BIT },
+	[CSAC]		= { 0x00b4, 0x60, OMAP_DMA_REG_32BIT },
+	[CDAC]		= { 0x00b8, 0x60, OMAP_DMA_REG_32BIT },
 
 	/* Channel specific register offsets */
-	[CSSA]			= 0x9c,
-	[CDSA]			= 0xa0,
-	[CCEN]			= 0xbc,
-	[CCFN]			= 0xc0,
-	[COLOR]			= 0xc4,
+	[CSSA]		= { 0x009c, 0x60, OMAP_DMA_REG_32BIT },
+	[CDSA]		= { 0x00a0, 0x60, OMAP_DMA_REG_32BIT },
+	[CCEN]		= { 0x00bc, 0x60, OMAP_DMA_REG_32BIT },
+	[CCFN]		= { 0x00c0, 0x60, OMAP_DMA_REG_32BIT },
+	[COLOR]		= { 0x00c4, 0x60, OMAP_DMA_REG_32BIT },
 
 	/* OMAP4 specific registers */
-	[CDP]			= 0xd0,
-	[CNDP]			= 0xd4,
-	[CCDN]			= 0xd8,
+	[CDP]		= { 0x00d0, 0x60, OMAP_DMA_REG_32BIT },
+	[CNDP]		= { 0x00d4, 0x60, OMAP_DMA_REG_32BIT },
+	[CCDN]		= { 0x00d8, 0x60, OMAP_DMA_REG_32BIT },
 };
 
 static void __iomem *dma_base;
 static inline void dma_write(u32 val, int reg, int lch)
 {
-	u8  stride;
-	u32 offset;
+	void __iomem *addr = dma_base;
+
+	addr += reg_map[reg].offset;
+	addr += reg_map[reg].stride * lch;
 
-	stride = (reg >= CSDP) ? OMAP2_DMA_STRIDE : 0;
-	offset = reg_map[reg] + (stride * lch);
-	__raw_writel(val, dma_base + offset);
+	__raw_writel(val, addr);
 }
 
 static inline u32 dma_read(int reg, int lch)
 {
-	u8 stride;
-	u32 offset, val;
+	void __iomem *addr = dma_base;
+
+	addr += reg_map[reg].offset;
+	addr += reg_map[reg].stride * lch;
 
-	stride = (reg >= CSDP) ? OMAP2_DMA_STRIDE : 0;
-	offset = reg_map[reg] + (stride * lch);
-	val = __raw_readl(dma_base + offset);
-	return val;
+	return __raw_readl(addr);
 }
 
 static void omap2_clear_dma(int lch)
diff --git a/include/linux/omap-dma.h b/include/linux/omap-dma.h
index 0bb7de77d478..41328725721a 100644
--- a/include/linux/omap-dma.h
+++ b/include/linux/omap-dma.h
@@ -271,6 +271,19 @@ struct omap_dma_dev_attr {
 	struct omap_dma_lch *chan;
 };
 
+enum {
+	OMAP_DMA_REG_NONE,
+	OMAP_DMA_REG_16BIT,
+	OMAP_DMA_REG_2X16BIT,
+	OMAP_DMA_REG_32BIT,
+};
+
+struct omap_dma_reg {
+	u16	offset;
+	u8	stride;
+	u8	type;
+};
+
 /* System DMA platform data structure */
 struct omap_system_dma_plat_info {
 	struct omap_dma_dev_attr *dma_attr;
-- 
1.7.4.4




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