[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>

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);