Initial import

1 files changed, 222 insertions, 0 deletions

diff --git a/arch/arm/kernel/dma-isa.c b/arch/arm/kernel/dma-isa.c
new file mode 100644
index 000000000..84363fe7b
--- /dev/null
+++ b/arch/arm/kernel/dma-isa.c
@@ -0,0 +1,222 @@
+/*
+ *  linux/arch/arm/kernel/dma-isa.c
+ *
+ *  Copyright (C) 1999-2000 Russell King
+ *
+ * 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.
+ *
+ *  ISA DMA primitives
+ *  Taken from various sources, including:
+ *   linux/include/asm/dma.h: Defines for using and allocating dma channels.
+ *     Written by Hennus Bergman, 1992.
+ *     High DMA channel support & info by Hannu Savolainen and John Boyd,
+ *     Nov. 1992.
+ *   arch/arm/kernel/dma-ebsa285.c
+ *   Copyright (C) 1998 Phil Blundell
+ */
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+
+#include <asm/dma.h>
+#include <asm/mach/dma.h>
+
+#define ISA_DMA_MASK		0
+#define ISA_DMA_MODE		1
+#define ISA_DMA_CLRFF		2
+#define ISA_DMA_PGHI		3
+#define ISA_DMA_PGLO		4
+#define ISA_DMA_ADDR		5
+#define ISA_DMA_COUNT		6
+
+static unsigned int isa_dma_port[8][7] = {
+	/* MASK   MODE   CLRFF  PAGE_HI PAGE_LO ADDR COUNT */
+	{  0x0a,  0x0b,  0x0c,  0x487,  0x087,  0x00, 0x01 },
+	{  0x0a,  0x0b,  0x0c,  0x483,  0x083,  0x02, 0x03 },
+	{  0x0a,  0x0b,  0x0c,  0x481,  0x081,  0x04, 0x05 },
+	{  0x0a,  0x0b,  0x0c,  0x482,  0x082,  0x06, 0x07 },
+	{  0xd4,  0xd6,  0xd8,  0x000,  0x000,  0xc0, 0xc2 },
+	{  0xd4,  0xd6,  0xd8,  0x48b,  0x08b,  0xc4, 0xc6 },
+	{  0xd4,  0xd6,  0xd8,  0x489,  0x089,  0xc8, 0xca },
+	{  0xd4,  0xd6,  0xd8,  0x48a,  0x08a,  0xcc, 0xce }
+};
+
+static int isa_get_dma_residue(unsigned int chan, dma_t *dma)
+{
+	unsigned int io_port = isa_dma_port[chan][ISA_DMA_COUNT];
+	int count;
+
+	count = 1 + inb(io_port);
+	count |= inb(io_port) << 8;
+
+	return chan < 4 ? count : (count << 1);
+}
+
+static void isa_enable_dma(unsigned int chan, dma_t *dma)
+{
+	if (dma->invalid) {
+		unsigned long address, length;
+		unsigned int mode;
+		enum dma_data_direction direction;
+
+		mode = (chan & 3) | dma->dma_mode;
+		switch (dma->dma_mode & DMA_MODE_MASK) {
+		case DMA_MODE_READ:
+			direction = DMA_FROM_DEVICE;
+			break;
+
+		case DMA_MODE_WRITE:
+			direction = DMA_TO_DEVICE;
+			break;
+
+		case DMA_MODE_CASCADE:
+			direction = DMA_BIDIRECTIONAL;
+			break;
+
+		default:
+			direction = DMA_NONE;
+			break;
+		}
+
+		if (!dma->sg) {
+			/*
+			 * Cope with ISA-style drivers which expect cache
+			 * coherence.
+			 */
+			dma->sg = &dma->buf;
+			dma->sgcount = 1;
+			dma->buf.length = dma->count;
+			dma->buf.dma_address = dma_map_single(NULL,
+				dma->addr, dma->count,
+				direction);
+		}
+
+		address = dma->buf.dma_address;
+		length  = dma->buf.length - 1;
+
+		outb(address >> 16, isa_dma_port[chan][ISA_DMA_PGLO]);
+		outb(address >> 24, isa_dma_port[chan][ISA_DMA_PGHI]);
+
+		if (chan >= 4) {
+			address >>= 1;
+			length >>= 1;
+		}
+
+		outb(0, isa_dma_port[chan][ISA_DMA_CLRFF]);
+
+		outb(address, isa_dma_port[chan][ISA_DMA_ADDR]);
+		outb(address >> 8, isa_dma_port[chan][ISA_DMA_ADDR]);
+
+		outb(length, isa_dma_port[chan][ISA_DMA_COUNT]);
+		outb(length >> 8, isa_dma_port[chan][ISA_DMA_COUNT]);
+
+		outb(mode, isa_dma_port[chan][ISA_DMA_MODE]);
+		dma->invalid = 0;
+	}
+	outb(chan & 3, isa_dma_port[chan][ISA_DMA_MASK]);
+}
+
+static void isa_disable_dma(unsigned int chan, dma_t *dma)
+{
+	outb(chan | 4, isa_dma_port[chan][ISA_DMA_MASK]);
+}
+
+static struct dma_ops isa_dma_ops = {
+	.type		= "ISA",
+	.enable		= isa_enable_dma,
+	.disable	= isa_disable_dma,
+	.residue	= isa_get_dma_residue,
+};
+
+static struct resource dma_resources[] = { {
+	.name	= "dma1",
+	.start	= 0x0000,
+	.end	= 0x000f
+}, {
+	.name	= "dma low page",
+	.start	= 0x0080,
+	.end 	= 0x008f
+}, {
+	.name	= "dma2",
+	.start	= 0x00c0,
+	.end	= 0x00df
+}, {
+	.name	= "dma high page",
+	.start	= 0x0480,
+	.end	= 0x048f
+} };
+
+static dma_t isa_dma[8];
+
+/*
+ * ISA DMA always starts at channel 0
+ */
+void __init isa_init_dma(void)
+{
+	/*
+	 * Try to autodetect presence of an ISA DMA controller.
+	 * We do some minimal initialisation, and check that
+	 * channel 0's DMA address registers are writeable.
+	 */
+	outb(0xff, 0x0d);
+	outb(0xff, 0xda);
+
+	/*
+	 * Write high and low address, and then read them back
+	 * in the same order.
+	 */
+	outb(0x55, 0x00);
+	outb(0xaa, 0x00);
+
+	if (inb(0) == 0x55 && inb(0) == 0xaa) {
+		unsigned int chan, i;
+
+		for (chan = 0; chan < 8; chan++) {
+			isa_dma[chan].d_ops = &isa_dma_ops;
+			isa_disable_dma(chan, NULL);
+		}
+
+		outb(0x40, 0x0b);
+		outb(0x41, 0x0b);
+		outb(0x42, 0x0b);
+		outb(0x43, 0x0b);
+
+		outb(0xc0, 0xd6);
+		outb(0x41, 0xd6);
+		outb(0x42, 0xd6);
+		outb(0x43, 0xd6);
+
+		outb(0, 0xd4);
+
+		outb(0x10, 0x08);
+		outb(0x10, 0xd0);
+
+		/*
+		 * Is this correct?  According to my documentation, it
+		 * doesn't appear to be.  It should be:
+		 *  outb(0x3f, 0x40b); outb(0x3f, 0x4d6);
+		 */
+		outb(0x30, 0x40b);
+		outb(0x31, 0x40b);
+		outb(0x32, 0x40b);
+		outb(0x33, 0x40b);
+		outb(0x31, 0x4d6);
+		outb(0x32, 0x4d6);
+		outb(0x33, 0x4d6);
+
+		for (i = 0; i < ARRAY_SIZE(dma_resources); i++)
+			request_resource(&ioport_resource, dma_resources + i);
+
+		for (chan = 0; chan < 8; chan++) {
+			int ret = isa_dma_add(chan, &isa_dma[chan]);
+			if (ret)
+				pr_err("ISADMA%u: unable to register: %d\n",
+				       chan, ret);
+		}
+
+		request_dma(DMA_ISA_CASCADE, "cascade");
+	}
+}