/*
* Mips Jazz DMA controller support
* Copyright (C) 1995, 1996 by Andreas Busse
*
* NOTE: Some of the argument checking could be removed when
* things have settled down. Also, instead of returning 0xffffffff
* on failure of vdma_alloc() one could leave page #0 unused
* and return the more usual NULL pointer as logical address.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/spinlock.h>
#include <linux/gfp.h>
#include <asm/mipsregs.h>
#include <asm/jazz.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/dma.h>
#include <asm/jazzdma.h>
#include <asm/pgtable.h>
/*
* Set this to one to enable additional vdma debug code.
*/
#define CONF_DEBUG_VDMA 0
static VDMA_PGTBL_ENTRY *pgtbl;
static DEFINE_SPINLOCK(vdma_lock);
/*
* Debug stuff
*/
#define vdma_debug ((CONF_DEBUG_VDMA) ? debuglvl : 0)
static int debuglvl = 3;
/*
* Initialize the pagetable with a one-to-one mapping of
* the first 16 Mbytes of main memory and declare all
* entries to be unused. Using this method will at least
* allow some early device driver operations to work.
*/
static inline void vdma_pgtbl_init(void)
{
unsigned long paddr = 0;
int i;
for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
pgtbl[i].frame = paddr;
pgtbl[i].owner = VDMA_PAGE_EMPTY;
paddr += VDMA_PAGESIZE;
}
}
/*
* Initialize the Jazz R4030 dma controller
*/
static int __init vdma_init(void)
{
/*
* Allocate 32k of memory for DMA page tables. This needs to be page
* aligned and should be uncached to avoid cache flushing after every
* update.
*/
pgtbl = (VDMA_PGTBL_ENTRY *)__get_free_pages(GFP_KERNEL | GFP_DMA,
get_order(VDMA_PGTBL_SIZE));
BUG_ON(!pgtbl);
dma_cache_wback_inv((unsigned long)pgtbl, VDMA_PGTBL_SIZE);
pgtbl = (VDMA_PGTBL_ENTRY *)KSEG1ADDR(pgtbl);
/*
* Clear the R4030 translation table
*/
vdma_pgtbl_init();
r4030_write_reg32(JAZZ_R4030_TRSTBL_BASE, CPHYSADDR(pgtbl));
r4030_write_reg32(JAZZ_R4030_TRSTBL_LIM, VDMA_PGTBL_SIZE);
r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
printk(KERN_INFO "VDMA: R4030 DMA pagetables initialized.\n");
return 0;
}
/*
* Allocate DMA pagetables using a simple first-fit algorithm
*/
unsigned long vdma_alloc(unsigned long paddr, unsigned long size)
{
int first, last, pages, frame, i;
unsigned long laddr, flags;
/* check arguments */
if (paddr > 0x1fffffff) {
if (vdma_debug)
printk("vdma_alloc: Invalid physical address: %08lx\n",
paddr);
return VDMA_ERROR; /* invalid physical address */
}
if (size > 0x400000 || size == 0) {
if (vdma_debug)
printk("vdma_alloc: Invalid size: %08lx\n", size);
return VDMA_ERROR; /* invalid physical address */
}
spin_lock_irqsave(&vdma_lock, flags);
/*
* Find free chunk
*/
pages = VDMA_PAGE(paddr + size) - VDMA_PAGE(paddr) + 1;
first = 0;
while (1) {
while (pgtbl[first].owner != VDMA_PAGE_EMPTY &&
first < VDMA_PGTBL_ENTRIES) first++;
if (first + pages > VDMA_PGTBL_ENTRIES) { /* nothing free */
spin_unlock_irqrestore(&vdma_lock, flags);
return VDMA_ERROR;
}
last = first + 1;
while (pgtbl[last].owner == VDMA_PAGE_EMPTY
&& last - first < pages)
last++;
if (last - first == pages)
break; /* found */
first = last + 1;
}
/*
* Mark pages as allocated
*/
laddr = (first << 12) + (paddr & (VDMA_PAGESIZE - 1));
frame = paddr & ~(VDMA_PAGESIZE - 1);
for (i = first; i < last; i++) {
pgtbl[i].frame = frame;
pgtbl[i].owner = laddr;
frame += VDMA_PAGESIZE;
}
/*
* Update translation table and return logical start address
*/
r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
if (vdma_debug > 1)
printk("vdma_alloc: Allocated %d pages starting from %08lx\n",
pages, laddr);
if (vdma_debug > 2) {
printk("LADDR: ");
for (i = first; i < last; i++)
printk("%08x ", i << 12);
printk("\nPADDR: ");
for (i = first; i < last; i++)
printk("%08x ", pgtbl[i].frame);
printk("\nOWNER: ");
for (i = first; i < last; i++)
printk("%08x ", pgtbl[i].owner);
printk("\n");
}
spin_unlock_irqrestore(&vdma_lock, flags);
return laddr;
}
EXPORT_SYMBOL(vdma_alloc);
/*
* Free previously allocated dma translation pages
* Note that this does NOT change the translation table,
* it just marks the free'd pages as unused!
*/
int vdma_free(unsigned long laddr)
{
int i;
i = laddr >> 12;
if (pgtbl[i].owner != laddr) {
printk
("vdma_free: trying to free other's dma pages, laddr=%8lx\n",
laddr);
return -1;
}
while (i < VDMA_PGTBL_ENTRIES && pgtbl[i].owner == laddr) {
pgtbl[i].owner = VDMA_PAGE_EMPTY;
i++;
}
if (vdma_debug > 1)
printk("vdma_free: freed %ld pages starting from %08lx\n",
i - (laddr >> 12), laddr);
return 0;
}
EXPORT_SYMBOL(vdma_free);
/*
* Map certain page(s) to another physical address.
* Caller must have allocated the page(s) before.
*/
int vdma_remap(unsigned long laddr, unsigned long paddr, unsigned long size)
{
int first, pages;
if (laddr > 0xffffff) {
if (vdma_debug)
printk
("vdma_map: Invalid logical address: %08lx\n",
laddr);
return -EINVAL; /* invalid logical address */
}
if (paddr > 0x1fffffff) {
if (vdma_debug)
printk
("vdma_map: Invalid physical address: %08lx\n",
paddr);
return -EINVAL; /* invalid physical address */
}
pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
first = laddr >> 12;
if (vdma_debug)
printk("vdma_remap: first=%x, pages=%x\n", first, pages);
if (first + pages > VDMA_PGTBL_ENTRIES) {
if (vdma_debug)
printk("vdma_alloc: Invalid size: %08lx\n", size);
return -EINVAL;
}
paddr &= ~(VDMA_PAGESIZE - 1);
while (pages > 0 && first < VDMA_PGTBL_ENTRIES) {
if (pgtbl[first].owner != laddr) {
if (vdma_debug)
printk("Trying to remap other's pages.\n");
return -EPERM; /* not owner */
}
pgtbl[first].frame = paddr;
paddr += VDMA_PAGESIZE;
first++;
pages--;
}
/*
* Update translation table
*/
r4030_write_reg32(JAZZ_R4030_TRSTBL_INV, 0);
if (vdma_debug > 2) {
int i;
pages = (((paddr & (VDMA_PAGESIZE - 1)) + size) >> 12) + 1;
first = laddr >> 12;
printk("LADDR: ");
for (i = first; i < first + pages; i++)
printk("%08x ", i << 12);
printk("\nPADDR: ");
for (i = first; i < first + pages; i++)
printk("%08x ", pgtbl[i].frame);
printk("\nOWNER: ");
for (i = first; i < first + pages; i++)
printk("%08x ", pgtbl[i].owner);
printk("\n");
}
return 0;
}
/*
* Translate a physical address to a logical address.
* This will return the logical address of the first
* match.
*/
unsigned long vdma_phys2log(unsigned long paddr)
{
int i;
int frame;
frame = paddr & ~(VDMA_PAGESIZE - 1);
for (i = 0; i < VDMA_PGTBL_ENTRIES; i++) {
if (pgtbl[i].frame == frame)
break;
}
if (i == VDMA_PGTBL_ENTRIES)
return ~0UL;
return (i << 12) + (paddr & (VDMA_PAGESIZE - 1));
}
EXPORT_SYMBOL(vdma_phys2log);
/*
* Translate a logical DMA address to a physical address
*/
unsigned long vdma_log2phys(unsigned long laddr)
{
return pgtbl[laddr >> 12].frame + (laddr & (VDMA_PAGESIZE - 1));
}
EXPORT_SYMBOL(vdma_log2phys);
/*
* Print DMA statistics
*/
void vdma_stats(void)
{
int i;
printk("vdma_stats: CONFIG: %08x\n",
r4030_read_reg32(JAZZ_R4030_CONFIG));
printk("R4030 translation table base: %08x\n",
r4030_read_reg32(JAZZ_R4030_TRSTBL_BASE));
printk("R4030 translation table limit: %08x\n",
r4030_read_reg32(JAZZ_R4030_TRSTBL_LIM));
printk("vdma_stats: INV_ADDR: %08x\n",
r4030_read_reg32(JAZZ_R4030_INV_ADDR));
printk("vdma_stats: R_FAIL_ADDR: %08x\n",
r4030_read_reg32(JAZZ_R4030_R_FAIL_ADDR));
printk("vdma_stats: M_FAIL_ADDR: %08x\n",
r4030_read_reg32(JAZZ_R4030_M_FAIL_ADDR));
printk("vdma_stats: IRQ_SOURCE: %08x\n",
r4030_read_reg32(JAZZ_R4030_IRQ_SOURCE));
printk("vdma_stats: I386_ERROR: %08x\n",
r4030_read_reg32(JAZZ_R4030_I386_ERROR));
printk("vdma_chnl_modes: ");
for (i = 0; i < 8; i++)
printk("%04x ",
(unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
(i << 5)));
printk("\n");
printk("vdma_chnl_enables: ");
for (i = 0; i < 8; i++)
printk("%04x ",
(unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(i << 5)));
printk("\n");
}
/*
* DMA transfer functions
*/
/*
* Enable a DMA channel. Also clear any error conditions.
*/
void vdma_enable(int channel)
{
int status;
if (vdma_debug)
printk("vdma_enable: channel %d\n", channel);
/*
* Check error conditions first
*/
status = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
if (status & 0x400)
printk("VDMA: Channel %d: Address error!\n", channel);
if (status & 0x200)
printk("VDMA: Channel %d: Memory error!\n", channel);
/*
* Clear all interrupt flags
*/
r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(channel << 5)) | R4030_TC_INTR
| R4030_MEM_INTR | R4030_ADDR_INTR);
/*
* Enable the desired channel
*/
r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(channel << 5)) |
R4030_CHNL_ENABLE);
}
EXPORT_SYMBOL(vdma_enable);
/*
* Disable a DMA channel
*/
void vdma_disable(int channel)
{
if (vdma_debug) {
int status =
r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(channel << 5));
printk("vdma_disable: channel %d\n", channel);
printk("VDMA: channel %d status: %04x (%s) mode: "
"%02x addr: %06x count: %06x\n",
channel, status,
((status & 0x600) ? "ERROR" : "OK"),
(unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_MODE +
(channel << 5)),
(unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_ADDR +
(channel << 5)),
(unsigned) r4030_read_reg32(JAZZ_R4030_CHNL_COUNT +
(channel << 5)));
}
r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(channel << 5)) &
~R4030_CHNL_ENABLE);
/*
* After disabling a DMA channel a remote bus register should be
* read to ensure that the current DMA acknowledge cycle is completed.
*/
*((volatile unsigned int *) JAZZ_DUMMY_DEVICE);
}
EXPORT_SYMBOL(vdma_disable);
/*
* Set DMA mode. This function accepts the mode values used
* to set a PC-style DMA controller. For the SCSI and FDC
* channels, we also set the default modes each time we're
* called.
* NOTE: The FAST and BURST dma modes are supported by the
* R4030 Rev. 2 and PICA chipsets only. I leave them disabled
* for now.
*/
void vdma_set_mode(int channel, int mode)
{
if (vdma_debug)
printk("vdma_set_mode: channel %d, mode 0x%x\n", channel,
mode);
switch (channel) {
case JAZZ_SCSI_DMA: /* scsi */
r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
/* R4030_MODE_FAST | */
/* R4030_MODE_BURST | */
R4030_MODE_INTR_EN |
R4030_MODE_WIDTH_16 |
R4030_MODE_ATIME_80);
break;
case JAZZ_FLOPPY_DMA: /* floppy */
r4030_write_reg32(JAZZ_R4030_CHNL_MODE + (channel << 5),
/* R4030_MODE_FAST | */
/* R4030_MODE_BURST | */
R4030_MODE_INTR_EN |
R4030_MODE_WIDTH_8 |
R4030_MODE_ATIME_120);
break;
case JAZZ_AUDIOL_DMA:
case JAZZ_AUDIOR_DMA:
printk("VDMA: Audio DMA not supported yet.\n");
break;
default:
printk
("VDMA: vdma_set_mode() called with unsupported channel %d!\n",
channel);
}
switch (mode) {
case DMA_MODE_READ:
r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(channel << 5)) &
~R4030_CHNL_WRITE);
break;
case DMA_MODE_WRITE:
r4030_write_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5),
r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE +
(channel << 5)) |
R4030_CHNL_WRITE);
break;
default:
printk
("VDMA: vdma_set_mode() called with unknown dma mode 0x%x\n",
mode);
}
}
EXPORT_SYMBOL(vdma_set_mode);
/*
* Set Transfer Address
*/
void vdma_set_addr(int channel, long addr)
{
if (vdma_debug)
printk("vdma_set_addr: channel %d, addr %lx\n", channel,
addr);
r4030_write_reg32(JAZZ_R4030_CHNL_ADDR + (channel << 5), addr);
}
EXPORT_SYMBOL(vdma_set_addr);
/*
* Set Transfer Count
*/
void vdma_set_count(int channel, int count)
{
if (vdma_debug)
printk("vdma_set_count: channel %d, count %08x\n", channel,
(unsigned) count);
r4030_write_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5), count);
}
EXPORT_SYMBOL(vdma_set_count);
/*
* Get Residual
*/
int vdma_get_residue(int channel)
{
int residual;
residual = r4030_read_reg32(JAZZ_R4030_CHNL_COUNT + (channel << 5));
if (vdma_debug)
printk("vdma_get_residual: channel %d: residual=%d\n",
channel, residual);
return residual;
}
/*
* Get DMA channel enable register
*/
int vdma_get_enable(int channel)
{
int enable;
enable = r4030_read_reg32(JAZZ_R4030_CHNL_ENABLE + (channel << 5));
if (vdma_debug)
printk("vdma_get_enable: channel %d: enable=%d\n", channel,
enable);
return enable;
}
arch_initcall(vdma_init);