summaryrefslogtreecommitdiff
path: root/arch/arm/kernel/dma-isa.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/kernel/dma-isa.c
downloadconfigs-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/kernel/dma-isa.c')
-rw-r--r--arch/arm/kernel/dma-isa.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/arch/arm/kernel/dma-isa.c b/arch/arm/kernel/dma-isa.c
new file mode 100644
index 00000000000..e9a36304ec3
--- /dev/null
+++ b/arch/arm/kernel/dma-isa.c
@@ -0,0 +1,207 @@
+/*
+ * 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/pci.h>
+
+#include <asm/dma.h>
+#include <asm/io.h>
+
+#include <asm/mach/dma.h>
+
+#define ISA_DMA_MODE_READ 0x44
+#define ISA_DMA_MODE_WRITE 0x48
+#define ISA_DMA_MODE_CASCADE 0xc0
+#define ISA_DMA_AUTOINIT 0x10
+
+#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(dmach_t channel, dma_t *dma)
+{
+ unsigned int io_port = isa_dma_port[channel][ISA_DMA_COUNT];
+ int count;
+
+ count = 1 + inb(io_port);
+ count |= inb(io_port) << 8;
+
+ return channel < 4 ? count : (count << 1);
+}
+
+static void isa_enable_dma(dmach_t channel, dma_t *dma)
+{
+ if (dma->invalid) {
+ unsigned long address, length;
+ unsigned int mode, direction;
+
+ mode = channel & 3;
+ switch (dma->dma_mode & DMA_MODE_MASK) {
+ case DMA_MODE_READ:
+ mode |= ISA_DMA_MODE_READ;
+ direction = PCI_DMA_FROMDEVICE;
+ break;
+
+ case DMA_MODE_WRITE:
+ mode |= ISA_DMA_MODE_WRITE;
+ direction = PCI_DMA_TODEVICE;
+ break;
+
+ case DMA_MODE_CASCADE:
+ mode |= ISA_DMA_MODE_CASCADE;
+ direction = PCI_DMA_BIDIRECTIONAL;
+ break;
+
+ default:
+ direction = PCI_DMA_NONE;
+ break;
+ }
+
+ if (!dma->using_sg) {
+ /*
+ * Cope with ISA-style drivers which expect cache
+ * coherence.
+ */
+ dma->buf.dma_address = pci_map_single(NULL,
+ dma->buf.__address, dma->buf.length,
+ direction);
+ }
+
+ address = dma->buf.dma_address;
+ length = dma->buf.length - 1;
+
+ outb(address >> 16, isa_dma_port[channel][ISA_DMA_PGLO]);
+ outb(address >> 24, isa_dma_port[channel][ISA_DMA_PGHI]);
+
+ if (channel >= 4) {
+ address >>= 1;
+ length >>= 1;
+ }
+
+ outb(0, isa_dma_port[channel][ISA_DMA_CLRFF]);
+
+ outb(address, isa_dma_port[channel][ISA_DMA_ADDR]);
+ outb(address >> 8, isa_dma_port[channel][ISA_DMA_ADDR]);
+
+ outb(length, isa_dma_port[channel][ISA_DMA_COUNT]);
+ outb(length >> 8, isa_dma_port[channel][ISA_DMA_COUNT]);
+
+ if (dma->dma_mode & DMA_AUTOINIT)
+ mode |= ISA_DMA_AUTOINIT;
+
+ outb(mode, isa_dma_port[channel][ISA_DMA_MODE]);
+ dma->invalid = 0;
+ }
+ outb(channel & 3, isa_dma_port[channel][ISA_DMA_MASK]);
+}
+
+static void isa_disable_dma(dmach_t channel, dma_t *dma)
+{
+ outb(channel | 4, isa_dma_port[channel][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[] = {
+ { "dma1", 0x0000, 0x000f },
+ { "dma low page", 0x0080, 0x008f },
+ { "dma2", 0x00c0, 0x00df },
+ { "dma high page", 0x0480, 0x048f }
+};
+
+void __init isa_init_dma(dma_t *dma)
+{
+ /*
+ * 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) {
+ int channel, i;
+
+ for (channel = 0; channel < 8; channel++) {
+ dma[channel].d_ops = &isa_dma_ops;
+ isa_disable_dma(channel, 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);
+
+ request_dma(DMA_ISA_CASCADE, "cascade");
+
+ for (i = 0; i < sizeof(dma_resources) / sizeof(dma_resources[0]); i++)
+ request_resource(&ioport_resource, dma_resources + i);
+ }
+}