[PATCH] wbsd update
From: Pierre Ossman
Date: Wed Jan 19 2005 - 05:43:15 EST
This patch includes the latest changes to the wbsd driver.
Changelog:
* Proper usage of kunmap.
* Comment about hw bugs.
* Waits for data transfers to finish properly.
* Added module version info.
* FIFO bug fix for small reads.
* Optimised FIFO loop.
* DMA demand mode.
* IRQ race condition when sending commands fixed.
/Pierre
Index: linux/drivers/mmc/wbsd.c
===================================================================
--- linux/drivers/mmc/wbsd.c (revision 105)
+++ linux/drivers/mmc/wbsd.c (working copy)
@@ -1,11 +1,24 @@
/*
- * linux/drivers/mmc/wbsd.c
+ * linux/drivers/mmc/wbsd.c - Winbond W83L51xD SD/MMC driver
*
- * Copyright (C) 2004 Pierre Ossman, All Rights Reserved.
+ * Copyright (C) 2004-2005 Pierre Ossman, All Rights Reserved.
*
* 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.
+ *
+ *
+ * Warning!
+ *
+ * Changes to the FIFO system should be done with extreme care since
+ * the hardware is full of bugs related to the FIFO. Known issues are:
+ *
+ * - FIFO size field in FSR is always zero.
+ *
+ * - FIFO interrupts tend not to work as they should. Interrupts are
+ * triggered only for full/empty events, not for threshold values.
+ *
+ * - On APIC systems the FIFO empty interrupt is sometimes lost.
*/
#include <linux/config.h>
@@ -27,7 +40,7 @@
#include "wbsd.h"
#define DRIVER_NAME "wbsd"
-#define DRIVER_VERSION "1.0"
+#define DRIVER_VERSION "1.1"
#ifdef CONFIG_MMC_DEBUG
#define DBG(x...) \
@@ -239,13 +252,14 @@
static inline char* wbsd_kmap_sg(struct wbsd_host* host)
{
- return kmap_atomic(host->cur_sg->page, KM_BIO_SRC_IRQ) +
+ host->mapped_sg = kmap_atomic(host->cur_sg->page, KM_BIO_SRC_IRQ) +
host->cur_sg->offset;
+ return host->mapped_sg;
}
static inline void wbsd_kunmap_sg(struct wbsd_host* host)
{
- kunmap_atomic(host->cur_sg->page, KM_BIO_SRC_IRQ);
+ kunmap_atomic(host->mapped_sg, KM_BIO_SRC_IRQ);
}
static inline void wbsd_sg_to_dma(struct wbsd_host* host, struct mmc_data* data)
@@ -272,7 +286,7 @@
memcpy(dmabuf, sgbuf, size);
else
memcpy(dmabuf, sgbuf, sg[i].length);
- kunmap_atomic(sg[i].page, KM_BIO_SRC_IRQ);
+ kunmap_atomic(sgbuf, KM_BIO_SRC_IRQ);
dmabuf += sg[i].length;
if (size < sg[i].length)
@@ -318,7 +332,7 @@
memcpy(sgbuf, dmabuf, size);
else
memcpy(sgbuf, dmabuf, sg[i].length);
- kunmap_atomic(sg[i].page, KM_BIO_SRC_IRQ);
+ kunmap_atomic(sgbuf, KM_BIO_SRC_IRQ);
dmabuf += sg[i].length;
if (size < sg[i].length)
@@ -400,16 +414,16 @@
static void wbsd_send_command(struct wbsd_host* host, struct mmc_command* cmd)
{
int i;
- u8 status, eir, isr;
+ u8 status, isr;
DBGF("Sending cmd (%x)\n", cmd->opcode);
/*
- * Disable interrupts as the interrupt routine
- * will destroy the contents of ISR.
+ * Clear accumulated ISR. The interrupt routine
+ * will fill this one with events that occur during
+ * transfer.
*/
- eir = inb(host->base + WBSD_EIR);
- outb(0, host->base + WBSD_EIR);
+ host->isr = 0;
/*
* Send the command (CRC calculated by host).
@@ -435,7 +449,7 @@
/*
* Read back status.
*/
- isr = inb(host->base + WBSD_ISR);
+ isr = host->isr;
/* Card removed? */
if (isr & WBSD_INT_CARD)
@@ -456,17 +470,6 @@
}
}
- /*
- * Restore interrupt mask to previous value.
- */
- outb(eir, host->base + WBSD_EIR);
-
- /*
- * Call the interrupt routine to jump start
- * interrupts.
- */
- wbsd_irq(0, host, NULL);
-
DBGF("Sent cmd (%x), res %d\n", cmd->opcode, cmd->error);
}
@@ -478,6 +481,7 @@
{
struct mmc_data* data = host->mrq->cmd->data;
char* buffer;
+ int i, fsr, fifo;
/*
* Handle excessive data.
@@ -491,60 +495,83 @@
* Drain the fifo. This has a tendency to loop longer
* than the FIFO length (usually one block).
*/
- while (!(inb(host->base + WBSD_FSR) & WBSD_FIFO_EMPTY))
+ while (!((fsr = inb(host->base + WBSD_FSR)) & WBSD_FIFO_EMPTY))
{
- *buffer = inb(host->base + WBSD_DFR);
- buffer++;
- host->offset++;
- host->remain--;
-
- data->bytes_xfered++;
-
/*
- * Transfer done?
- */
- if (data->bytes_xfered == host->size)
- {
- wbsd_kunmap_sg(host);
- return;
- }
+ * The size field in the FSR is broken so we have to
+ * do some guessing.
+ */
+ if (fsr & WBSD_FIFO_FULL)
+ fifo = 16;
+ else if (fsr & WBSD_FIFO_FUTHRE)
+ fifo = 8;
+ else
+ fifo = 1;
- /*
- * End of scatter list entry?
- */
- if (host->remain == 0)
+ for (i = 0;i < fifo;i++)
{
- wbsd_kunmap_sg(host);
+ *buffer = inb(host->base + WBSD_DFR);
+ buffer++;
+ host->offset++;
+ host->remain--;
+
+ data->bytes_xfered++;
/*
- * Get next entry. Check if last.
+ * Transfer done?
*/
- if (!wbsd_next_sg(host))
+ if (data->bytes_xfered == host->size)
{
+ wbsd_kunmap_sg(host);
+ return;
+ }
+
+ /*
+ * End of scatter list entry?
+ */
+ if (host->remain == 0)
+ {
+ wbsd_kunmap_sg(host);
+
/*
- * We should never reach this point.
- * It means that we're trying to
- * transfer more blocks than can fit
- * into the scatter list.
+ * Get next entry. Check if last.
*/
- BUG_ON(1);
+ if (!wbsd_next_sg(host))
+ {
+ /*
+ * We should never reach this point.
+ * It means that we're trying to
+ * transfer more blocks than can fit
+ * into the scatter list.
+ */
+ BUG_ON(1);
+
+ host->size = data->bytes_xfered;
+
+ return;
+ }
- host->size = data->bytes_xfered;
-
- return;
+ buffer = wbsd_kmap_sg(host);
}
-
- buffer = wbsd_kmap_sg(host);
}
}
wbsd_kunmap_sg(host);
+
+ /*
+ * This is a very dirty hack to solve a
+ * hardware problem. The chip doesn't trigger
+ * FIFO threshold interrupts properly.
+ */
+ if ((host->size - data->bytes_xfered) < 16)
+ tasklet_schedule(&host->fifo_tasklet);
}
static void wbsd_fill_fifo(struct wbsd_host* host)
{
struct mmc_data* data = host->mrq->cmd->data;
char* buffer;
+ int i, fsr, fifo;
/*
* Check that we aren't being called after the
@@ -559,50 +586,64 @@
* Fill the fifo. This has a tendency to loop longer
* than the FIFO length (usually one block).
*/
- while (!(inb(host->base + WBSD_FSR) & WBSD_FIFO_FULL))
+ while (!((fsr = inb(host->base + WBSD_FSR)) & WBSD_FIFO_FULL))
{
- outb(*buffer, host->base + WBSD_DFR);
- buffer++;
- host->offset++;
- host->remain--;
-
- data->bytes_xfered++;
-
/*
- * Transfer done?
- */
- if (data->bytes_xfered == host->size)
- {
- wbsd_kunmap_sg(host);
- return;
- }
+ * The size field in the FSR is broken so we have to
+ * do some guessing.
+ */
+ if (fsr & WBSD_FIFO_EMPTY)
+ fifo = 0;
+ else if (fsr & WBSD_FIFO_EMTHRE)
+ fifo = 8;
+ else
+ fifo = 15;
- /*
- * End of scatter list entry?
- */
- if (host->remain == 0)
+ for (i = 16;i > fifo;i--)
{
- wbsd_kunmap_sg(host);
+ outb(*buffer, host->base + WBSD_DFR);
+ buffer++;
+ host->offset++;
+ host->remain--;
+ data->bytes_xfered++;
+
/*
- * Get next entry. Check if last.
+ * Transfer done?
*/
- if (!wbsd_next_sg(host))
+ if (data->bytes_xfered == host->size)
{
+ wbsd_kunmap_sg(host);
+ return;
+ }
+
+ /*
+ * End of scatter list entry?
+ */
+ if (host->remain == 0)
+ {
+ wbsd_kunmap_sg(host);
+
/*
- * We should never reach this point.
- * It means that we're trying to
- * transfer more blocks than can fit
- * into the scatter list.
+ * Get next entry. Check if last.
*/
- BUG_ON(1);
+ if (!wbsd_next_sg(host))
+ {
+ /*
+ * We should never reach this point.
+ * It means that we're trying to
+ * transfer more blocks than can fit
+ * into the scatter list.
+ */
+ BUG_ON(1);
+
+ host->size = data->bytes_xfered;
+
+ return;
+ }
- host->size = data->bytes_xfered;
-
- return;
+ buffer = wbsd_kmap_sg(host);
}
-
- buffer = wbsd_kmap_sg(host);
}
}
@@ -689,9 +730,9 @@
disable_dma(host->dma);
clear_dma_ff(host->dma);
if (data->flags & MMC_DATA_READ)
- set_dma_mode(host->dma, DMA_MODE_READ);
+ set_dma_mode(host->dma, DMA_MODE_READ & ~0x40);
else
- set_dma_mode(host->dma, DMA_MODE_WRITE);
+ set_dma_mode(host->dma, DMA_MODE_WRITE & ~0x40);
set_dma_addr(host->dma, host->dma_addr);
set_dma_count(host->dma, host->size);
@@ -701,8 +742,7 @@
/*
* Enable DMA on the host.
*/
- wbsd_write_index(host, WBSD_IDX_DMA,
- WBSD_DMA_SINGLE | WBSD_DMA_ENABLE);
+ wbsd_write_index(host, WBSD_IDX_DMA, WBSD_DMA_ENABLE);
}
else
{
@@ -746,6 +786,7 @@
{
unsigned long dmaflags;
int count;
+ u8 status;
WARN_ON(host->mrq == NULL);
@@ -754,6 +795,15 @@
*/
if (data->stop)
wbsd_send_command(host, data->stop);
+
+ /*
+ * Wait for the controller to leave data
+ * transfer state.
+ */
+ do
+ {
+ status = wbsd_read_index(host, WBSD_IDX_STATUS);
+ } while (status & (WBSD_BLOCK_READ | WBSD_BLOCK_WRITE));
/*
* DMA transfer?
@@ -851,7 +901,13 @@
* transfered.
*/
if (cmd->data && (cmd->error == MMC_ERR_NONE))
- {
+ {
+ /*
+ * Dirty fix for hardware bug.
+ */
+ if (host->dma == -1)
+ tasklet_schedule(&host->fifo_tasklet);
+
spin_unlock_bh(&host->lock);
return;
@@ -1021,7 +1077,6 @@
spin_lock(&host->lock);
- WARN_ON(!host->mrq);
if (!host->mrq)
goto end;
@@ -1046,7 +1101,6 @@
spin_lock(&host->lock);
- WARN_ON(!host->mrq);
if (!host->mrq)
goto end;
@@ -1126,6 +1180,8 @@
*/
if (isr == 0xff || isr == 0x00)
return IRQ_NONE;
+
+ host->isr |= isr;
/*
* Schedule tasklets as needed.
@@ -1133,7 +1189,7 @@
if (isr & WBSD_INT_CARD)
tasklet_schedule(&host->card_tasklet);
if (isr & WBSD_INT_FIFO_THRE)
- tasklet_hi_schedule(&host->fifo_tasklet);
+ tasklet_schedule(&host->fifo_tasklet);
if (isr & WBSD_INT_CRC)
tasklet_hi_schedule(&host->crc_tasklet);
if (isr & WBSD_INT_TIMEOUT)
@@ -1392,8 +1448,8 @@
* Maximum number of segments. Worst case is one sector per segment
* so this will be 64kB/512.
*/
- mmc->max_hw_segs = NR_SG;
- mmc->max_phys_segs = NR_SG;
+ mmc->max_hw_segs = 128;
+ mmc->max_phys_segs = 128;
/*
* Maximum number of sectors in one transfer. Also limited by 64kB
@@ -1590,6 +1646,7 @@
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Winbond W83L51xD SD/MMC card interface driver");
+MODULE_VERSION(DRIVER_VERSION);
MODULE_PARM_DESC(io, "I/O base to allocate. Must be 8 byte aligned. (default 0x248)");
MODULE_PARM_DESC(irq, "IRQ to allocate. (default 6)");
Index: linux/drivers/mmc/wbsd.h
===================================================================
--- linux/drivers/mmc/wbsd.h (revision 105)
+++ linux/drivers/mmc/wbsd.h (working copy)
@@ -1,7 +1,7 @@
/*
- * linux/drivers/mmc/wbsd.h
+ * linux/drivers/mmc/wbsd.h - Winbond W83L51xD SD/MMC driver
*
- * Copyright (C) 2004 Pierre Ossman, All Rights Reserved.
+ * Copyright (C) 2004-2005 Pierre Ossman, All Rights Reserved.
*
* 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
@@ -119,6 +119,8 @@
#define WBSD_FIFOEN_FULL 0x10
#define WBSD_FIFO_THREMASK 0x0F
+#define WBSD_BLOCK_READ 0x80
+#define WBSD_BLOCK_WRITE 0x40
#define WBSD_BUSY 0x20
#define WBSD_CARDTRAFFIC 0x04
#define WBSD_SENDCMD 0x02
@@ -132,9 +134,6 @@
#define WBSD_CRC_FAIL 0x0B /* S101E (01011) */
-/* 64kB / 512 */
-#define NR_SG 128
-
struct wbsd_host
{
struct mmc_host* mmc; /* MMC structure */
@@ -143,9 +142,11 @@
struct mmc_request* mrq; /* Current request */
- struct scatterlist sg[NR_SG]; /* SG list */
+ u8 isr; /* Accumulated ISR */
+
struct scatterlist* cur_sg; /* Current SG entry */
unsigned int num_sg; /* Number of entries left */
+ void* mapped_sg; /* vaddr of mapped sg */
unsigned int offset; /* Offset into current entry */
unsigned int remain; /* Data left in curren entry */