/*
- * File: arch/blackfin/kernel/bfin_dma_5xx.c
- * Based on:
- * Author:
+ * bfin_dma_5xx.c - Blackfin DMA implementation
*
- * Created:
- * Description: This file contains the simple DMA Implementation for Blackfin
- *
- * Modified:
- * Copyright 2004-2006 Analog Devices Inc.
- *
- * Bugs: Enter bugs at http://blackfin.uclinux.org/
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see the file COPYING, or write
- * to the Free Software Foundation, Inc.,
- * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ * Copyright 2004-2006 Analog Devices Inc.
+ * Licensed under the GPL-2 or later.
*/
#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/param.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
-#include <linux/interrupt.h>
-#include <linux/kernel.h>
-#include <linux/param.h>
+#include <linux/spinlock.h>
#include <asm/blackfin.h>
-#include <asm/dma.h>
#include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/uaccess.h>
/**************************************************************************
* Global Variables
arch_initcall(blackfin_dma_init);
#ifdef CONFIG_PROC_FS
-
static int proc_dma_show(struct seq_file *m, void *v)
{
int i;
- for (i = 0 ; i < MAX_DMA_CHANNELS; ++i)
+ for (i = 0; i < MAX_DMA_CHANNELS; ++i)
if (dma_ch[i].chan_status != DMA_CHANNEL_FREE)
seq_printf(m, "%2d: %s\n", i, dma_ch[i].device_id);
}
#endif
-static void *__dma_memcpy(void *dest, const void *src, size_t size)
+/**
+ * blackfin_dma_early_init - minimal DMA init
+ *
+ * Setup a few DMA registers so we can safely do DMA transfers early on in
+ * the kernel booting process. Really this just means using dma_memcpy().
+ */
+void __init blackfin_dma_early_init(void)
{
- int direction; /* 1 - address decrease, 0 - address increase */
- int flag_align; /* 1 - address aligned, 0 - address unaligned */
- int flag_2D; /* 1 - 2D DMA needed, 0 - 1D DMA needed */
- unsigned long flags;
-
- if (size <= 0)
- return NULL;
-
- local_irq_save(flags);
-
- if ((unsigned long)src < memory_end)
- blackfin_dcache_flush_range((unsigned int)src,
- (unsigned int)(src + size));
-
- if ((unsigned long)dest < memory_end)
- blackfin_dcache_invalidate_range((unsigned int)dest,
- (unsigned int)(dest + size));
-
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- if ((unsigned long)src < (unsigned long)dest)
- direction = 1;
- else
- direction = 0;
-
- if ((((unsigned long)dest % 2) == 0) && (((unsigned long)src % 2) == 0)
- && ((size % 2) == 0))
- flag_align = 1;
- else
- flag_align = 0;
-
- if (size > 0x10000) /* size > 64K */
- flag_2D = 1;
- else
- flag_2D = 0;
-
- /* Setup destination and source start address */
- if (direction) {
- if (flag_align) {
- bfin_write_MDMA_D0_START_ADDR(dest + size - 2);
- bfin_write_MDMA_S0_START_ADDR(src + size - 2);
- } else {
- bfin_write_MDMA_D0_START_ADDR(dest + size - 1);
- bfin_write_MDMA_S0_START_ADDR(src + size - 1);
- }
- } else {
- bfin_write_MDMA_D0_START_ADDR(dest);
- bfin_write_MDMA_S0_START_ADDR(src);
- }
-
- /* Setup destination and source xcount */
- if (flag_2D) {
- if (flag_align) {
- bfin_write_MDMA_D0_X_COUNT(1024 / 2);
- bfin_write_MDMA_S0_X_COUNT(1024 / 2);
- } else {
- bfin_write_MDMA_D0_X_COUNT(1024);
- bfin_write_MDMA_S0_X_COUNT(1024);
- }
- bfin_write_MDMA_D0_Y_COUNT(size >> 10);
- bfin_write_MDMA_S0_Y_COUNT(size >> 10);
- } else {
- if (flag_align) {
- bfin_write_MDMA_D0_X_COUNT(size / 2);
- bfin_write_MDMA_S0_X_COUNT(size / 2);
- } else {
- bfin_write_MDMA_D0_X_COUNT(size);
- bfin_write_MDMA_S0_X_COUNT(size);
- }
- }
-
- /* Setup destination and source xmodify and ymodify */
- if (direction) {
- if (flag_align) {
- bfin_write_MDMA_D0_X_MODIFY(-2);
- bfin_write_MDMA_S0_X_MODIFY(-2);
- if (flag_2D) {
- bfin_write_MDMA_D0_Y_MODIFY(-2);
- bfin_write_MDMA_S0_Y_MODIFY(-2);
- }
- } else {
- bfin_write_MDMA_D0_X_MODIFY(-1);
- bfin_write_MDMA_S0_X_MODIFY(-1);
- if (flag_2D) {
- bfin_write_MDMA_D0_Y_MODIFY(-1);
- bfin_write_MDMA_S0_Y_MODIFY(-1);
- }
- }
- } else {
- if (flag_align) {
- bfin_write_MDMA_D0_X_MODIFY(2);
- bfin_write_MDMA_S0_X_MODIFY(2);
- if (flag_2D) {
- bfin_write_MDMA_D0_Y_MODIFY(2);
- bfin_write_MDMA_S0_Y_MODIFY(2);
- }
- } else {
- bfin_write_MDMA_D0_X_MODIFY(1);
- bfin_write_MDMA_S0_X_MODIFY(1);
- if (flag_2D) {
- bfin_write_MDMA_D0_Y_MODIFY(1);
- bfin_write_MDMA_S0_Y_MODIFY(1);
- }
- }
- }
-
- /* Enable source DMA */
- if (flag_2D) {
- if (flag_align) {
- bfin_write_MDMA_S0_CONFIG(DMAEN | DMA2D | WDSIZE_16);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | DMA2D | WDSIZE_16);
- } else {
- bfin_write_MDMA_S0_CONFIG(DMAEN | DMA2D);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | DMA2D);
- }
- } else {
- if (flag_align) {
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_16);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_16);
- } else {
- bfin_write_MDMA_S0_CONFIG(DMAEN);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN);
- }
- }
-
- SSYNC();
-
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE))
- ;
-
- bfin_write_MDMA_D0_IRQ_STATUS(bfin_read_MDMA_D0_IRQ_STATUS() |
- (DMA_DONE | DMA_ERR));
-
bfin_write_MDMA_S0_CONFIG(0);
- bfin_write_MDMA_D0_CONFIG(0);
-
- local_irq_restore(flags);
-
- return dest;
}
-void *dma_memcpy(void *dest, const void *src, size_t size)
-{
- size_t bulk;
- size_t rest;
- void * addr;
-
- bulk = (size >> 16) << 16;
- rest = size - bulk;
- if (bulk)
- __dma_memcpy(dest, src, bulk);
- __dma_memcpy(dest+bulk, src+bulk, rest);
- return dest;
-}
-EXPORT_SYMBOL(dma_memcpy);
-
/**
- * safe_dma_memcpy - DMA memcpy w/argument checking
+ * __dma_memcpy - program the MDMA registers
*
- * Verify arguments are safe before heading to dma_memcpy().
+ * Actually program MDMA0 and wait for the transfer to finish. Disable IRQs
+ * while programming registers so that everything is fully configured. Wait
+ * for DMA to finish with IRQs enabled. If interrupted, the initial DMA_DONE
+ * check will make sure we don't clobber any existing transfer.
*/
-void *safe_dma_memcpy(void *dest, const void *src, size_t size)
-{
- if (!access_ok(VERIFY_WRITE, dst, size))
- return NULL;
- if (!access_ok(VERIFY_READ, src, size))
- return NULL;
- return dma_memcpy(dst, src, size);
-}
-EXPORT_SYMBOL(safe_dma_memcpy);
-
-void dma_outsb(unsigned long addr, const void *buf, unsigned short len)
+static void __dma_memcpy(u32 daddr, s16 dmod, u32 saddr, s16 smod, size_t cnt, u32 conf)
{
+ static DEFINE_SPINLOCK(mdma_lock);
unsigned long flags;
- local_irq_save(flags);
-
- blackfin_dcache_flush_range((unsigned int)buf,
- (unsigned int)(buf) + len);
+ spin_lock_irqsave(&mdma_lock, flags);
+
+ if (bfin_read_MDMA_S0_CONFIG())
+ while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE))
+ continue;
+
+ if (conf & DMA2D) {
+ /* For larger bit sizes, we've already divided down cnt so it
+ * is no longer a multiple of 64k. So we have to break down
+ * the limit here so it is a multiple of the incoming size.
+ * There is no limitation here in terms of total size other
+ * than the hardware though as the bits lost in the shift are
+ * made up by MODIFY (== we can hit the whole address space).
+ * X: (2^(16 - 0)) * 1 == (2^(16 - 1)) * 2 == (2^(16 - 2)) * 4
+ */
+ u32 shift = abs(dmod) >> 1;
+ size_t ycnt = cnt >> (16 - shift);
+ cnt = 1 << (16 - shift);
+ bfin_write_MDMA_D0_Y_COUNT(ycnt);
+ bfin_write_MDMA_S0_Y_COUNT(ycnt);
+ bfin_write_MDMA_D0_Y_MODIFY(dmod);
+ bfin_write_MDMA_S0_Y_MODIFY(smod);
+ }
- bfin_write_MDMA_D0_START_ADDR(addr);
- bfin_write_MDMA_D0_X_COUNT(len);
- bfin_write_MDMA_D0_X_MODIFY(0);
+ bfin_write_MDMA_D0_START_ADDR(daddr);
+ bfin_write_MDMA_D0_X_COUNT(cnt);
+ bfin_write_MDMA_D0_X_MODIFY(dmod);
bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
- bfin_write_MDMA_S0_START_ADDR(buf);
- bfin_write_MDMA_S0_X_COUNT(len);
- bfin_write_MDMA_S0_X_MODIFY(1);
+ bfin_write_MDMA_S0_START_ADDR(saddr);
+ bfin_write_MDMA_S0_X_COUNT(cnt);
+ bfin_write_MDMA_S0_X_MODIFY(smod);
bfin_write_MDMA_S0_IRQ_STATUS(DMA_DONE | DMA_ERR);
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_8);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_8);
+ bfin_write_MDMA_S0_CONFIG(DMAEN | conf);
+ bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | conf);
+
+ spin_unlock_irqrestore(&mdma_lock, flags);
SSYNC();
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE));
+ while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE))
+ if (bfin_read_MDMA_S0_CONFIG())
+ continue;
+ else
+ return;
bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
bfin_write_MDMA_S0_CONFIG(0);
bfin_write_MDMA_D0_CONFIG(0);
- local_irq_restore(flags);
-
}
-EXPORT_SYMBOL(dma_outsb);
-
-void dma_insb(unsigned long addr, void *buf, unsigned short len)
+/**
+ * _dma_memcpy - translate C memcpy settings into MDMA settings
+ *
+ * Handle all the high level steps before we touch the MDMA registers. So
+ * handle caching, tweaking of sizes, and formatting of addresses.
+ */
+static void *_dma_memcpy(void *pdst, const void *psrc, size_t size)
{
- unsigned long flags;
+ u32 conf, shift;
+ s16 mod;
+ unsigned long dst = (unsigned long)pdst;
+ unsigned long src = (unsigned long)psrc;
- blackfin_dcache_invalidate_range((unsigned int)buf,
- (unsigned int)(buf) + len);
+ if (size == 0)
+ return NULL;
- local_irq_save(flags);
- bfin_write_MDMA_D0_START_ADDR(buf);
- bfin_write_MDMA_D0_X_COUNT(len);
- bfin_write_MDMA_D0_X_MODIFY(1);
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
+ if (bfin_addr_dcachable(src))
+ blackfin_dcache_flush_range(src, src + size);
- bfin_write_MDMA_S0_START_ADDR(addr);
- bfin_write_MDMA_S0_X_COUNT(len);
- bfin_write_MDMA_S0_X_MODIFY(0);
- bfin_write_MDMA_S0_IRQ_STATUS(DMA_DONE | DMA_ERR);
+ if (bfin_addr_dcachable(dst))
+ blackfin_dcache_invalidate_range(dst, dst + size);
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_8);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_8);
-
- SSYNC();
+ if (dst % 4 == 0 && src % 4 == 0 && size % 4 == 0) {
+ conf = WDSIZE_32;
+ shift = 2;
+ } else if (dst % 2 == 0 && src % 2 == 0 && size % 2 == 0) {
+ conf = WDSIZE_16;
+ shift = 1;
+ } else {
+ conf = WDSIZE_8;
+ shift = 0;
+ }
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE));
+ /* If the two memory regions have a chance of overlapping, make
+ * sure the memcpy still works as expected. Do this by having the
+ * copy run backwards instead.
+ */
+ mod = 1 << shift;
+ if (src < dst) {
+ mod *= -1;
+ dst += size + mod;
+ src += size + mod;
+ }
+ size >>= shift;
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
+ if (size > 0x10000)
+ conf |= DMA2D;
- bfin_write_MDMA_S0_CONFIG(0);
- bfin_write_MDMA_D0_CONFIG(0);
- local_irq_restore(flags);
+ __dma_memcpy(dst, mod, src, mod, size, conf);
+ return pdst;
}
-EXPORT_SYMBOL(dma_insb);
-void dma_outsw(unsigned long addr, const void *buf, unsigned short len)
+/**
+ * dma_memcpy - DMA memcpy under mutex lock
+ *
+ * Do not check arguments before starting the DMA memcpy. Break the transfer
+ * up into two pieces. The first transfer is in multiples of 64k and the
+ * second transfer is the piece smaller than 64k.
+ */
+void *dma_memcpy(void *dst, const void *src, size_t size)
{
- unsigned long flags;
-
- local_irq_save(flags);
-
- blackfin_dcache_flush_range((unsigned int)buf,
- (unsigned int)(buf) + len * sizeof(short));
-
- bfin_write_MDMA_D0_START_ADDR(addr);
- bfin_write_MDMA_D0_X_COUNT(len);
- bfin_write_MDMA_D0_X_MODIFY(0);
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_START_ADDR(buf);
- bfin_write_MDMA_S0_X_COUNT(len);
- bfin_write_MDMA_S0_X_MODIFY(2);
- bfin_write_MDMA_S0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_16);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_16);
-
- SSYNC();
-
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE));
-
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(0);
- bfin_write_MDMA_D0_CONFIG(0);
- local_irq_restore(flags);
-
+ size_t bulk, rest;
+ bulk = size & ~0xffff;
+ rest = size - bulk;
+ if (bulk)
+ _dma_memcpy(dst, src, bulk);
+ _dma_memcpy(dst + bulk, src + bulk, rest);
+ return dst;
}
-EXPORT_SYMBOL(dma_outsw);
+EXPORT_SYMBOL(dma_memcpy);
-void dma_insw(unsigned long addr, void *buf, unsigned short len)
+/**
+ * safe_dma_memcpy - DMA memcpy w/argument checking
+ *
+ * Verify arguments are safe before heading to dma_memcpy().
+ */
+void *safe_dma_memcpy(void *dst, const void *src, size_t size)
{
- unsigned long flags;
-
- blackfin_dcache_invalidate_range((unsigned int)buf,
- (unsigned int)(buf) + len * sizeof(short));
-
- local_irq_save(flags);
-
- bfin_write_MDMA_D0_START_ADDR(buf);
- bfin_write_MDMA_D0_X_COUNT(len);
- bfin_write_MDMA_D0_X_MODIFY(2);
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_START_ADDR(addr);
- bfin_write_MDMA_S0_X_COUNT(len);
- bfin_write_MDMA_S0_X_MODIFY(0);
- bfin_write_MDMA_S0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_16);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_16);
-
- SSYNC();
-
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE));
-
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(0);
- bfin_write_MDMA_D0_CONFIG(0);
- local_irq_restore(flags);
-
+ if (!access_ok(VERIFY_WRITE, dst, size))
+ return NULL;
+ if (!access_ok(VERIFY_READ, src, size))
+ return NULL;
+ return dma_memcpy(dst, src, size);
}
-EXPORT_SYMBOL(dma_insw);
+EXPORT_SYMBOL(safe_dma_memcpy);
-void dma_outsl(unsigned long addr, const void *buf, unsigned short len)
+static void _dma_out(unsigned long addr, unsigned long buf, unsigned short len,
+ u16 size, u16 dma_size)
{
- unsigned long flags;
-
- local_irq_save(flags);
-
- blackfin_dcache_flush_range((unsigned int)buf,
- (unsigned int)(buf) + len * sizeof(long));
-
- bfin_write_MDMA_D0_START_ADDR(addr);
- bfin_write_MDMA_D0_X_COUNT(len);
- bfin_write_MDMA_D0_X_MODIFY(0);
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_START_ADDR(buf);
- bfin_write_MDMA_S0_X_COUNT(len);
- bfin_write_MDMA_S0_X_MODIFY(4);
- bfin_write_MDMA_S0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_32);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_32);
-
- SSYNC();
-
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE));
-
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(0);
- bfin_write_MDMA_D0_CONFIG(0);
- local_irq_restore(flags);
-
+ blackfin_dcache_flush_range(buf, buf + len * size);
+ __dma_memcpy(addr, 0, buf, size, len, dma_size);
}
-EXPORT_SYMBOL(dma_outsl);
-void dma_insl(unsigned long addr, void *buf, unsigned short len)
+static void _dma_in(unsigned long addr, unsigned long buf, unsigned short len,
+ u16 size, u16 dma_size)
{
- unsigned long flags;
-
- blackfin_dcache_invalidate_range((unsigned int)buf,
- (unsigned int)(buf) + len * sizeof(long));
-
- local_irq_save(flags);
-
- bfin_write_MDMA_D0_START_ADDR(buf);
- bfin_write_MDMA_D0_X_COUNT(len);
- bfin_write_MDMA_D0_X_MODIFY(4);
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_START_ADDR(addr);
- bfin_write_MDMA_S0_X_COUNT(len);
- bfin_write_MDMA_S0_X_MODIFY(0);
- bfin_write_MDMA_S0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(DMAEN | WDSIZE_32);
- bfin_write_MDMA_D0_CONFIG(WNR | DI_EN | DMAEN | WDSIZE_32);
-
- SSYNC();
-
- while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE));
-
- bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
-
- bfin_write_MDMA_S0_CONFIG(0);
- bfin_write_MDMA_D0_CONFIG(0);
- local_irq_restore(flags);
-
+ blackfin_dcache_invalidate_range(buf, buf + len * size);
+ __dma_memcpy(buf, size, addr, 0, len, dma_size);
}
-EXPORT_SYMBOL(dma_insl);
+
+#define MAKE_DMA_IO(io, bwl, isize, dmasize, cnst) \
+void dma_##io##s##bwl(unsigned long addr, cnst void *buf, unsigned short len) \
+{ \
+ _dma_##io(addr, (unsigned long)buf, len, isize, WDSIZE_##dmasize); \
+} \
+EXPORT_SYMBOL(dma_##io##s##bwl)
+MAKE_DMA_IO(out, b, 1, 8, const);
+MAKE_DMA_IO(in, b, 1, 8, );
+MAKE_DMA_IO(out, w, 2, 16, const);
+MAKE_DMA_IO(in, w, 2, 16, );
+MAKE_DMA_IO(out, l, 4, 32, const);
+MAKE_DMA_IO(in, l, 4, 32, );
projects / kernel / kernel-generic.git / commitdiff