sh: dma: More legacy cpu dma chainsawing.

Attempt to "tidy" up some of the multi IRQ handling and base + IRQ
management. This should keep it limping along without too much hassle,
and no new parts should ever be enabling or using this API anyways.

It doesn't get any closer to lipstick on a pig as this.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

arch/sh/drivers/dma/dma-sh.c

@@ -14,35 +14,72 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/module.h>
+#include <linux/io.h>
 #include <mach-dreamcast/mach/dma.h>
 #include <asm/dma.h>
-#include <asm/io.h>
-#include <asm/dma-sh.h>
+#include <asm/dma-register.h>
+#include <cpu/dma-register.h>
+#include <cpu/dma.h>
 
-#if defined(DMAE1_IRQ)
-#define NR_DMAE		2
-#else
-#define NR_DMAE		1
+/*
+ * Define the default configuration for dual address memory-memory transfer.
+ * The 0x400 value represents auto-request, external->external.
+ */
+#define RS_DUAL	(DM_INC | SM_INC | 0x400 | TS_INDEX2VAL(XMIT_SZ_32BIT))
+
+static unsigned long dma_find_base(unsigned int chan)
+{
+	unsigned long base = SH_DMAC_BASE0;
+
+#ifdef SH_DMAC_BASE1
+	if (chan >= 6)
+		base = SH_DMAC_BASE1;
 #endif
 
-static const char *dmae_name[] = {
-	"DMAC Address Error0", "DMAC Address Error1"
-};
+	return base;
+}
+
+static unsigned long dma_base_addr(unsigned int chan)
+{
+	unsigned long base = dma_find_base(chan);
+
+	/* Normalize offset calculation */
+	if (chan >= 9)
+		chan -= 6;
+	if (chan >= 4)
+		base += 0x10;
+
+	return base + (chan * 0x10);
+}
 
+#ifdef CONFIG_SH_DMA_IRQ_MULTI
 static inline unsigned int get_dmte_irq(unsigned int chan)
 {
-	unsigned int irq = 0;
-	if (chan < ARRAY_SIZE(dmte_irq_map))
-		irq = dmte_irq_map[chan];
-
-#if defined(CONFIG_SH_DMA_IRQ_MULTI)
-	if (irq > DMTE6_IRQ)
-		return DMTE6_IRQ;
-	return DMTE0_IRQ;
+	return chan >= 6 ? DMTE6_IRQ : DMTE0_IRQ;
+}
 #else
-	return irq;
+
+static unsigned int dmte_irq_map[] = {
+	DMTE0_IRQ, DMTE0_IRQ + 1, DMTE0_IRQ + 2, DMTE0_IRQ + 3,
+
+#ifdef DMTE4_IRQ
+	DMTE4_IRQ, DMTE4_IRQ + 1,
+#endif
+
+#ifdef DMTE6_IRQ
+	DMTE6_IRQ, DMTE6_IRQ + 1,
+#endif
+
+#ifdef DMTE8_IRQ
+	DMTE8_IRQ, DMTE9_IRQ, DMTE10_IRQ, DMTE11_IRQ,
 #endif
+};
+
+static inline unsigned int get_dmte_irq(unsigned int chan)
+{
+	return dmte_irq_map[chan];
 }
+#endif
 
 /*
  * We determine the correct shift size based off of the CHCR transmit size
@@ -53,9 +90,10 @@ static inline unsigned int get_dmte_irq(unsigned int chan)
  * iterations to complete the transfer.
  */
 static unsigned int ts_shift[] = TS_SHIFT;
+
 static inline unsigned int calc_xmit_shift(struct dma_channel *chan)
 {
-	u32 chcr = __raw_readl(dma_base_addr[chan->chan] + CHCR);
+	u32 chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR);
 	int cnt = ((chcr & CHCR_TS_LOW_MASK) >> CHCR_TS_LOW_SHIFT) |
 		((chcr & CHCR_TS_HIGH_MASK) >> CHCR_TS_HIGH_SHIFT);
 
@@ -73,13 +111,13 @@ static irqreturn_t dma_tei(int irq, void *dev_id)
 	struct dma_channel *chan = dev_id;
 	u32 chcr;
 
-	chcr = __raw_readl(dma_base_addr[chan->chan] + CHCR);
+	chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR);
 
 	if (!(chcr & CHCR_TE))
 		return IRQ_NONE;
 
 	chcr &= ~(CHCR_IE | CHCR_DE);
-	__raw_writel(chcr, (dma_base_addr[chan->chan] + CHCR));
+	__raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR));
 
 	wake_up(&chan->wait_queue);
 
@@ -91,13 +129,8 @@ static int sh_dmac_request_dma(struct dma_channel *chan)
 	if (unlikely(!(chan->flags & DMA_TEI_CAPABLE)))
 		return 0;
 
-	return request_irq(get_dmte_irq(chan->chan), dma_tei,
-#if defined(CONFIG_SH_DMA_IRQ_MULTI)
-				IRQF_SHARED,
-#else
-				0,
-#endif
-				chan->dev_id, chan);
+	return request_irq(get_dmte_irq(chan->chan), dma_tei, IRQF_SHARED,
+			   chan->dev_id, chan);
 }
 
 static void sh_dmac_free_dma(struct dma_channel *chan)
@@ -118,7 +151,7 @@ sh_dmac_configure_channel(struct dma_channel *chan, unsigned long chcr)
 		chan->flags &= ~DMA_TEI_CAPABLE;
 	}
 
-	__raw_writel(chcr, (dma_base_addr[chan->chan] + CHCR));
+	__raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR));
 
 	chan->flags |= DMA_CONFIGURED;
 	return 0;
@@ -129,13 +162,13 @@ static void sh_dmac_enable_dma(struct dma_channel *chan)
 	int irq;
 	u32 chcr;
 
-	chcr = __raw_readl(dma_base_addr[chan->chan] + CHCR);
+	chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR);
 	chcr |= CHCR_DE;
 
 	if (chan->flags & DMA_TEI_CAPABLE)
 		chcr |= CHCR_IE;
 
-	__raw_writel(chcr, (dma_base_addr[chan->chan] + CHCR));
+	__raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR));
 
 	if (chan->flags & DMA_TEI_CAPABLE) {
 		irq = get_dmte_irq(chan->chan);
@@ -153,9 +186,9 @@ static void sh_dmac_disable_dma(struct dma_channel *chan)
 		disable_irq(irq);
 	}
 
-	chcr = __raw_readl(dma_base_addr[chan->chan] + CHCR);
+	chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR);
 	chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE);
-	__raw_writel(chcr, (dma_base_addr[chan->chan] + CHCR));
+	__raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR));
 }
 
 static int sh_dmac_xfer_dma(struct dma_channel *chan)
@@ -186,13 +219,13 @@ static int sh_dmac_xfer_dma(struct dma_channel *chan)
 	 */
 	if (chan->sar || (mach_is_dreamcast() &&
 			  chan->chan == PVR2_CASCADE_CHAN))
-		__raw_writel(chan->sar, (dma_base_addr[chan->chan]+SAR));
+		__raw_writel(chan->sar, (dma_base_addr(chan->chan) + SAR));
 	if (chan->dar || (mach_is_dreamcast() &&
 			  chan->chan == PVR2_CASCADE_CHAN))
-		__raw_writel(chan->dar, (dma_base_addr[chan->chan] + DAR));
+		__raw_writel(chan->dar, (dma_base_addr(chan->chan) + DAR));
 
 	__raw_writel(chan->count >> calc_xmit_shift(chan),
-		(dma_base_addr[chan->chan] + TCR));
+		(dma_base_addr(chan->chan) + TCR));
 
 	sh_dmac_enable_dma(chan);
 
@@ -201,13 +234,32 @@ static int sh_dmac_xfer_dma(struct dma_channel *chan)
 
 static int sh_dmac_get_dma_residue(struct dma_channel *chan)
 {
-	if (!(__raw_readl(dma_base_addr[chan->chan] + CHCR) & CHCR_DE))
+	if (!(__raw_readl(dma_base_addr(chan->chan) + CHCR) & CHCR_DE))
 		return 0;
 
-	return __raw_readl(dma_base_addr[chan->chan] + TCR)
+	return __raw_readl(dma_base_addr(chan->chan) + TCR)
 		 << calc_xmit_shift(chan);
 }
 
+/*
+ * DMAOR handling
+ */
+#if defined(CONFIG_CPU_SUBTYPE_SH7723)	|| \
+    defined(CONFIG_CPU_SUBTYPE_SH7724)	|| \
+    defined(CONFIG_CPU_SUBTYPE_SH7780)	|| \
+    defined(CONFIG_CPU_SUBTYPE_SH7785)
+#define NR_DMAOR	2
+#else
+#define NR_DMAOR	1
+#endif
+
+/*
+ * DMAOR bases are broken out amongst channel groups. DMAOR0 manages
+ * channels 0 - 5, DMAOR1 6 - 11 (optional).
+ */
+#define dmaor_read_reg(n)		__raw_readw(dma_find_base((n)*6))
+#define dmaor_write_reg(n, data)	__raw_writew(data, dma_find_base(n)*6)
+
 static inline int dmaor_reset(int no)
 {
 	unsigned long dmaor = dmaor_read_reg(no);
@@ -228,36 +280,86 @@ static inline int dmaor_reset(int no)
 	return 0;
 }
 
-#if defined(CONFIG_CPU_SH4)
-static irqreturn_t dma_err(int irq, void *dummy)
-{
-#if defined(CONFIG_SH_DMA_IRQ_MULTI)
-	int cnt = 0;
-	switch (irq) {
-#if defined(DMTE6_IRQ) && defined(DMAE1_IRQ)
-	case DMTE6_IRQ:
-		cnt++;
+/*
+ * DMAE handling
+ */
+#ifdef CONFIG_CPU_SH4
+
+#if defined(DMAE1_IRQ)
+#define NR_DMAE		2
+#else
+#define NR_DMAE		1
 #endif
-	case DMTE0_IRQ:
-		if (dmaor_read_reg(cnt) & (DMAOR_NMIF | DMAOR_AE)) {
-			disable_irq(irq);
-			/* DMA multi and error IRQ */
-			return IRQ_HANDLED;
-		}
-	default:
-		return IRQ_NONE;
-	}
+
+static const char *dmae_name[] = {
+	"DMAC Address Error0",
+	"DMAC Address Error1"
+};
+
+#ifdef CONFIG_SH_DMA_IRQ_MULTI
+static inline unsigned int get_dma_error_irq(int n)
+{
+	return get_dmte_irq(n * 6);
+}
 #else
-	dmaor_reset(0);
-#if defined(CONFIG_CPU_SUBTYPE_SH7723)	|| \
-		defined(CONFIG_CPU_SUBTYPE_SH7780)	|| \
-		defined(CONFIG_CPU_SUBTYPE_SH7785)
-	dmaor_reset(1);
+
+static unsigned int dmae_irq_map[] = {
+	DMAE0_IRQ,
+
+#ifdef DMAE1_IRQ
+	DMAE1_IRQ,
+#endif
+};
+
+static inline unsigned int get_dma_error_irq(int n)
+{
+	return dmae_irq_map[n];
+}
 #endif
+
+static irqreturn_t dma_err(int irq, void *dummy)
+{
+	int i;
+
+	for (i = 0; i < NR_DMAOR; i++)
+		dmaor_reset(i);
+
 	disable_irq(irq);
 
 	return IRQ_HANDLED;
-#endif
+}
+
+static int dmae_irq_init(void)
+{
+	int n;
+
+	for (n = 0; n < NR_DMAE; n++) {
+		int i = request_irq(get_dma_error_irq(n), dma_err,
+				    IRQF_SHARED, dmae_name[n], NULL);
+		if (unlikely(i < 0)) {
+			printk(KERN_ERR "%s request_irq fail\n", dmae_name[n]);
+			return i;
+		}
+	}
+
+	return 0;
+}
+
+static void dmae_irq_free(void)
+{
+	int n;
+
+	for (n = 0; n < NR_DMAE; n++)
+		free_irq(get_dma_error_irq(n), NULL);
+}
+#else
+static inline int dmae_irq_init(void)
+{
+	return 0;
+}
+
+static void dmae_irq_free(void)
+{
 }
 #endif
 
@@ -276,72 +378,34 @@ static struct dma_info sh_dmac_info = {
 	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
 };
 
-#ifdef CONFIG_CPU_SH4
-static unsigned int get_dma_error_irq(int n)
-{
-#if defined(CONFIG_SH_DMA_IRQ_MULTI)
-	return (n == 0) ? get_dmte_irq(0) : get_dmte_irq(6);
-#else
-	return (n == 0) ? DMAE0_IRQ :
-#if defined(DMAE1_IRQ)
-				DMAE1_IRQ;
-#else
-				-1;
-#endif
-#endif
-}
-#endif
-
 static int __init sh_dmac_init(void)
 {
 	struct dma_info *info = &sh_dmac_info;
-	int i;
-
-#ifdef CONFIG_CPU_SH4
-	int n;
+	int i, rc;
 
-	for (n = 0; n < NR_DMAE; n++) {
-		i = request_irq(get_dma_error_irq(n), dma_err,
-#if defined(CONFIG_SH_DMA_IRQ_MULTI)
-				IRQF_SHARED,
-#else
-				0,
-#endif
-				dmae_name[n], (void *)dmae_name[n]);
-		if (unlikely(i < 0)) {
-			printk(KERN_ERR "%s request_irq fail\n", dmae_name[n]);
-			return i;
-		}
-	}
-#endif /* CONFIG_CPU_SH4 */
+	/*
+	 * Initialize DMAE, for parts that support it.
+	 */
+	rc = dmae_irq_init();
+	if (unlikely(rc != 0))
+		return rc;
 
 	/*
 	 * Initialize DMAOR, and clean up any error flags that may have
 	 * been set.
 	 */
-	i = dmaor_reset(0);
-	if (unlikely(i != 0))
-		return i;
-#if defined(CONFIG_CPU_SUBTYPE_SH7723)	|| \
-		defined(CONFIG_CPU_SUBTYPE_SH7780)	|| \
-		defined(CONFIG_CPU_SUBTYPE_SH7785)
-	i = dmaor_reset(1);
-	if (unlikely(i != 0))
-		return i;
-#endif
+	for (i = 0; i < NR_DMAOR; i++) {
+		rc = dmaor_reset(i);
+		if (unlikely(rc != 0))
+			return rc;
+	}
 
 	return register_dmac(info);
 }
 
 static void __exit sh_dmac_exit(void)
 {
-#ifdef CONFIG_CPU_SH4
-	int n;
-
-	for (n = 0; n < NR_DMAE; n++) {
-		free_irq(get_dma_error_irq(n), (void *)dmae_name[n]);
-	}
-#endif /* CONFIG_CPU_SH4 */
+	dmae_irq_free();
 	unregister_dmac(&sh_dmac_info);
 }
 

arch/sh/include/asm/dma-sh.h

-/*
- * arch/sh/include/asm/dma-sh.h
- *
- * Copyright (C) 2000  Takashi YOSHII
- * Copyright (C) 2003  Paul Mundt
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file "COPYING" in the main directory of this archive
- * for more details.
- */
-#ifndef __DMA_SH_H
-#define __DMA_SH_H
-
-#include <asm/dma-register.h>
-#include <cpu/dma-register.h>
-#include <cpu/dma.h>
-
-/* DMAOR contorl: The DMAOR access size is different by CPU.*/
-#if defined(CONFIG_CPU_SUBTYPE_SH7723)	|| \
-    defined(CONFIG_CPU_SUBTYPE_SH7724)	|| \
-    defined(CONFIG_CPU_SUBTYPE_SH7780)	|| \
-    defined(CONFIG_CPU_SUBTYPE_SH7785)
-#define dmaor_read_reg(n) \
-    (n ? __raw_readw(SH_DMAC_BASE1 + DMAOR) \
-	: __raw_readw(SH_DMAC_BASE0 + DMAOR))
-#define dmaor_write_reg(n, data) \
-    (n ? __raw_writew(data, SH_DMAC_BASE1 + DMAOR) \
-    : __raw_writew(data, SH_DMAC_BASE0 + DMAOR))
-#else /* Other CPU */
-#define dmaor_read_reg(n) __raw_readw(SH_DMAC_BASE0 + DMAOR)
-#define dmaor_write_reg(n, data) __raw_writew(data, SH_DMAC_BASE0 + DMAOR)
-#endif
-
-static int dmte_irq_map[] __maybe_unused = {
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 4)
-    DMTE0_IRQ,
-    DMTE0_IRQ + 1,
-    DMTE0_IRQ + 2,
-    DMTE0_IRQ + 3,
-#endif
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 6)
-    DMTE4_IRQ,
-    DMTE4_IRQ + 1,
-#endif
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 8)
-    DMTE6_IRQ,
-    DMTE6_IRQ + 1,
-#endif
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 12)
-    DMTE8_IRQ,
-    DMTE9_IRQ,
-    DMTE10_IRQ,
-    DMTE11_IRQ,
-#endif
-};
-
-/*
- * Define the default configuration for dual address memory-memory transfer.
- * The 0x400 value represents auto-request, external->external.
- */
-#define RS_DUAL	(DM_INC | SM_INC | 0x400 | TS_INDEX2VAL(XMIT_SZ_32BIT))
-
-/* DMA base address */
-static u32 dma_base_addr[] __maybe_unused = {
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 4)
-	SH_DMAC_BASE0 + 0x00,	/* channel 0 */
-	SH_DMAC_BASE0 + 0x10,
-	SH_DMAC_BASE0 + 0x20,
-	SH_DMAC_BASE0 + 0x30,
-#endif
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 6)
-	SH_DMAC_BASE0 + 0x50,
-	SH_DMAC_BASE0 + 0x60,
-#endif
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 8)
-	SH_DMAC_BASE1 + 0x00,
-	SH_DMAC_BASE1 + 0x10,
-#endif
-#if (CONFIG_NR_ONCHIP_DMA_CHANNELS >= 12)
-	SH_DMAC_BASE1 + 0x20,
-	SH_DMAC_BASE1 + 0x30,
-	SH_DMAC_BASE1 + 0x50,
-	SH_DMAC_BASE1 + 0x60, /* channel 11 */
-#endif
-};
-
-#endif /* __DMA_SH_H */

arch/sh/include/cpu-sh4a/cpu/dma.h

@@ -9,20 +9,17 @@
 #define DMTE4_IRQ	evt2irq(0xb80)
 #define DMAE0_IRQ	evt2irq(0xbc0)	/* DMA Error IRQ*/
 #define SH_DMAC_BASE0	0xFE008020
-#define SH_DMARS_BASE0	0xFE009000
 #elif defined(CONFIG_CPU_SUBTYPE_SH7722)
 #define DMTE0_IRQ	evt2irq(0x800)
 #define DMTE4_IRQ	evt2irq(0xb80)
 #define DMAE0_IRQ	evt2irq(0xbc0)	/* DMA Error IRQ*/
 #define SH_DMAC_BASE0	0xFE008020
-#define SH_DMARS_BASE0	0xFE009000
 #elif defined(CONFIG_CPU_SUBTYPE_SH7763) || \
 	defined(CONFIG_CPU_SUBTYPE_SH7764)
 #define DMTE0_IRQ	evt2irq(0x640)
 #define DMTE4_IRQ	evt2irq(0x780)
 #define DMAE0_IRQ	evt2irq(0x6c0)
 #define SH_DMAC_BASE0	0xFF608020
-#define SH_DMARS_BASE0	0xFF609000
 #elif defined(CONFIG_CPU_SUBTYPE_SH7723)
 #define DMTE0_IRQ	evt2irq(0x800)	/* DMAC0A*/
 #define DMTE4_IRQ	evt2irq(0xb80)	/* DMAC0B */
@@ -35,7 +32,6 @@
 #define DMAE1_IRQ	evt2irq(0xb40)	/* DMA Error IRQ*/
 #define SH_DMAC_BASE0	0xFE008020
 #define SH_DMAC_BASE1	0xFDC08020
-#define SH_DMARS_BASE0	0xFDC09000
 #elif defined(CONFIG_CPU_SUBTYPE_SH7724)
 #define DMTE0_IRQ	evt2irq(0x800)	/* DMAC0A*/
 #define DMTE4_IRQ	evt2irq(0xb80)	/* DMAC0B */
@@ -48,8 +44,6 @@
 #define DMAE1_IRQ	evt2irq(0xb40)	/* DMA Error IRQ*/
 #define SH_DMAC_BASE0	0xFE008020
 #define SH_DMAC_BASE1	0xFDC08020
-#define SH_DMARS_BASE0	0xFE009000
-#define SH_DMARS_BASE1	0xFDC09000
 #elif defined(CONFIG_CPU_SUBTYPE_SH7780)
 #define DMTE0_IRQ	evt2irq(0x640)
 #define DMTE4_IRQ	evt2irq(0x780)
@@ -61,7 +55,6 @@
 #define DMAE0_IRQ	evt2irq(0x6c0)	/* DMA Error IRQ */
 #define SH_DMAC_BASE0	0xFC808020
 #define SH_DMAC_BASE1	0xFC818020
-#define SH_DMARS_BASE0	0xFC809000
 #else /* SH7785 */
 #define DMTE0_IRQ	evt2irq(0x620)
 #define DMTE4_IRQ	evt2irq(0x6a0)
@@ -74,7 +67,6 @@
 #define DMAE1_IRQ	evt2irq(0x940)	/* DMA Error IRQ1 */
 #define SH_DMAC_BASE0	0xFC808020
 #define SH_DMAC_BASE1	0xFCC08020
-#define SH_DMARS_BASE0	0xFC809000
 #endif
 
 #endif /* __ASM_SH_CPU_SH4_DMA_SH7780_H */