aboutsummaryrefslogtreecommitdiff
path: root/arch/sh/drivers/dma/dma-sh.c
diff options
context:
space:
mode:
authorPaul Mundt <lethal@linux-sh.org>2006-01-16 22:14:09 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-01-16 23:15:27 -0800
commit0d831770b154a057562236e8cf50905c8f1ae1b0 (patch)
treedc25902b29b09838f2fe32e47be53c951a2fa67e /arch/sh/drivers/dma/dma-sh.c
parent0025835cf20e07056b8521b8c1d7d0bfe07e81f1 (diff)
[PATCH] sh: DMA updates
This extends the current SH DMA API somewhat to support a proper virtual channel abstraction, and also works to represent this through the driver model by giving each DMAC its own platform device. There's also a few other minor changes to support a few new CPU subtypes, and make TEI generation for the SH DMAC configurable. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/sh/drivers/dma/dma-sh.c')
-rw-r--r--arch/sh/drivers/dma/dma-sh.c134
1 files changed, 82 insertions, 52 deletions
diff --git a/arch/sh/drivers/dma/dma-sh.c b/arch/sh/drivers/dma/dma-sh.c
index 31dacd4444b..cca26c4c9d1 100644
--- a/arch/sh/drivers/dma/dma-sh.c
+++ b/arch/sh/drivers/dma/dma-sh.c
@@ -5,6 +5,7 @@
*
* Copyright (C) 2000 Takashi YOSHII
* Copyright (C) 2003, 2004 Paul Mundt
+ * Copyright (C) 2005 Andriy Skulysh
*
* 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
@@ -16,51 +17,28 @@
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/module.h>
+#include <asm/dreamcast/dma.h>
#include <asm/signal.h>
#include <asm/irq.h>
#include <asm/dma.h>
#include <asm/io.h>
#include "dma-sh.h"
-/*
- * The SuperH DMAC supports a number of transmit sizes, we list them here,
- * with their respective values as they appear in the CHCR registers.
- *
- * Defaults to a 64-bit transfer size.
- */
-enum {
- XMIT_SZ_64BIT,
- XMIT_SZ_8BIT,
- XMIT_SZ_16BIT,
- XMIT_SZ_32BIT,
- XMIT_SZ_256BIT,
-};
-
-/*
- * The DMA count is defined as the number of bytes to transfer.
- */
-static unsigned int ts_shift[] = {
- [XMIT_SZ_64BIT] = 3,
- [XMIT_SZ_8BIT] = 0,
- [XMIT_SZ_16BIT] = 1,
- [XMIT_SZ_32BIT] = 2,
- [XMIT_SZ_256BIT] = 5,
-};
-
static inline unsigned int get_dmte_irq(unsigned int chan)
{
- unsigned int irq;
+ unsigned int irq = 0;
/*
* Normally we could just do DMTE0_IRQ + chan outright, though in the
* case of the 7751R, the DMTE IRQs for channels > 4 start right above
* the SCIF
*/
-
if (chan < 4) {
irq = DMTE0_IRQ + chan;
} else {
+#ifdef DMTE4_IRQ
irq = DMTE4_IRQ + chan - 4;
+#endif
}
return irq;
@@ -78,9 +56,7 @@ static inline unsigned int calc_xmit_shift(struct dma_channel *chan)
{
u32 chcr = ctrl_inl(CHCR[chan->chan]);
- chcr >>= 4;
-
- return ts_shift[chcr & 0x0007];
+ return ts_shift[(chcr & CHCR_TS_MASK)>>CHCR_TS_SHIFT];
}
/*
@@ -109,8 +85,13 @@ static irqreturn_t dma_tei(int irq, void *dev_id, struct pt_regs *regs)
static int sh_dmac_request_dma(struct dma_channel *chan)
{
+ char name[32];
+
+ snprintf(name, sizeof(name), "DMAC Transfer End (Channel %d)",
+ chan->chan);
+
return request_irq(get_dmte_irq(chan->chan), dma_tei,
- SA_INTERRUPT, "DMAC Transfer End", chan);
+ SA_INTERRUPT, name, chan);
}
static void sh_dmac_free_dma(struct dma_channel *chan)
@@ -118,10 +99,18 @@ static void sh_dmac_free_dma(struct dma_channel *chan)
free_irq(get_dmte_irq(chan->chan), chan);
}
-static void sh_dmac_configure_channel(struct dma_channel *chan, unsigned long chcr)
+static void
+sh_dmac_configure_channel(struct dma_channel *chan, unsigned long chcr)
{
if (!chcr)
- chcr = RS_DUAL;
+ chcr = RS_DUAL | CHCR_IE;
+
+ if (chcr & CHCR_IE) {
+ chcr &= ~CHCR_IE;
+ chan->flags |= DMA_TEI_CAPABLE;
+ } else {
+ chan->flags &= ~DMA_TEI_CAPABLE;
+ }
ctrl_outl(chcr, CHCR[chan->chan]);
@@ -130,22 +119,32 @@ static void sh_dmac_configure_channel(struct dma_channel *chan, unsigned long ch
static void sh_dmac_enable_dma(struct dma_channel *chan)
{
- int irq = get_dmte_irq(chan->chan);
+ int irq;
u32 chcr;
chcr = ctrl_inl(CHCR[chan->chan]);
- chcr |= CHCR_DE | CHCR_IE;
+ chcr |= CHCR_DE;
+
+ if (chan->flags & DMA_TEI_CAPABLE)
+ chcr |= CHCR_IE;
+
ctrl_outl(chcr, CHCR[chan->chan]);
- enable_irq(irq);
+ if (chan->flags & DMA_TEI_CAPABLE) {
+ irq = get_dmte_irq(chan->chan);
+ enable_irq(irq);
+ }
}
static void sh_dmac_disable_dma(struct dma_channel *chan)
{
- int irq = get_dmte_irq(chan->chan);
+ int irq;
u32 chcr;
- disable_irq(irq);
+ if (chan->flags & DMA_TEI_CAPABLE) {
+ irq = get_dmte_irq(chan->chan);
+ disable_irq(irq);
+ }
chcr = ctrl_inl(CHCR[chan->chan]);
chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE);
@@ -158,7 +157,7 @@ static int sh_dmac_xfer_dma(struct dma_channel *chan)
* If we haven't pre-configured the channel with special flags, use
* the defaults.
*/
- if (!(chan->flags & DMA_CONFIGURED))
+ if (unlikely(!(chan->flags & DMA_CONFIGURED)))
sh_dmac_configure_channel(chan, 0);
sh_dmac_disable_dma(chan);
@@ -178,9 +177,11 @@ static int sh_dmac_xfer_dma(struct dma_channel *chan)
* cascading to the PVR2 DMAC. In this case, we still need to write
* SAR and DAR, regardless of value, in order for cascading to work.
*/
- if (chan->sar || (mach_is_dreamcast() && chan->chan == 2))
+ if (chan->sar || (mach_is_dreamcast() &&
+ chan->chan == PVR2_CASCADE_CHAN))
ctrl_outl(chan->sar, SAR[chan->chan]);
- if (chan->dar || (mach_is_dreamcast() && chan->chan == 2))
+ if (chan->dar || (mach_is_dreamcast() &&
+ chan->chan == PVR2_CASCADE_CHAN))
ctrl_outl(chan->dar, DAR[chan->chan]);
ctrl_outl(chan->count >> calc_xmit_shift(chan), DMATCR[chan->chan]);
@@ -198,17 +199,38 @@ static int sh_dmac_get_dma_residue(struct dma_channel *chan)
return ctrl_inl(DMATCR[chan->chan]) << calc_xmit_shift(chan);
}
-#if defined(CONFIG_CPU_SH4)
-static irqreturn_t dma_err(int irq, void *dev_id, struct pt_regs *regs)
+#ifdef CONFIG_CPU_SUBTYPE_SH7780
+#define dmaor_read_reg() ctrl_inw(DMAOR)
+#define dmaor_write_reg(data) ctrl_outw(data, DMAOR)
+#else
+#define dmaor_read_reg() ctrl_inl(DMAOR)
+#define dmaor_write_reg(data) ctrl_outl(data, DMAOR)
+#endif
+
+static inline int dmaor_reset(void)
{
- unsigned long dmaor = ctrl_inl(DMAOR);
+ unsigned long dmaor = dmaor_read_reg();
+
+ /* Try to clear the error flags first, incase they are set */
+ dmaor &= ~(DMAOR_NMIF | DMAOR_AE);
+ dmaor_write_reg(dmaor);
- printk("DMAE: DMAOR=%lx\n", dmaor);
+ dmaor |= DMAOR_INIT;
+ dmaor_write_reg(dmaor);
- ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_NMIF, DMAOR);
- ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_AE, DMAOR);
- ctrl_outl(ctrl_inl(DMAOR)|DMAOR_DME, DMAOR);
+ /* See if we got an error again */
+ if ((dmaor_read_reg() & (DMAOR_AE | DMAOR_NMIF))) {
+ printk(KERN_ERR "dma-sh: Can't initialize DMAOR.\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+#if defined(CONFIG_CPU_SH4)
+static irqreturn_t dma_err(int irq, void *dev_id, struct pt_regs *regs)
+{
+ dmaor_reset();
disable_irq(irq);
return IRQ_HANDLED;
@@ -224,8 +246,8 @@ static struct dma_ops sh_dmac_ops = {
};
static struct dma_info sh_dmac_info = {
- .name = "SuperH DMAC",
- .nr_channels = 4,
+ .name = "sh_dmac",
+ .nr_channels = CONFIG_NR_ONCHIP_DMA_CHANNELS,
.ops = &sh_dmac_ops,
.flags = DMAC_CHANNELS_TEI_CAPABLE,
};
@@ -248,7 +270,13 @@ static int __init sh_dmac_init(void)
make_ipr_irq(irq, DMA_IPR_ADDR, DMA_IPR_POS, DMA_PRIORITY);
}
- ctrl_outl(0x8000 | DMAOR_DME, DMAOR);
+ /*
+ * Initialize DMAOR, and clean up any error flags that may have
+ * been set.
+ */
+ i = dmaor_reset();
+ if (i < 0)
+ return i;
return register_dmac(info);
}
@@ -258,10 +286,12 @@ static void __exit sh_dmac_exit(void)
#ifdef CONFIG_CPU_SH4
free_irq(DMAE_IRQ, 0);
#endif
+ unregister_dmac(&sh_dmac_info);
}
subsys_initcall(sh_dmac_init);
module_exit(sh_dmac_exit);
+MODULE_AUTHOR("Takashi YOSHII, Paul Mundt, Andriy Skulysh");
+MODULE_DESCRIPTION("SuperH On-Chip DMAC Support");
MODULE_LICENSE("GPL");
-