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authorEric Miao <eric.y.miao@gmail.com>2007-06-22 05:40:17 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2007-07-12 14:28:16 +0100
commitf53f066c25036210036730d64c876ea586114425 (patch)
treee680deb53ff12ec09f5c64421a3f13eecb7aed41 /arch
parentcd49104d99b56383a3b1fdce2f31018197093c31 (diff)
downloadop-kernel-dev-f53f066c25036210036730d64c876ea586114425.zip
op-kernel-dev-f53f066c25036210036730d64c876ea586114425.tar.gz
[ARM] 4451/1: pxa: make dma.c generic and remove cpu specific dma code
Since the number of dma channels varies between pxa25x and pxa27x, it introduces some specific code in dma.c. This patch moves the specific code to pxa25x.c and pxa27x.c and makes dma.c more generic. 1. add pxa_init_dma() for dma initialization, the number of channels are passed in by the argument 2. add a "prio" field to the "struct pxa_dma_channel" for the channel priority, and is initialized in pxa_init_dma() 3. use a general priority comparison with the channels "prio" field so to remove the processor specific pxa_for_each_dma_prio macro, this is not lightning fast as the original one, but it is acceptable as it happens when requesting dma, which is usually not so performance critical Signed-off-by: eric miao <eric.miao@marvell.com> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/mach-pxa/dma.c44
-rw-r--r--arch/arm/mach-pxa/pxa25x.c5
-rw-r--r--arch/arm/mach-pxa/pxa27x.c3
3 files changed, 39 insertions, 13 deletions
diff --git a/arch/arm/mach-pxa/dma.c b/arch/arm/mach-pxa/dma.c
index 4440bab..93c4f31 100644
--- a/arch/arm/mach-pxa/dma.c
+++ b/arch/arm/mach-pxa/dma.c
@@ -25,12 +25,15 @@
#include <asm/arch/pxa-regs.h>
-static struct dma_channel {
+struct dma_channel {
char *name;
+ pxa_dma_prio prio;
void (*irq_handler)(int, void *);
void *data;
-} dma_channels[PXA_DMA_CHANNELS];
+};
+static struct dma_channel *dma_channels;
+static int num_dma_channels;
int pxa_request_dma (char *name, pxa_dma_prio prio,
void (*irq_handler)(int, void *),
@@ -47,8 +50,9 @@ int pxa_request_dma (char *name, pxa_dma_prio prio,
do {
/* try grabbing a DMA channel with the requested priority */
- pxa_for_each_dma_prio (i, prio) {
- if (!dma_channels[i].name) {
+ for (i = 0; i < num_dma_channels; i++) {
+ if ((dma_channels[i].prio == prio) &&
+ !dma_channels[i].name) {
found = 1;
break;
}
@@ -91,7 +95,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
{
int i, dint = DINT;
- for (i = 0; i < PXA_DMA_CHANNELS; i++) {
+ for (i = 0; i < num_dma_channels; i++) {
if (dint & (1 << i)) {
struct dma_channel *channel = &dma_channels[i];
if (channel->name && channel->irq_handler) {
@@ -109,18 +113,32 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}
-static int __init pxa_dma_init (void)
+int __init pxa_init_dma(int num_ch)
{
- int ret;
+ int i, ret;
- ret = request_irq (IRQ_DMA, dma_irq_handler, 0, "DMA", NULL);
- if (ret)
+ dma_channels = kzalloc(sizeof(struct dma_channel) * num_ch, GFP_KERNEL);
+ if (dma_channels == NULL)
+ return -ENOMEM;
+
+ ret = request_irq(IRQ_DMA, dma_irq_handler, IRQF_DISABLED, "DMA", NULL);
+ if (ret) {
printk (KERN_CRIT "Wow! Can't register IRQ for DMA\n");
- return ret;
-}
+ kfree(dma_channels);
+ return ret;
+ }
-arch_initcall(pxa_dma_init);
+ /* dma channel priorities on pxa2xx processors:
+ * ch 0 - 3, 16 - 19 <--> (0) DMA_PRIO_HIGH
+ * ch 4 - 7, 20 - 23 <--> (1) DMA_PRIO_MEDIUM
+ * ch 8 - 15, 24 - 31 <--> (2) DMA_PRIO_LOW
+ */
+ for (i = 0; i < num_ch; i++)
+ dma_channels[i].prio = min((i & 0xf) >> 2, DMA_PRIO_LOW);
+
+ num_dma_channels = num_ch;
+ return 0;
+}
EXPORT_SYMBOL(pxa_request_dma);
EXPORT_SYMBOL(pxa_free_dma);
-
diff --git a/arch/arm/mach-pxa/pxa25x.c b/arch/arm/mach-pxa/pxa25x.c
index a8796ae..1343758 100644
--- a/arch/arm/mach-pxa/pxa25x.c
+++ b/arch/arm/mach-pxa/pxa25x.c
@@ -25,6 +25,7 @@
#include <asm/arch/irqs.h>
#include <asm/arch/pxa-regs.h>
#include <asm/arch/pm.h>
+#include <asm/arch/dma.h>
#include "generic.h"
@@ -137,7 +138,11 @@ void __init pxa25x_init_irq(void)
static int __init pxa25x_init(void)
{
+ int ret = 0;
+
if (cpu_is_pxa21x() || cpu_is_pxa25x()) {
+ if ((ret = pxa_init_dma(16)))
+ return ret;
#ifdef CONFIG_PM
pm_set_ops(&pxa25x_pm_ops);
#endif
diff --git a/arch/arm/mach-pxa/pxa27x.c b/arch/arm/mach-pxa/pxa27x.c
index 1407985..5b819e2 100644
--- a/arch/arm/mach-pxa/pxa27x.c
+++ b/arch/arm/mach-pxa/pxa27x.c
@@ -23,6 +23,7 @@
#include <asm/arch/pxa-regs.h>
#include <asm/arch/ohci.h>
#include <asm/arch/pm.h>
+#include <asm/arch/dma.h>
#include "generic.h"
@@ -214,6 +215,8 @@ static int __init pxa27x_init(void)
{
int ret = 0;
if (cpu_is_pxa27x()) {
+ if ((ret = pxa_init_dma(32)))
+ return ret;
#ifdef CONFIG_PM
pm_set_ops(&pxa27x_pm_ops);
#endif
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