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authorEric Miao <eric.miao@marvell.com>2009-01-20 12:06:01 +0800
committerEric Miao <eric.miao@marvell.com>2009-03-23 10:11:31 +0800
commitbd5ce4332328c1fe473690a86b2e6a4157be038f (patch)
tree785aa105d3752b2df92b1792e799e3f39e1b0411 /arch/arm/mach-pxa/dma.c
parente2bb5befd7b0ae2d045f4413a97db52340edec13 (diff)
[ARM] pxa: introduce plat-pxa for PXA common code and add DMA support
1. introduce folder of 'arch/arm/plat-pxa' for common code across different PXA processor families 2. initially moved DMA code into plat-pxa 3. common code in <mach/dma.h> moved into <plat/dma.h>, new processors should implement its own <mach/dma.h>, provide the following required definitions and '#include <plat/dma.h>' in the end: - DMAC_REGS_VIRT for mapped virtual address of the DMA registers' physical I/O memory Signed-off-by: Eric Miao <eric.miao@marvell.com>
Diffstat (limited to 'arch/arm/mach-pxa/dma.c')
-rw-r--r--arch/arm/mach-pxa/dma.c144
1 files changed, 0 insertions, 144 deletions
diff --git a/arch/arm/mach-pxa/dma.c b/arch/arm/mach-pxa/dma.c
deleted file mode 100644
index 01217e01f7d..00000000000
--- a/arch/arm/mach-pxa/dma.c
+++ /dev/null
@@ -1,144 +0,0 @@
-/*
- * linux/arch/arm/mach-pxa/dma.c
- *
- * PXA DMA registration and IRQ dispatching
- *
- * Author: Nicolas Pitre
- * Created: Nov 15, 2001
- * Copyright: MontaVista Software Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/interrupt.h>
-#include <linux/errno.h>
-
-#include <asm/system.h>
-#include <asm/irq.h>
-#include <mach/hardware.h>
-#include <mach/dma.h>
-
-struct dma_channel {
- char *name;
- pxa_dma_prio prio;
- void (*irq_handler)(int, void *);
- void *data;
-};
-
-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 *),
- void *data)
-{
- unsigned long flags;
- int i, found = 0;
-
- /* basic sanity checks */
- if (!name || !irq_handler)
- return -EINVAL;
-
- local_irq_save(flags);
-
- do {
- /* try grabbing a DMA channel with the requested priority */
- for (i = 0; i < num_dma_channels; i++) {
- if ((dma_channels[i].prio == prio) &&
- !dma_channels[i].name) {
- found = 1;
- break;
- }
- }
- /* if requested prio group is full, try a hier priority */
- } while (!found && prio--);
-
- if (found) {
- DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
- dma_channels[i].name = name;
- dma_channels[i].irq_handler = irq_handler;
- dma_channels[i].data = data;
- } else {
- printk (KERN_WARNING "No more available DMA channels for %s\n", name);
- i = -ENODEV;
- }
-
- local_irq_restore(flags);
- return i;
-}
-
-void pxa_free_dma (int dma_ch)
-{
- unsigned long flags;
-
- if (!dma_channels[dma_ch].name) {
- printk (KERN_CRIT
- "%s: trying to free channel %d which is already freed\n",
- __func__, dma_ch);
- return;
- }
-
- local_irq_save(flags);
- DCSR(dma_ch) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
- dma_channels[dma_ch].name = NULL;
- local_irq_restore(flags);
-}
-
-static irqreturn_t dma_irq_handler(int irq, void *dev_id)
-{
- int i, dint = DINT;
-
- 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) {
- channel->irq_handler(i, channel->data);
- } else {
- /*
- * IRQ for an unregistered DMA channel:
- * let's clear the interrupts and disable it.
- */
- printk (KERN_WARNING "spurious IRQ for DMA channel %d\n", i);
- DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
- }
- }
- }
- return IRQ_HANDLED;
-}
-
-int __init pxa_init_dma(int irq, int num_ch)
-{
- int i, ret;
-
- dma_channels = kzalloc(sizeof(struct dma_channel) * num_ch, GFP_KERNEL);
- if (dma_channels == NULL)
- return -ENOMEM;
-
- /* 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++) {
- DCSR(i) = 0;
- dma_channels[i].prio = min((i & 0xf) >> 2, DMA_PRIO_LOW);
- }
-
- ret = request_irq(irq, dma_irq_handler, IRQF_DISABLED, "DMA", NULL);
- if (ret) {
- printk (KERN_CRIT "Wow! Can't register IRQ for DMA\n");
- kfree(dma_channels);
- return ret;
- }
-
- num_dma_channels = num_ch;
- return 0;
-}
-
-EXPORT_SYMBOL(pxa_request_dma);
-EXPORT_SYMBOL(pxa_free_dma);