[PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with DMA

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* [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with DMA
@ 2010-11-23 16:24 ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

While testing SDIO on SuperH with TMIO and DMA, it turned out, that 
buffers, submitted to the driver can be arbitrarily aligned, and this is 
not handled by the tmio driver. This patch series fixes this issue.

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with DMA
@ 2010-11-23 16:24 ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

While testing SDIO on SuperH with TMIO and DMA, it turned out, that 
buffers, submitted to the driver can be arbitrarily aligned, and this is 
not handled by the tmio driver. This patch series fixes this issue.

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* [PATCH 1/3] mmc: tmio: merge the private header into the driver
  2010-11-23 16:24 ` Guennadi Liakhovetski
@ 2010-11-23 16:24   ` Guennadi Liakhovetski
  -1 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

drivers/mmc/host/tmio_mmc.h is only used by drivers/mmc/host/tmio_mmc.c, this
needlessly complicates source-code handling.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mmc/host/tmio_mmc.c |  215 ++++++++++++++++++++++++++++++++++++++++-
 drivers/mmc/host/tmio_mmc.h |  226 -------------------------------------------
 2 files changed, 210 insertions(+), 231 deletions(-)
 delete mode 100644 drivers/mmc/host/tmio_mmc.h

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 10416c3..118ad86 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -25,16 +25,221 @@
  *   double buffer support
  *
  */
-#include <linux/module.h>
-#include <linux/irq.h>
-#include <linux/device.h>
+
 #include <linux/delay.h>
+#include <linux/device.h>
 #include <linux/dmaengine.h>
-#include <linux/mmc/host.h>
+#include <linux/highmem.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/tmio.h>
+#include <linux/mmc/host.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/scatterlist.h>
+
+#define CTL_SD_CMD 0x00
+#define CTL_ARG_REG 0x04
+#define CTL_STOP_INTERNAL_ACTION 0x08
+#define CTL_XFER_BLK_COUNT 0xa
+#define CTL_RESPONSE 0x0c
+#define CTL_STATUS 0x1c
+#define CTL_IRQ_MASK 0x20
+#define CTL_SD_CARD_CLK_CTL 0x24
+#define CTL_SD_XFER_LEN 0x26
+#define CTL_SD_MEM_CARD_OPT 0x28
+#define CTL_SD_ERROR_DETAIL_STATUS 0x2c
+#define CTL_SD_DATA_PORT 0x30
+#define CTL_TRANSACTION_CTL 0x34
+#define CTL_RESET_SD 0xe0
+#define CTL_SDIO_REGS 0x100
+#define CTL_CLK_AND_WAIT_CTL 0x138
+#define CTL_RESET_SDIO 0x1e0
+
+/* Definitions for values the CTRL_STATUS register can take. */
+#define TMIO_STAT_CMDRESPEND    0x00000001
+#define TMIO_STAT_DATAEND       0x00000004
+#define TMIO_STAT_CARD_REMOVE   0x00000008
+#define TMIO_STAT_CARD_INSERT   0x00000010
+#define TMIO_STAT_SIGSTATE      0x00000020
+#define TMIO_STAT_WRPROTECT     0x00000080
+#define TMIO_STAT_CARD_REMOVE_A 0x00000100
+#define TMIO_STAT_CARD_INSERT_A 0x00000200
+#define TMIO_STAT_SIGSTATE_A    0x00000400
+#define TMIO_STAT_CMD_IDX_ERR   0x00010000
+#define TMIO_STAT_CRCFAIL       0x00020000
+#define TMIO_STAT_STOPBIT_ERR   0x00040000
+#define TMIO_STAT_DATATIMEOUT   0x00080000
+#define TMIO_STAT_RXOVERFLOW    0x00100000
+#define TMIO_STAT_TXUNDERRUN    0x00200000
+#define TMIO_STAT_CMDTIMEOUT    0x00400000
+#define TMIO_STAT_RXRDY         0x01000000
+#define TMIO_STAT_TXRQ          0x02000000
+#define TMIO_STAT_ILL_FUNC      0x20000000
+#define TMIO_STAT_CMD_BUSY      0x40000000
+#define TMIO_STAT_ILL_ACCESS    0x80000000
+
+/* Define some IRQ masks */
+/* This is the mask used at reset by the chip */
+#define TMIO_MASK_ALL           0x837f031d
+#define TMIO_MASK_READOP  (TMIO_STAT_RXRDY | TMIO_STAT_DATAEND)
+#define TMIO_MASK_WRITEOP (TMIO_STAT_TXRQ | TMIO_STAT_DATAEND)
+#define TMIO_MASK_CMD     (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT | \
+		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
+#define TMIO_MASK_IRQ     (TMIO_MASK_READOP | TMIO_MASK_WRITEOP | TMIO_MASK_CMD)
+
+#define enable_mmc_irqs(host, i) \
+	do { \
+		u32 mask;\
+		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
+		mask &= ~((i) & TMIO_MASK_IRQ); \
+		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
+	} while (0)
+
+#define disable_mmc_irqs(host, i) \
+	do { \
+		u32 mask;\
+		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
+		mask |= ((i) & TMIO_MASK_IRQ); \
+		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
+	} while (0)
+
+#define ack_mmc_irqs(host, i) \
+	do { \
+		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
+	} while (0)
+
+
+struct tmio_mmc_host {
+	void __iomem *ctl;
+	unsigned long bus_shift;
+	struct mmc_command      *cmd;
+	struct mmc_request      *mrq;
+	struct mmc_data         *data;
+	struct mmc_host         *mmc;
+	int                     irq;
+
+	/* Callbacks for clock / power control */
+	void (*set_pwr)(struct platform_device *host, int state);
+	void (*set_clk_div)(struct platform_device *host, int state);
+
+	/* pio related stuff */
+	struct scatterlist      *sg_ptr;
+	unsigned int            sg_len;
+	unsigned int            sg_off;
+
+	struct platform_device *pdev;
+
+	/* DMA support */
+	struct dma_chan		*chan_rx;
+	struct dma_chan		*chan_tx;
+	struct tasklet_struct	dma_complete;
+	struct tasklet_struct	dma_issue;
+#ifdef CONFIG_TMIO_MMC_DMA
+	unsigned int            dma_sglen;
+#endif
+};
 
-#include "tmio_mmc.h"
+static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
+{
+	return readw(host->ctl + (addr << host->bus_shift));
+}
+
+static void sd_ctrl_read16_rep(struct tmio_mmc_host *host, int addr,
+		u16 *buf, int count)
+{
+	readsw(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static u32 sd_ctrl_read32(struct tmio_mmc_host *host, int addr)
+{
+	return readw(host->ctl + (addr << host->bus_shift)) |
+	       readw(host->ctl + ((addr + 2) << host->bus_shift)) << 16;
+}
+
+static void sd_ctrl_write16(struct tmio_mmc_host *host, int addr, u16 val)
+{
+	writew(val, host->ctl + (addr << host->bus_shift));
+}
+
+static void sd_ctrl_write16_rep(struct tmio_mmc_host *host, int addr,
+		u16 *buf, int count)
+{
+	writesw(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static void sd_ctrl_write32(struct tmio_mmc_host *host, int addr, u32 val)
+{
+	writew(val, host->ctl + (addr << host->bus_shift));
+	writew(val >> 16, host->ctl + ((addr + 2) << host->bus_shift));
+}
+
+static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
+{
+	host->sg_len = data->sg_len;
+	host->sg_ptr = data->sg;
+	host->sg_off = 0;
+}
+
+static int tmio_mmc_next_sg(struct tmio_mmc_host *host)
+{
+	host->sg_ptr = sg_next(host->sg_ptr);
+	host->sg_off = 0;
+	return --host->sg_len;
+}
+
+static char *tmio_mmc_kmap_atomic(struct scatterlist *sg, unsigned long *flags)
+{
+	local_irq_save(*flags);
+	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
+}
+
+static void tmio_mmc_kunmap_atomic(void *virt, unsigned long *flags)
+{
+	kunmap_atomic(virt, KM_BIO_SRC_IRQ);
+	local_irq_restore(*flags);
+}
+
+#ifdef CONFIG_MMC_DEBUG
+
+#define STATUS_TO_TEXT(a) \
+	do { \
+		if (status & TMIO_STAT_##a) \
+			printk(#a); \
+	} while (0)
+
+void pr_debug_status(u32 status)
+{
+	printk(KERN_DEBUG "status: %08x = ", status);
+	STATUS_TO_TEXT(CARD_REMOVE);
+	STATUS_TO_TEXT(CARD_INSERT);
+	STATUS_TO_TEXT(SIGSTATE);
+	STATUS_TO_TEXT(WRPROTECT);
+	STATUS_TO_TEXT(CARD_REMOVE_A);
+	STATUS_TO_TEXT(CARD_INSERT_A);
+	STATUS_TO_TEXT(SIGSTATE_A);
+	STATUS_TO_TEXT(CMD_IDX_ERR);
+	STATUS_TO_TEXT(STOPBIT_ERR);
+	STATUS_TO_TEXT(ILL_FUNC);
+	STATUS_TO_TEXT(CMD_BUSY);
+	STATUS_TO_TEXT(CMDRESPEND);
+	STATUS_TO_TEXT(DATAEND);
+	STATUS_TO_TEXT(CRCFAIL);
+	STATUS_TO_TEXT(DATATIMEOUT);
+	STATUS_TO_TEXT(CMDTIMEOUT);
+	STATUS_TO_TEXT(RXOVERFLOW);
+	STATUS_TO_TEXT(TXUNDERRUN);
+	STATUS_TO_TEXT(RXRDY);
+	STATUS_TO_TEXT(TXRQ);
+	STATUS_TO_TEXT(ILL_ACCESS);
+	printk("\n");
+}
+
+#else
+#define pr_debug_status(s)  do { } while (0)
+#endif
 
 static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
 {
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
deleted file mode 100644
index 0b7d916..0000000
--- a/drivers/mmc/host/tmio_mmc.h
+++ /dev/null
@@ -1,226 +0,0 @@
-/* Definitons for use with the tmio_mmc.c
- *
- * (c) 2004 Ian Molton <spyro@f2s.com>
- * (c) 2007 Ian Molton <spyro@f2s.com>
- *
- * 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.
- *
- */
-
-#include <linux/highmem.h>
-#include <linux/interrupt.h>
-#include <linux/dmaengine.h>
-
-#define CTL_SD_CMD 0x00
-#define CTL_ARG_REG 0x04
-#define CTL_STOP_INTERNAL_ACTION 0x08
-#define CTL_XFER_BLK_COUNT 0xa
-#define CTL_RESPONSE 0x0c
-#define CTL_STATUS 0x1c
-#define CTL_IRQ_MASK 0x20
-#define CTL_SD_CARD_CLK_CTL 0x24
-#define CTL_SD_XFER_LEN 0x26
-#define CTL_SD_MEM_CARD_OPT 0x28
-#define CTL_SD_ERROR_DETAIL_STATUS 0x2c
-#define CTL_SD_DATA_PORT 0x30
-#define CTL_TRANSACTION_CTL 0x34
-#define CTL_RESET_SD 0xe0
-#define CTL_SDIO_REGS 0x100
-#define CTL_CLK_AND_WAIT_CTL 0x138
-#define CTL_RESET_SDIO 0x1e0
-
-/* Definitions for values the CTRL_STATUS register can take. */
-#define TMIO_STAT_CMDRESPEND    0x00000001
-#define TMIO_STAT_DATAEND       0x00000004
-#define TMIO_STAT_CARD_REMOVE   0x00000008
-#define TMIO_STAT_CARD_INSERT   0x00000010
-#define TMIO_STAT_SIGSTATE      0x00000020
-#define TMIO_STAT_WRPROTECT     0x00000080
-#define TMIO_STAT_CARD_REMOVE_A 0x00000100
-#define TMIO_STAT_CARD_INSERT_A 0x00000200
-#define TMIO_STAT_SIGSTATE_A    0x00000400
-#define TMIO_STAT_CMD_IDX_ERR   0x00010000
-#define TMIO_STAT_CRCFAIL       0x00020000
-#define TMIO_STAT_STOPBIT_ERR   0x00040000
-#define TMIO_STAT_DATATIMEOUT   0x00080000
-#define TMIO_STAT_RXOVERFLOW    0x00100000
-#define TMIO_STAT_TXUNDERRUN    0x00200000
-#define TMIO_STAT_CMDTIMEOUT    0x00400000
-#define TMIO_STAT_RXRDY         0x01000000
-#define TMIO_STAT_TXRQ          0x02000000
-#define TMIO_STAT_ILL_FUNC      0x20000000
-#define TMIO_STAT_CMD_BUSY      0x40000000
-#define TMIO_STAT_ILL_ACCESS    0x80000000
-
-/* Define some IRQ masks */
-/* This is the mask used at reset by the chip */
-#define TMIO_MASK_ALL           0x837f031d
-#define TMIO_MASK_READOP  (TMIO_STAT_RXRDY | TMIO_STAT_DATAEND)
-#define TMIO_MASK_WRITEOP (TMIO_STAT_TXRQ | TMIO_STAT_DATAEND)
-#define TMIO_MASK_CMD     (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT | \
-		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
-#define TMIO_MASK_IRQ     (TMIO_MASK_READOP | TMIO_MASK_WRITEOP | TMIO_MASK_CMD)
-
-
-#define enable_mmc_irqs(host, i) \
-	do { \
-		u32 mask;\
-		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
-		mask &= ~((i) & TMIO_MASK_IRQ); \
-		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
-	} while (0)
-
-#define disable_mmc_irqs(host, i) \
-	do { \
-		u32 mask;\
-		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
-		mask |= ((i) & TMIO_MASK_IRQ); \
-		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
-	} while (0)
-
-#define ack_mmc_irqs(host, i) \
-	do { \
-		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
-	} while (0)
-
-
-struct tmio_mmc_host {
-	void __iomem *ctl;
-	unsigned long bus_shift;
-	struct mmc_command      *cmd;
-	struct mmc_request      *mrq;
-	struct mmc_data         *data;
-	struct mmc_host         *mmc;
-	int                     irq;
-
-	/* Callbacks for clock / power control */
-	void (*set_pwr)(struct platform_device *host, int state);
-	void (*set_clk_div)(struct platform_device *host, int state);
-
-	/* pio related stuff */
-	struct scatterlist      *sg_ptr;
-	unsigned int            sg_len;
-	unsigned int            sg_off;
-
-	struct platform_device *pdev;
-
-	/* DMA support */
-	struct dma_chan		*chan_rx;
-	struct dma_chan		*chan_tx;
-	struct tasklet_struct	dma_complete;
-	struct tasklet_struct	dma_issue;
-#ifdef CONFIG_TMIO_MMC_DMA
-	unsigned int            dma_sglen;
-#endif
-};
-
-#include <linux/io.h>
-
-static inline u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
-{
-	return readw(host->ctl + (addr << host->bus_shift));
-}
-
-static inline void sd_ctrl_read16_rep(struct tmio_mmc_host *host, int addr,
-		u16 *buf, int count)
-{
-	readsw(host->ctl + (addr << host->bus_shift), buf, count);
-}
-
-static inline u32 sd_ctrl_read32(struct tmio_mmc_host *host, int addr)
-{
-	return readw(host->ctl + (addr << host->bus_shift)) |
-	       readw(host->ctl + ((addr + 2) << host->bus_shift)) << 16;
-}
-
-static inline void sd_ctrl_write16(struct tmio_mmc_host *host, int addr,
-		u16 val)
-{
-	writew(val, host->ctl + (addr << host->bus_shift));
-}
-
-static inline void sd_ctrl_write16_rep(struct tmio_mmc_host *host, int addr,
-		u16 *buf, int count)
-{
-	writesw(host->ctl + (addr << host->bus_shift), buf, count);
-}
-
-static inline void sd_ctrl_write32(struct tmio_mmc_host *host, int addr,
-		u32 val)
-{
-	writew(val, host->ctl + (addr << host->bus_shift));
-	writew(val >> 16, host->ctl + ((addr + 2) << host->bus_shift));
-}
-
-#include <linux/scatterlist.h>
-#include <linux/blkdev.h>
-
-static inline void tmio_mmc_init_sg(struct tmio_mmc_host *host,
-	struct mmc_data *data)
-{
-	host->sg_len = data->sg_len;
-	host->sg_ptr = data->sg;
-	host->sg_off = 0;
-}
-
-static inline int tmio_mmc_next_sg(struct tmio_mmc_host *host)
-{
-	host->sg_ptr = sg_next(host->sg_ptr);
-	host->sg_off = 0;
-	return --host->sg_len;
-}
-
-static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg,
-	unsigned long *flags)
-{
-	local_irq_save(*flags);
-	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
-}
-
-static inline void tmio_mmc_kunmap_atomic(void *virt,
-	unsigned long *flags)
-{
-	kunmap_atomic(virt, KM_BIO_SRC_IRQ);
-	local_irq_restore(*flags);
-}
-
-#ifdef CONFIG_MMC_DEBUG
-
-#define STATUS_TO_TEXT(a) \
-	do { \
-		if (status & TMIO_STAT_##a) \
-			printk(#a); \
-	} while (0)
-
-void pr_debug_status(u32 status)
-{
-	printk(KERN_DEBUG "status: %08x = ", status);
-	STATUS_TO_TEXT(CARD_REMOVE);
-	STATUS_TO_TEXT(CARD_INSERT);
-	STATUS_TO_TEXT(SIGSTATE);
-	STATUS_TO_TEXT(WRPROTECT);
-	STATUS_TO_TEXT(CARD_REMOVE_A);
-	STATUS_TO_TEXT(CARD_INSERT_A);
-	STATUS_TO_TEXT(SIGSTATE_A);
-	STATUS_TO_TEXT(CMD_IDX_ERR);
-	STATUS_TO_TEXT(STOPBIT_ERR);
-	STATUS_TO_TEXT(ILL_FUNC);
-	STATUS_TO_TEXT(CMD_BUSY);
-	STATUS_TO_TEXT(CMDRESPEND);
-	STATUS_TO_TEXT(DATAEND);
-	STATUS_TO_TEXT(CRCFAIL);
-	STATUS_TO_TEXT(DATATIMEOUT);
-	STATUS_TO_TEXT(CMDTIMEOUT);
-	STATUS_TO_TEXT(RXOVERFLOW);
-	STATUS_TO_TEXT(TXUNDERRUN);
-	STATUS_TO_TEXT(RXRDY);
-	STATUS_TO_TEXT(TXRQ);
-	STATUS_TO_TEXT(ILL_ACCESS);
-	printk("\n");
-}
-
-#else
-#define pr_debug_status(s)  do { } while (0)
-#endif
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 1/3] mmc: tmio: merge the private header into the driver
@ 2010-11-23 16:24   ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

drivers/mmc/host/tmio_mmc.h is only used by drivers/mmc/host/tmio_mmc.c, this
needlessly complicates source-code handling.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mmc/host/tmio_mmc.c |  215 ++++++++++++++++++++++++++++++++++++++++-
 drivers/mmc/host/tmio_mmc.h |  226 -------------------------------------------
 2 files changed, 210 insertions(+), 231 deletions(-)
 delete mode 100644 drivers/mmc/host/tmio_mmc.h

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 10416c3..118ad86 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -25,16 +25,221 @@
  *   double buffer support
  *
  */
-#include <linux/module.h>
-#include <linux/irq.h>
-#include <linux/device.h>
+
 #include <linux/delay.h>
+#include <linux/device.h>
 #include <linux/dmaengine.h>
-#include <linux/mmc/host.h>
+#include <linux/highmem.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/tmio.h>
+#include <linux/mmc/host.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/scatterlist.h>
+
+#define CTL_SD_CMD 0x00
+#define CTL_ARG_REG 0x04
+#define CTL_STOP_INTERNAL_ACTION 0x08
+#define CTL_XFER_BLK_COUNT 0xa
+#define CTL_RESPONSE 0x0c
+#define CTL_STATUS 0x1c
+#define CTL_IRQ_MASK 0x20
+#define CTL_SD_CARD_CLK_CTL 0x24
+#define CTL_SD_XFER_LEN 0x26
+#define CTL_SD_MEM_CARD_OPT 0x28
+#define CTL_SD_ERROR_DETAIL_STATUS 0x2c
+#define CTL_SD_DATA_PORT 0x30
+#define CTL_TRANSACTION_CTL 0x34
+#define CTL_RESET_SD 0xe0
+#define CTL_SDIO_REGS 0x100
+#define CTL_CLK_AND_WAIT_CTL 0x138
+#define CTL_RESET_SDIO 0x1e0
+
+/* Definitions for values the CTRL_STATUS register can take. */
+#define TMIO_STAT_CMDRESPEND    0x00000001
+#define TMIO_STAT_DATAEND       0x00000004
+#define TMIO_STAT_CARD_REMOVE   0x00000008
+#define TMIO_STAT_CARD_INSERT   0x00000010
+#define TMIO_STAT_SIGSTATE      0x00000020
+#define TMIO_STAT_WRPROTECT     0x00000080
+#define TMIO_STAT_CARD_REMOVE_A 0x00000100
+#define TMIO_STAT_CARD_INSERT_A 0x00000200
+#define TMIO_STAT_SIGSTATE_A    0x00000400
+#define TMIO_STAT_CMD_IDX_ERR   0x00010000
+#define TMIO_STAT_CRCFAIL       0x00020000
+#define TMIO_STAT_STOPBIT_ERR   0x00040000
+#define TMIO_STAT_DATATIMEOUT   0x00080000
+#define TMIO_STAT_RXOVERFLOW    0x00100000
+#define TMIO_STAT_TXUNDERRUN    0x00200000
+#define TMIO_STAT_CMDTIMEOUT    0x00400000
+#define TMIO_STAT_RXRDY         0x01000000
+#define TMIO_STAT_TXRQ          0x02000000
+#define TMIO_STAT_ILL_FUNC      0x20000000
+#define TMIO_STAT_CMD_BUSY      0x40000000
+#define TMIO_STAT_ILL_ACCESS    0x80000000
+
+/* Define some IRQ masks */
+/* This is the mask used at reset by the chip */
+#define TMIO_MASK_ALL           0x837f031d
+#define TMIO_MASK_READOP  (TMIO_STAT_RXRDY | TMIO_STAT_DATAEND)
+#define TMIO_MASK_WRITEOP (TMIO_STAT_TXRQ | TMIO_STAT_DATAEND)
+#define TMIO_MASK_CMD     (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT | \
+		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
+#define TMIO_MASK_IRQ     (TMIO_MASK_READOP | TMIO_MASK_WRITEOP | TMIO_MASK_CMD)
+
+#define enable_mmc_irqs(host, i) \
+	do { \
+		u32 mask;\
+		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
+		mask &= ~((i) & TMIO_MASK_IRQ); \
+		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
+	} while (0)
+
+#define disable_mmc_irqs(host, i) \
+	do { \
+		u32 mask;\
+		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
+		mask |= ((i) & TMIO_MASK_IRQ); \
+		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
+	} while (0)
+
+#define ack_mmc_irqs(host, i) \
+	do { \
+		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
+	} while (0)
+
+
+struct tmio_mmc_host {
+	void __iomem *ctl;
+	unsigned long bus_shift;
+	struct mmc_command      *cmd;
+	struct mmc_request      *mrq;
+	struct mmc_data         *data;
+	struct mmc_host         *mmc;
+	int                     irq;
+
+	/* Callbacks for clock / power control */
+	void (*set_pwr)(struct platform_device *host, int state);
+	void (*set_clk_div)(struct platform_device *host, int state);
+
+	/* pio related stuff */
+	struct scatterlist      *sg_ptr;
+	unsigned int            sg_len;
+	unsigned int            sg_off;
+
+	struct platform_device *pdev;
+
+	/* DMA support */
+	struct dma_chan		*chan_rx;
+	struct dma_chan		*chan_tx;
+	struct tasklet_struct	dma_complete;
+	struct tasklet_struct	dma_issue;
+#ifdef CONFIG_TMIO_MMC_DMA
+	unsigned int            dma_sglen;
+#endif
+};
 
-#include "tmio_mmc.h"
+static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
+{
+	return readw(host->ctl + (addr << host->bus_shift));
+}
+
+static void sd_ctrl_read16_rep(struct tmio_mmc_host *host, int addr,
+		u16 *buf, int count)
+{
+	readsw(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static u32 sd_ctrl_read32(struct tmio_mmc_host *host, int addr)
+{
+	return readw(host->ctl + (addr << host->bus_shift)) |
+	       readw(host->ctl + ((addr + 2) << host->bus_shift)) << 16;
+}
+
+static void sd_ctrl_write16(struct tmio_mmc_host *host, int addr, u16 val)
+{
+	writew(val, host->ctl + (addr << host->bus_shift));
+}
+
+static void sd_ctrl_write16_rep(struct tmio_mmc_host *host, int addr,
+		u16 *buf, int count)
+{
+	writesw(host->ctl + (addr << host->bus_shift), buf, count);
+}
+
+static void sd_ctrl_write32(struct tmio_mmc_host *host, int addr, u32 val)
+{
+	writew(val, host->ctl + (addr << host->bus_shift));
+	writew(val >> 16, host->ctl + ((addr + 2) << host->bus_shift));
+}
+
+static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
+{
+	host->sg_len = data->sg_len;
+	host->sg_ptr = data->sg;
+	host->sg_off = 0;
+}
+
+static int tmio_mmc_next_sg(struct tmio_mmc_host *host)
+{
+	host->sg_ptr = sg_next(host->sg_ptr);
+	host->sg_off = 0;
+	return --host->sg_len;
+}
+
+static char *tmio_mmc_kmap_atomic(struct scatterlist *sg, unsigned long *flags)
+{
+	local_irq_save(*flags);
+	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
+}
+
+static void tmio_mmc_kunmap_atomic(void *virt, unsigned long *flags)
+{
+	kunmap_atomic(virt, KM_BIO_SRC_IRQ);
+	local_irq_restore(*flags);
+}
+
+#ifdef CONFIG_MMC_DEBUG
+
+#define STATUS_TO_TEXT(a) \
+	do { \
+		if (status & TMIO_STAT_##a) \
+			printk(#a); \
+	} while (0)
+
+void pr_debug_status(u32 status)
+{
+	printk(KERN_DEBUG "status: %08x = ", status);
+	STATUS_TO_TEXT(CARD_REMOVE);
+	STATUS_TO_TEXT(CARD_INSERT);
+	STATUS_TO_TEXT(SIGSTATE);
+	STATUS_TO_TEXT(WRPROTECT);
+	STATUS_TO_TEXT(CARD_REMOVE_A);
+	STATUS_TO_TEXT(CARD_INSERT_A);
+	STATUS_TO_TEXT(SIGSTATE_A);
+	STATUS_TO_TEXT(CMD_IDX_ERR);
+	STATUS_TO_TEXT(STOPBIT_ERR);
+	STATUS_TO_TEXT(ILL_FUNC);
+	STATUS_TO_TEXT(CMD_BUSY);
+	STATUS_TO_TEXT(CMDRESPEND);
+	STATUS_TO_TEXT(DATAEND);
+	STATUS_TO_TEXT(CRCFAIL);
+	STATUS_TO_TEXT(DATATIMEOUT);
+	STATUS_TO_TEXT(CMDTIMEOUT);
+	STATUS_TO_TEXT(RXOVERFLOW);
+	STATUS_TO_TEXT(TXUNDERRUN);
+	STATUS_TO_TEXT(RXRDY);
+	STATUS_TO_TEXT(TXRQ);
+	STATUS_TO_TEXT(ILL_ACCESS);
+	printk("\n");
+}
+
+#else
+#define pr_debug_status(s)  do { } while (0)
+#endif
 
 static void tmio_mmc_set_clock(struct tmio_mmc_host *host, int new_clock)
 {
diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h
deleted file mode 100644
index 0b7d916..0000000
--- a/drivers/mmc/host/tmio_mmc.h
+++ /dev/null
@@ -1,226 +0,0 @@
-/* Definitons for use with the tmio_mmc.c
- *
- * (c) 2004 Ian Molton <spyro@f2s.com>
- * (c) 2007 Ian Molton <spyro@f2s.com>
- *
- * 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.
- *
- */
-
-#include <linux/highmem.h>
-#include <linux/interrupt.h>
-#include <linux/dmaengine.h>
-
-#define CTL_SD_CMD 0x00
-#define CTL_ARG_REG 0x04
-#define CTL_STOP_INTERNAL_ACTION 0x08
-#define CTL_XFER_BLK_COUNT 0xa
-#define CTL_RESPONSE 0x0c
-#define CTL_STATUS 0x1c
-#define CTL_IRQ_MASK 0x20
-#define CTL_SD_CARD_CLK_CTL 0x24
-#define CTL_SD_XFER_LEN 0x26
-#define CTL_SD_MEM_CARD_OPT 0x28
-#define CTL_SD_ERROR_DETAIL_STATUS 0x2c
-#define CTL_SD_DATA_PORT 0x30
-#define CTL_TRANSACTION_CTL 0x34
-#define CTL_RESET_SD 0xe0
-#define CTL_SDIO_REGS 0x100
-#define CTL_CLK_AND_WAIT_CTL 0x138
-#define CTL_RESET_SDIO 0x1e0
-
-/* Definitions for values the CTRL_STATUS register can take. */
-#define TMIO_STAT_CMDRESPEND    0x00000001
-#define TMIO_STAT_DATAEND       0x00000004
-#define TMIO_STAT_CARD_REMOVE   0x00000008
-#define TMIO_STAT_CARD_INSERT   0x00000010
-#define TMIO_STAT_SIGSTATE      0x00000020
-#define TMIO_STAT_WRPROTECT     0x00000080
-#define TMIO_STAT_CARD_REMOVE_A 0x00000100
-#define TMIO_STAT_CARD_INSERT_A 0x00000200
-#define TMIO_STAT_SIGSTATE_A    0x00000400
-#define TMIO_STAT_CMD_IDX_ERR   0x00010000
-#define TMIO_STAT_CRCFAIL       0x00020000
-#define TMIO_STAT_STOPBIT_ERR   0x00040000
-#define TMIO_STAT_DATATIMEOUT   0x00080000
-#define TMIO_STAT_RXOVERFLOW    0x00100000
-#define TMIO_STAT_TXUNDERRUN    0x00200000
-#define TMIO_STAT_CMDTIMEOUT    0x00400000
-#define TMIO_STAT_RXRDY         0x01000000
-#define TMIO_STAT_TXRQ          0x02000000
-#define TMIO_STAT_ILL_FUNC      0x20000000
-#define TMIO_STAT_CMD_BUSY      0x40000000
-#define TMIO_STAT_ILL_ACCESS    0x80000000
-
-/* Define some IRQ masks */
-/* This is the mask used at reset by the chip */
-#define TMIO_MASK_ALL           0x837f031d
-#define TMIO_MASK_READOP  (TMIO_STAT_RXRDY | TMIO_STAT_DATAEND)
-#define TMIO_MASK_WRITEOP (TMIO_STAT_TXRQ | TMIO_STAT_DATAEND)
-#define TMIO_MASK_CMD     (TMIO_STAT_CMDRESPEND | TMIO_STAT_CMDTIMEOUT | \
-		TMIO_STAT_CARD_REMOVE | TMIO_STAT_CARD_INSERT)
-#define TMIO_MASK_IRQ     (TMIO_MASK_READOP | TMIO_MASK_WRITEOP | TMIO_MASK_CMD)
-
-
-#define enable_mmc_irqs(host, i) \
-	do { \
-		u32 mask;\
-		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
-		mask &= ~((i) & TMIO_MASK_IRQ); \
-		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
-	} while (0)
-
-#define disable_mmc_irqs(host, i) \
-	do { \
-		u32 mask;\
-		mask  = sd_ctrl_read32((host), CTL_IRQ_MASK); \
-		mask |= ((i) & TMIO_MASK_IRQ); \
-		sd_ctrl_write32((host), CTL_IRQ_MASK, mask); \
-	} while (0)
-
-#define ack_mmc_irqs(host, i) \
-	do { \
-		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
-	} while (0)
-
-
-struct tmio_mmc_host {
-	void __iomem *ctl;
-	unsigned long bus_shift;
-	struct mmc_command      *cmd;
-	struct mmc_request      *mrq;
-	struct mmc_data         *data;
-	struct mmc_host         *mmc;
-	int                     irq;
-
-	/* Callbacks for clock / power control */
-	void (*set_pwr)(struct platform_device *host, int state);
-	void (*set_clk_div)(struct platform_device *host, int state);
-
-	/* pio related stuff */
-	struct scatterlist      *sg_ptr;
-	unsigned int            sg_len;
-	unsigned int            sg_off;
-
-	struct platform_device *pdev;
-
-	/* DMA support */
-	struct dma_chan		*chan_rx;
-	struct dma_chan		*chan_tx;
-	struct tasklet_struct	dma_complete;
-	struct tasklet_struct	dma_issue;
-#ifdef CONFIG_TMIO_MMC_DMA
-	unsigned int            dma_sglen;
-#endif
-};
-
-#include <linux/io.h>
-
-static inline u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
-{
-	return readw(host->ctl + (addr << host->bus_shift));
-}
-
-static inline void sd_ctrl_read16_rep(struct tmio_mmc_host *host, int addr,
-		u16 *buf, int count)
-{
-	readsw(host->ctl + (addr << host->bus_shift), buf, count);
-}
-
-static inline u32 sd_ctrl_read32(struct tmio_mmc_host *host, int addr)
-{
-	return readw(host->ctl + (addr << host->bus_shift)) |
-	       readw(host->ctl + ((addr + 2) << host->bus_shift)) << 16;
-}
-
-static inline void sd_ctrl_write16(struct tmio_mmc_host *host, int addr,
-		u16 val)
-{
-	writew(val, host->ctl + (addr << host->bus_shift));
-}
-
-static inline void sd_ctrl_write16_rep(struct tmio_mmc_host *host, int addr,
-		u16 *buf, int count)
-{
-	writesw(host->ctl + (addr << host->bus_shift), buf, count);
-}
-
-static inline void sd_ctrl_write32(struct tmio_mmc_host *host, int addr,
-		u32 val)
-{
-	writew(val, host->ctl + (addr << host->bus_shift));
-	writew(val >> 16, host->ctl + ((addr + 2) << host->bus_shift));
-}
-
-#include <linux/scatterlist.h>
-#include <linux/blkdev.h>
-
-static inline void tmio_mmc_init_sg(struct tmio_mmc_host *host,
-	struct mmc_data *data)
-{
-	host->sg_len = data->sg_len;
-	host->sg_ptr = data->sg;
-	host->sg_off = 0;
-}
-
-static inline int tmio_mmc_next_sg(struct tmio_mmc_host *host)
-{
-	host->sg_ptr = sg_next(host->sg_ptr);
-	host->sg_off = 0;
-	return --host->sg_len;
-}
-
-static inline char *tmio_mmc_kmap_atomic(struct scatterlist *sg,
-	unsigned long *flags)
-{
-	local_irq_save(*flags);
-	return kmap_atomic(sg_page(sg), KM_BIO_SRC_IRQ) + sg->offset;
-}
-
-static inline void tmio_mmc_kunmap_atomic(void *virt,
-	unsigned long *flags)
-{
-	kunmap_atomic(virt, KM_BIO_SRC_IRQ);
-	local_irq_restore(*flags);
-}
-
-#ifdef CONFIG_MMC_DEBUG
-
-#define STATUS_TO_TEXT(a) \
-	do { \
-		if (status & TMIO_STAT_##a) \
-			printk(#a); \
-	} while (0)
-
-void pr_debug_status(u32 status)
-{
-	printk(KERN_DEBUG "status: %08x = ", status);
-	STATUS_TO_TEXT(CARD_REMOVE);
-	STATUS_TO_TEXT(CARD_INSERT);
-	STATUS_TO_TEXT(SIGSTATE);
-	STATUS_TO_TEXT(WRPROTECT);
-	STATUS_TO_TEXT(CARD_REMOVE_A);
-	STATUS_TO_TEXT(CARD_INSERT_A);
-	STATUS_TO_TEXT(SIGSTATE_A);
-	STATUS_TO_TEXT(CMD_IDX_ERR);
-	STATUS_TO_TEXT(STOPBIT_ERR);
-	STATUS_TO_TEXT(ILL_FUNC);
-	STATUS_TO_TEXT(CMD_BUSY);
-	STATUS_TO_TEXT(CMDRESPEND);
-	STATUS_TO_TEXT(DATAEND);
-	STATUS_TO_TEXT(CRCFAIL);
-	STATUS_TO_TEXT(DATATIMEOUT);
-	STATUS_TO_TEXT(CMDTIMEOUT);
-	STATUS_TO_TEXT(RXOVERFLOW);
-	STATUS_TO_TEXT(TXUNDERRUN);
-	STATUS_TO_TEXT(RXRDY);
-	STATUS_TO_TEXT(TXRQ);
-	STATUS_TO_TEXT(ILL_ACCESS);
-	printk("\n");
-}
-
-#else
-#define pr_debug_status(s)  do { } while (0)
-#endif
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA
  2010-11-23 16:24 ` Guennadi Liakhovetski
@ 2010-11-23 16:24   ` Guennadi Liakhovetski
  -1 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

For example, with SDIO WLAN cards, some transfers happen with buffers at odd
addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
This patch extends the tmio driver with a bounce buffer, that is used for
single entry scatter-gather lists both for sending and receiving. If we ever
encounter unaligned transfers with multi-element sg lists, this patch will have
to be extended. For now it just falls back to PIO in this and other unsupported
cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mmc/host/tmio_mmc.c |   81 +++++++++++++++++++++++++++++++++++++++----
 include/linux/mfd/tmio.h    |    1 +
 2 files changed, 75 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 118ad86..57ece9d 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -111,6 +111,8 @@
 		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
 	} while (0)
 
+/* This is arbitrary, just noone needed any higher alignment yet */
+#define MAX_ALIGN 4
 
 struct tmio_mmc_host {
 	void __iomem *ctl;
@@ -127,6 +129,7 @@ struct tmio_mmc_host {
 
 	/* pio related stuff */
 	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
 	unsigned int            sg_len;
 	unsigned int            sg_off;
 
@@ -139,6 +142,8 @@ struct tmio_mmc_host {
 	struct tasklet_struct	dma_issue;
 #ifdef CONFIG_TMIO_MMC_DMA
 	unsigned int            dma_sglen;
+	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
+	struct scatterlist	bounce_sg;
 #endif
 };
 
@@ -180,6 +185,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
 {
 	host->sg_len = data->sg_len;
 	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
 	host->sg_off = 0;
 }
 
@@ -436,8 +442,14 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 	 */
 
 	if (data->flags & MMC_DATA_READ) {
-		if (!host->chan_rx)
+		if (!host->chan_rx) {
 			disable_mmc_irqs(host, TMIO_MASK_READOP);
+		} else if (host->sg_ptr = &host->bounce_sg) {
+			unsigned long flags;
+			void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+			memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+			tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		}
 		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
 			host->mrq);
 	} else {
@@ -529,8 +541,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 			if (!host->chan_rx)
 				enable_mmc_irqs(host, TMIO_MASK_READOP);
 		} else {
-			struct dma_chan *chan = host->chan_tx;
-			if (!chan)
+			if (!host->chan_tx)
 				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 			else
 				tasklet_schedule(&host->dma_issue);
@@ -634,11 +645,36 @@ static void tmio_dma_complete(void *arg)
 
 static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_rx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 	if (ret > 0) {
@@ -661,6 +697,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -684,11 +721,40 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 
 static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_tx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
 	if (ret > 0) {
@@ -709,6 +775,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 085f041..dbfc053 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
 struct tmio_mmc_dma {
 	void *chan_priv_tx;
 	void *chan_priv_rx;
+	int alignment_shift;
 };
 
 /*
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2010-11-23 16:24   ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

For example, with SDIO WLAN cards, some transfers happen with buffers at odd
addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
This patch extends the tmio driver with a bounce buffer, that is used for
single entry scatter-gather lists both for sending and receiving. If we ever
encounter unaligned transfers with multi-element sg lists, this patch will have
to be extended. For now it just falls back to PIO in this and other unsupported
cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mmc/host/tmio_mmc.c |   81 +++++++++++++++++++++++++++++++++++++++----
 include/linux/mfd/tmio.h    |    1 +
 2 files changed, 75 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 118ad86..57ece9d 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -111,6 +111,8 @@
 		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
 	} while (0)
 
+/* This is arbitrary, just noone needed any higher alignment yet */
+#define MAX_ALIGN 4
 
 struct tmio_mmc_host {
 	void __iomem *ctl;
@@ -127,6 +129,7 @@ struct tmio_mmc_host {
 
 	/* pio related stuff */
 	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
 	unsigned int            sg_len;
 	unsigned int            sg_off;
 
@@ -139,6 +142,8 @@ struct tmio_mmc_host {
 	struct tasklet_struct	dma_issue;
 #ifdef CONFIG_TMIO_MMC_DMA
 	unsigned int            dma_sglen;
+	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
+	struct scatterlist	bounce_sg;
 #endif
 };
 
@@ -180,6 +185,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
 {
 	host->sg_len = data->sg_len;
 	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
 	host->sg_off = 0;
 }
 
@@ -436,8 +442,14 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 	 */
 
 	if (data->flags & MMC_DATA_READ) {
-		if (!host->chan_rx)
+		if (!host->chan_rx) {
 			disable_mmc_irqs(host, TMIO_MASK_READOP);
+		} else if (host->sg_ptr == &host->bounce_sg) {
+			unsigned long flags;
+			void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+			memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+			tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		}
 		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
 			host->mrq);
 	} else {
@@ -529,8 +541,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 			if (!host->chan_rx)
 				enable_mmc_irqs(host, TMIO_MASK_READOP);
 		} else {
-			struct dma_chan *chan = host->chan_tx;
-			if (!chan)
+			if (!host->chan_tx)
 				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 			else
 				tasklet_schedule(&host->dma_issue);
@@ -634,11 +645,36 @@ static void tmio_dma_complete(void *arg)
 
 static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_rx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 	if (ret > 0) {
@@ -661,6 +697,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -684,11 +721,40 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 
 static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_tx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
 	if (ret > 0) {
@@ -709,6 +775,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 085f041..dbfc053 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
 struct tmio_mmc_dma {
 	void *chan_priv_tx;
 	void *chan_priv_rx;
+	int alignment_shift;
 };
 
 /*
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned
  2010-11-23 16:24 ` Guennadi Liakhovetski
@ 2010-11-23 16:24   ` Guennadi Liakhovetski
  -1 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

The SDHI controller on SH-Mobile SoCs requires even buffer addresses, when used
with DMA.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mfd/sh_mobile_sdhi.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
index f1714f9..3ca20ec 100644
--- a/drivers/mfd/sh_mobile_sdhi.c
+++ b/drivers/mfd/sh_mobile_sdhi.c
@@ -136,6 +136,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
 		priv->param_rx.slave_id = p->dma_slave_rx;
 		priv->dma_priv.chan_priv_tx = &priv->param_tx;
 		priv->dma_priv.chan_priv_rx = &priv->param_rx;
+		priv->dma_priv.alignment_shift = 1; /* 2-byte alignment */
 		mmc_data->dma = &priv->dma_priv;
 	}
 
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers
@ 2010-11-23 16:24   ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-11-23 16:24 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

The SDHI controller on SH-Mobile SoCs requires even buffer addresses, when used
with DMA.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
 drivers/mfd/sh_mobile_sdhi.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
index f1714f9..3ca20ec 100644
--- a/drivers/mfd/sh_mobile_sdhi.c
+++ b/drivers/mfd/sh_mobile_sdhi.c
@@ -136,6 +136,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
 		priv->param_rx.slave_id = p->dma_slave_rx;
 		priv->dma_priv.chan_priv_tx = &priv->param_tx;
 		priv->dma_priv.chan_priv_rx = &priv->param_rx;
+		priv->dma_priv.alignment_shift = 1; /* 2-byte alignment */
 		mmc_data->dma = &priv->dma_priv;
 	}
 
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned
  2010-11-23 16:24   ` Guennadi Liakhovetski
@ 2010-11-26 12:04     ` Samuel Ortiz
  -1 siblings, 0 replies; 31+ messages in thread
From: Samuel Ortiz @ 2010-11-26 12:04 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton

Hi Guennadi,

On Tue, Nov 23, 2010 at 05:24:15PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at odd
> addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
> This patch extends the tmio driver with a bounce buffer, that is used for
> single entry scatter-gather lists both for sending and receiving. If we ever
> encounter unaligned transfers with multi-element sg lists, this patch will have
> to be extended. For now it just falls back to PIO in this and other unsupported
> cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
I'm not sure about who is going to carry those patches, probably not me
though.
So, for the MFD part:
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

Cheers,
Samuel.

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2010-11-26 12:04     ` Samuel Ortiz
  0 siblings, 0 replies; 31+ messages in thread
From: Samuel Ortiz @ 2010-11-26 12:04 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton

Hi Guennadi,

On Tue, Nov 23, 2010 at 05:24:15PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at odd
> addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
> This patch extends the tmio driver with a bounce buffer, that is used for
> single entry scatter-gather lists both for sending and receiving. If we ever
> encounter unaligned transfers with multi-element sg lists, this patch will have
> to be extended. For now it just falls back to PIO in this and other unsupported
> cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
I'm not sure about who is going to carry those patches, probably not me
though.
So, for the MFD part:
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

Cheers,
Samuel.

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce
  2010-11-23 16:24   ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers Guennadi Liakhovetski
@ 2010-11-26 12:05     ` Samuel Ortiz
  -1 siblings, 0 replies; 31+ messages in thread
From: Samuel Ortiz @ 2010-11-26 12:05 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton

On Tue, Nov 23, 2010 at 05:24:19PM +0100, Guennadi Liakhovetski wrote:
> The SDHI controller on SH-Mobile SoCs requires even buffer addresses, when used
> with DMA.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

Cheers,
Samuel.

> ---
>  drivers/mfd/sh_mobile_sdhi.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
> index f1714f9..3ca20ec 100644
> --- a/drivers/mfd/sh_mobile_sdhi.c
> +++ b/drivers/mfd/sh_mobile_sdhi.c
> @@ -136,6 +136,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
>  		priv->param_rx.slave_id = p->dma_slave_rx;
>  		priv->dma_priv.chan_priv_tx = &priv->param_tx;
>  		priv->dma_priv.chan_priv_rx = &priv->param_rx;
> +		priv->dma_priv.alignment_shift = 1; /* 2-byte alignment */
>  		mmc_data->dma = &priv->dma_priv;
>  	}
>  
> -- 
> 1.7.2.3
> 

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers
@ 2010-11-26 12:05     ` Samuel Ortiz
  0 siblings, 0 replies; 31+ messages in thread
From: Samuel Ortiz @ 2010-11-26 12:05 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton

On Tue, Nov 23, 2010 at 05:24:19PM +0100, Guennadi Liakhovetski wrote:
> The SDHI controller on SH-Mobile SoCs requires even buffer addresses, when used
> with DMA.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

Cheers,
Samuel.

> ---
>  drivers/mfd/sh_mobile_sdhi.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
> index f1714f9..3ca20ec 100644
> --- a/drivers/mfd/sh_mobile_sdhi.c
> +++ b/drivers/mfd/sh_mobile_sdhi.c
> @@ -136,6 +136,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
>  		priv->param_rx.slave_id = p->dma_slave_rx;
>  		priv->dma_priv.chan_priv_tx = &priv->param_tx;
>  		priv->dma_priv.chan_priv_rx = &priv->param_rx;
> +		priv->dma_priv.alignment_shift = 1; /* 2-byte alignment */
>  		mmc_data->dma = &priv->dma_priv;
>  	}
>  
> -- 
> 1.7.2.3
> 

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with
  2010-11-23 16:24 ` Guennadi Liakhovetski
@ 2010-12-14 16:07   ` Guennadi Liakhovetski
  -1 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-12-14 16:07 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

Hi Ian

It's been 3 weeks... Have you had a chance to look at these and previous 
my tmio patches? Any comments or are they ok to go?

Thanks
Guennadi

On Tue, 23 Nov 2010, Guennadi Liakhovetski wrote:

> While testing SDIO on SuperH with TMIO and DMA, it turned out, that 
> buffers, submitted to the driver can be arbitrarily aligned, and this is 
> not handled by the tmio driver. This patch series fixes this issue.
> 
> Thanks
> Guennadi
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/
> 

---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with DMA
@ 2010-12-14 16:07   ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-12-14 16:07 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz

Hi Ian

It's been 3 weeks... Have you had a chance to look at these and previous 
my tmio patches? Any comments or are they ok to go?

Thanks
Guennadi

On Tue, 23 Nov 2010, Guennadi Liakhovetski wrote:

> While testing SDIO on SuperH with TMIO and DMA, it turned out, that 
> buffers, submitted to the driver can be arbitrarily aligned, and this is 
> not handled by the tmio driver. This patch series fixes this issue.
> 
> Thanks
> Guennadi
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/
> 

---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* [PATCH] mmc: tmio_mmc: silence compiler warnings
  2010-11-23 16:24   ` Guennadi Liakhovetski
  (?)
  (?)
@ 2010-12-19 21:16   ` Arnd Hannemann
  2011-01-05 20:48       ` Chris Ball
  -1 siblings, 1 reply; 31+ messages in thread
From: Arnd Hannemann @ 2010-12-19 21:16 UTC (permalink / raw)
  To: g.liakhovetski, linux-mmc
  Cc: linux-sh, Ian Molton, Samuel Ortiz, Arnd Hannemann

with "mmc: tmio: implement a bounce buffer for unaligned DMA"
gcc generates the following warnings:

drivers/mmc/host/tmio_mmc.c:654:6: warning: 'ret' may be used uninitialized in this function
drivers/mmc/host/tmio_mmc.c:730:6: warning: 'ret' may be used uninitialized in this function

This patch fixes these by setting ret to -EINVAL in the affected code paths.

This patch applies on top of -rc6 plus the following patches:
  mmc: tmio_mmc: allow multi-element scatter-gather lists
  mmc: tmio_mmc: fix PIO fallback on DMA descriptor allocation failure
  mmc: tmio: merge the private header into the driver
  mmc: tmio: implement a bounce buffer for unaligned DMA

Signed-off-by: Arnd Hannemann <arnd@arndnet.de>
---
 drivers/mmc/host/tmio_mmc.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 57ece9d..61e97d1 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -665,8 +665,10 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	}
 
 	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
-			  align >= MAX_ALIGN)) || !multiple)
+			  align >= MAX_ALIGN)) || !multiple) {
+		ret = -EINVAL;
 		goto pio;
+	}
 
 	/* The only sg element can be unaligned, use our bounce buffer then */
 	if (!aligned) {
@@ -741,8 +743,10 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	}
 
 	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
-			  align >= MAX_ALIGN)) || !multiple)
+			  align >= MAX_ALIGN)) || !multiple) {
+		ret = -EINVAL;
 		goto pio;
+	}
 
 	/* The only sg element can be unaligned, use our bounce buffer then */
 	if (!aligned) {
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned
  2010-11-23 16:24   ` Guennadi Liakhovetski
@ 2010-12-22 11:02     ` Guennadi Liakhovetski
  -1 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-12-22 11:02 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz, Magnus Damm

For example, with SDIO WLAN cards, some transfers happen with buffers at odd
addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
This patch extends the tmio driver with a bounce buffer, that is used for
single entry scatter-gather lists both for sending and receiving. If we ever
encounter unaligned transfers with multi-element sg lists, this patch will have
to be extended. For now it just falls back to PIO in this and other unsupported
cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---

v2:

1. fixed compilation without DMA support. Thanks to Magnus Damm 
<damm@opensource.se> for reporting

 drivers/mmc/host/tmio_mmc.c |   81 +++++++++++++++++++++++++++++++++++++++----
 include/linux/mfd/tmio.h    |    1 +
 2 files changed, 75 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 118ad86..eadf951 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -111,6 +111,8 @@
 		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
 	} while (0)
 
+/* This is arbitrary, just noone needed any higher alignment yet */
+#define MAX_ALIGN 4
 
 struct tmio_mmc_host {
 	void __iomem *ctl;
@@ -127,6 +129,7 @@ struct tmio_mmc_host {
 
 	/* pio related stuff */
 	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
 	unsigned int            sg_len;
 	unsigned int            sg_off;
 
@@ -139,9 +142,13 @@ struct tmio_mmc_host {
 	struct tasklet_struct	dma_issue;
 #ifdef CONFIG_TMIO_MMC_DMA
 	unsigned int            dma_sglen;
+	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
+	struct scatterlist	bounce_sg;
 #endif
 };
 
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host);
+
 static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
 {
 	return readw(host->ctl + (addr << host->bus_shift));
@@ -180,6 +187,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
 {
 	host->sg_len = data->sg_len;
 	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
 	host->sg_off = 0;
 }
 
@@ -438,6 +446,8 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 	if (data->flags & MMC_DATA_READ) {
 		if (!host->chan_rx)
 			disable_mmc_irqs(host, TMIO_MASK_READOP);
+		else
+			tmio_check_bounce_buffer(host);
 		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
 			host->mrq);
 	} else {
@@ -529,8 +539,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 			if (!host->chan_rx)
 				enable_mmc_irqs(host, TMIO_MASK_READOP);
 		} else {
-			struct dma_chan *chan = host->chan_tx;
-			if (!chan)
+			if (!host->chan_tx)
 				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 			else
 				tasklet_schedule(&host->dma_issue);
@@ -612,6 +621,16 @@ out:
 }
 
 #ifdef CONFIG_TMIO_MMC_DMA
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+	if (host->sg_ptr = &host->bounce_sg) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+	}
+}
+
 static void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
 {
 #if defined(CONFIG_SUPERH) || defined(CONFIG_ARCH_SHMOBILE)
@@ -634,11 +653,36 @@ static void tmio_dma_complete(void *arg)
 
 static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_rx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 	if (ret > 0) {
@@ -661,6 +705,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -684,11 +729,40 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 
 static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_tx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
 	if (ret > 0) {
@@ -709,6 +783,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -822,6 +897,10 @@ static void tmio_mmc_release_dma(struct tmio_mmc_host *host)
 	}
 }
 #else
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+}
+
 static void tmio_mmc_start_dma(struct tmio_mmc_host *host,
 			       struct mmc_data *data)
 {
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 085f041..dbfc053 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
 struct tmio_mmc_dma {
 	void *chan_priv_tx;
 	void *chan_priv_rx;
+	int alignment_shift;
 };
 
 /*
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2010-12-22 11:02     ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2010-12-22 11:02 UTC (permalink / raw)
  To: linux-mmc; +Cc: linux-sh, Ian Molton, Samuel Ortiz, Magnus Damm

For example, with SDIO WLAN cards, some transfers happen with buffers at odd
addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
This patch extends the tmio driver with a bounce buffer, that is used for
single entry scatter-gather lists both for sending and receiving. If we ever
encounter unaligned transfers with multi-element sg lists, this patch will have
to be extended. For now it just falls back to PIO in this and other unsupported
cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---

v2:

1. fixed compilation without DMA support. Thanks to Magnus Damm 
<damm@opensource.se> for reporting

 drivers/mmc/host/tmio_mmc.c |   81 +++++++++++++++++++++++++++++++++++++++----
 include/linux/mfd/tmio.h    |    1 +
 2 files changed, 75 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 118ad86..eadf951 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -111,6 +111,8 @@
 		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
 	} while (0)
 
+/* This is arbitrary, just noone needed any higher alignment yet */
+#define MAX_ALIGN 4
 
 struct tmio_mmc_host {
 	void __iomem *ctl;
@@ -127,6 +129,7 @@ struct tmio_mmc_host {
 
 	/* pio related stuff */
 	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
 	unsigned int            sg_len;
 	unsigned int            sg_off;
 
@@ -139,9 +142,13 @@ struct tmio_mmc_host {
 	struct tasklet_struct	dma_issue;
 #ifdef CONFIG_TMIO_MMC_DMA
 	unsigned int            dma_sglen;
+	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
+	struct scatterlist	bounce_sg;
 #endif
 };
 
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host);
+
 static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
 {
 	return readw(host->ctl + (addr << host->bus_shift));
@@ -180,6 +187,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
 {
 	host->sg_len = data->sg_len;
 	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
 	host->sg_off = 0;
 }
 
@@ -438,6 +446,8 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 	if (data->flags & MMC_DATA_READ) {
 		if (!host->chan_rx)
 			disable_mmc_irqs(host, TMIO_MASK_READOP);
+		else
+			tmio_check_bounce_buffer(host);
 		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
 			host->mrq);
 	} else {
@@ -529,8 +539,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 			if (!host->chan_rx)
 				enable_mmc_irqs(host, TMIO_MASK_READOP);
 		} else {
-			struct dma_chan *chan = host->chan_tx;
-			if (!chan)
+			if (!host->chan_tx)
 				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 			else
 				tasklet_schedule(&host->dma_issue);
@@ -612,6 +621,16 @@ out:
 }
 
 #ifdef CONFIG_TMIO_MMC_DMA
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+	if (host->sg_ptr == &host->bounce_sg) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+	}
+}
+
 static void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
 {
 #if defined(CONFIG_SUPERH) || defined(CONFIG_ARCH_SHMOBILE)
@@ -634,11 +653,36 @@ static void tmio_dma_complete(void *arg)
 
 static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_rx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 	if (ret > 0) {
@@ -661,6 +705,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -684,11 +729,40 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 
 static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_tx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		/* The first sg element unaligned, use our bounce-buffer */
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
 	if (ret > 0) {
@@ -709,6 +783,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -822,6 +897,10 @@ static void tmio_mmc_release_dma(struct tmio_mmc_host *host)
 	}
 }
 #else
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+}
+
 static void tmio_mmc_start_dma(struct tmio_mmc_host *host,
 			       struct mmc_data *data)
 {
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 085f041..dbfc053 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
 struct tmio_mmc_dma {
 	void *chan_priv_tx;
 	void *chan_priv_rx;
+	int alignment_shift;
 };
 
 /*
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for
  2010-12-22 11:02     ` [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned DMA Guennadi Liakhovetski
@ 2010-12-24 11:11       ` Samuel Ortiz
  -1 siblings, 0 replies; 31+ messages in thread
From: Samuel Ortiz @ 2010-12-24 11:11 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Magnus Damm

On Wed, Dec 22, 2010 at 12:02:15PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at odd
> addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
> This patch extends the tmio driver with a bounce buffer, that is used for
> single entry scatter-gather lists both for sending and receiving. If we ever
> encounter unaligned transfers with multi-element sg lists, this patch will have
> to be extended. For now it just falls back to PIO in this and other unsupported
> cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

for the MFD part.

Cheers,
Samuel.

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2010-12-24 11:11       ` Samuel Ortiz
  0 siblings, 0 replies; 31+ messages in thread
From: Samuel Ortiz @ 2010-12-24 11:11 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Magnus Damm

On Wed, Dec 22, 2010 at 12:02:15PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at odd
> addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
> This patch extends the tmio driver with a bounce buffer, that is used for
> single entry scatter-gather lists both for sending and receiving. If we ever
> encounter unaligned transfers with multi-element sg lists, this patch will have
> to be extended. For now it just falls back to PIO in this and other unsupported
> cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

for the MFD part.

Cheers,
Samuel.

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 1/3] mmc: tmio: merge the private header into the driver
  2010-11-23 16:24   ` Guennadi Liakhovetski
@ 2011-01-05 19:50     ` Chris Ball
  -1 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 19:50 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

On Tue, Nov 23, 2010 at 05:24:11PM +0100, Guennadi Liakhovetski wrote:
> drivers/mmc/host/tmio_mmc.h is only used by drivers/mmc/host/tmio_mmc.c, this
> needlessly complicates source-code handling.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

Ouch; but fixing it needlessly complicates patch handling, because now
all future patches apply or don't based on whether they saw this patch.
I think this decision should just be made once and lived with, without
a stronger reason than this one to change it.

I'll apply it since it's become a dependency now.  Pushed to mmc-next.

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 1/3] mmc: tmio: merge the private header into the driver
@ 2011-01-05 19:50     ` Chris Ball
  0 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 19:50 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

On Tue, Nov 23, 2010 at 05:24:11PM +0100, Guennadi Liakhovetski wrote:
> drivers/mmc/host/tmio_mmc.h is only used by drivers/mmc/host/tmio_mmc.c, this
> needlessly complicates source-code handling.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

Ouch; but fixing it needlessly complicates patch handling, because now
all future patches apply or don't based on whether they saw this patch.
I think this decision should just be made once and lived with, without
a stronger reason than this one to change it.

I'll apply it since it's become a dependency now.  Pushed to mmc-next.

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned
  2010-11-23 16:24   ` Guennadi Liakhovetski
@ 2011-01-05 19:56     ` Chris Ball
  -1 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 19:56 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

Hi Guennadi, could you resend this one with some style changes:

On Tue, Nov 23, 2010 at 05:24:15PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at odd
> addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
> This patch extends the tmio driver with a bounce buffer, that is used for
> single entry scatter-gather lists both for sending and receiving. If we ever
> encounter unaligned transfers with multi-element sg lists, this patch will have
> to be extended. For now it just falls back to PIO in this and other unsupported
> cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

Please wrap commit messages at 72 cols, not 80.

> ---
>  drivers/mmc/host/tmio_mmc.c |   81 +++++++++++++++++++++++++++++++++++++++----
>  include/linux/mfd/tmio.h    |    1 +
>  2 files changed, 75 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
> index 118ad86..57ece9d 100644
> --- a/drivers/mmc/host/tmio_mmc.c
> +++ b/drivers/mmc/host/tmio_mmc.c
> @@ -111,6 +111,8 @@
>  		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
>  	} while (0)
>  
> +/* This is arbitrary, just noone needed any higher alignment yet */
> +#define MAX_ALIGN 4
>  
>  struct tmio_mmc_host {
>  	void __iomem *ctl;
> @@ -127,6 +129,7 @@ struct tmio_mmc_host {
>  
>  	/* pio related stuff */
>  	struct scatterlist      *sg_ptr;
> +	struct scatterlist      *sg_orig;
>  	unsigned int            sg_len;
>  	unsigned int            sg_off;
>  
> @@ -139,6 +142,8 @@ struct tmio_mmc_host {
>  	struct tasklet_struct	dma_issue;
>  #ifdef CONFIG_TMIO_MMC_DMA
>  	unsigned int            dma_sglen;
> +	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
> +	struct scatterlist	bounce_sg;
>  #endif
>  };
>  
> @@ -180,6 +185,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
>  {
>  	host->sg_len = data->sg_len;
>  	host->sg_ptr = data->sg;
> +	host->sg_orig = data->sg;
>  	host->sg_off = 0;
>  }
>  
> @@ -436,8 +442,14 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
>  	 */
>  
>  	if (data->flags & MMC_DATA_READ) {
> -		if (!host->chan_rx)
> +		if (!host->chan_rx) {
>  			disable_mmc_irqs(host, TMIO_MASK_READOP);
> +		} else if (host->sg_ptr = &host->bounce_sg) {
> +			unsigned long flags;
> +			void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);

Would be nice to stay within 80-chars where possible.

> +			memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
> +			tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
> +		}
>  		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
>  			host->mrq);
>  	} else {
> @@ -529,8 +541,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
>  			if (!host->chan_rx)
>  				enable_mmc_irqs(host, TMIO_MASK_READOP);
>  		} else {
> -			struct dma_chan *chan = host->chan_tx;
> -			if (!chan)
> +			if (!host->chan_tx)
>  				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
>  			else
>  				tasklet_schedule(&host->dma_issue);
> @@ -634,11 +645,36 @@ static void tmio_dma_complete(void *arg)
>  
>  static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
>  {
> -	struct scatterlist *sg = host->sg_ptr;
> +	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
>  	struct dma_async_tx_descriptor *desc = NULL;
>  	struct dma_chan *chan = host->chan_rx;
> +	struct mfd_cell	*cell = host->pdev->dev.platform_data;
> +	struct tmio_mmc_data *pdata = cell->driver_data;
>  	dma_cookie_t cookie;
> -	int ret;
> +	int ret, i;
> +	bool aligned = true, multiple = true;
> +	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
> +
> +	for_each_sg(sg, sg_tmp, host->sg_len, i) {
> +		if (sg_tmp->offset & align)
> +			aligned = false;
> +		if (sg_tmp->length & align) {
> +			multiple = false;
> +			break;
> +		}
> +	}
> +
> +	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
> +			  align >= MAX_ALIGN)) || !multiple)
> +		goto pio;
> +
> +	/* The only sg element can be unaligned, use our bounce buffer then */
> +	if (!aligned) {
> +		/* The first sg element unaligned, use our bounce-buffer */
> +		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
> +		host->sg_ptr = &host->bounce_sg;
> +		sg = host->sg_ptr;
> +	}

The second comment is missing a verb, and looks redundant with the first.

>
>  	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
>  	if (ret > 0) {
> @@ -661,6 +697,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
>  	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
>  		__func__, host->sg_len, ret, cookie, host->mrq);
>  
> +pio:
>  	if (!desc) {
>  		/* DMA failed, fall back to PIO */
>  		if (ret >= 0)
> @@ -684,11 +721,40 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
>  
>  static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
>  {
> -	struct scatterlist *sg = host->sg_ptr;
> +	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
>  	struct dma_async_tx_descriptor *desc = NULL;
>  	struct dma_chan *chan = host->chan_tx;
> +	struct mfd_cell	*cell = host->pdev->dev.platform_data;
> +	struct tmio_mmc_data *pdata = cell->driver_data;
>  	dma_cookie_t cookie;
> -	int ret;
> +	int ret, i;
> +	bool aligned = true, multiple = true;
> +	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
> +
> +	for_each_sg(sg, sg_tmp, host->sg_len, i) {
> +		if (sg_tmp->offset & align)
> +			aligned = false;
> +		if (sg_tmp->length & align) {
> +			multiple = false;
> +			break;
> +		}
> +	}
> +
> +	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
> +			  align >= MAX_ALIGN)) || !multiple)
> +		goto pio;
> +
> +	/* The only sg element can be unaligned, use our bounce buffer then */
> +	if (!aligned) {
> +		unsigned long flags;
> +		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
> +		/* The first sg element unaligned, use our bounce-buffer */
> +		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
> +		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
> +		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
> +		host->sg_ptr = &host->bounce_sg;
> +		sg = host->sg_ptr;
> +	}

Same here.

>  
>  	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
>  	if (ret > 0) {
> @@ -709,6 +775,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
>  	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
>  		__func__, host->sg_len, ret, cookie, host->mrq);
>  
> +pio:
>  	if (!desc) {
>  		/* DMA failed, fall back to PIO */
>  		if (ret >= 0)
> diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
> index 085f041..dbfc053 100644
> --- a/include/linux/mfd/tmio.h
> +++ b/include/linux/mfd/tmio.h
> @@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
>  struct tmio_mmc_dma {
>  	void *chan_priv_tx;
>  	void *chan_priv_rx;
> +	int alignment_shift;
>  };
>  
>  /*

Thanks,

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2011-01-05 19:56     ` Chris Ball
  0 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 19:56 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

Hi Guennadi, could you resend this one with some style changes:

On Tue, Nov 23, 2010 at 05:24:15PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at odd
> addresses, whereas the SH-Mobile DMA engine requires even addresses for SDHI.
> This patch extends the tmio driver with a bounce buffer, that is used for
> single entry scatter-gather lists both for sending and receiving. If we ever
> encounter unaligned transfers with multi-element sg lists, this patch will have
> to be extended. For now it just falls back to PIO in this and other unsupported
> cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

Please wrap commit messages at 72 cols, not 80.

> ---
>  drivers/mmc/host/tmio_mmc.c |   81 +++++++++++++++++++++++++++++++++++++++----
>  include/linux/mfd/tmio.h    |    1 +
>  2 files changed, 75 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
> index 118ad86..57ece9d 100644
> --- a/drivers/mmc/host/tmio_mmc.c
> +++ b/drivers/mmc/host/tmio_mmc.c
> @@ -111,6 +111,8 @@
>  		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
>  	} while (0)
>  
> +/* This is arbitrary, just noone needed any higher alignment yet */
> +#define MAX_ALIGN 4
>  
>  struct tmio_mmc_host {
>  	void __iomem *ctl;
> @@ -127,6 +129,7 @@ struct tmio_mmc_host {
>  
>  	/* pio related stuff */
>  	struct scatterlist      *sg_ptr;
> +	struct scatterlist      *sg_orig;
>  	unsigned int            sg_len;
>  	unsigned int            sg_off;
>  
> @@ -139,6 +142,8 @@ struct tmio_mmc_host {
>  	struct tasklet_struct	dma_issue;
>  #ifdef CONFIG_TMIO_MMC_DMA
>  	unsigned int            dma_sglen;
> +	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
> +	struct scatterlist	bounce_sg;
>  #endif
>  };
>  
> @@ -180,6 +185,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
>  {
>  	host->sg_len = data->sg_len;
>  	host->sg_ptr = data->sg;
> +	host->sg_orig = data->sg;
>  	host->sg_off = 0;
>  }
>  
> @@ -436,8 +442,14 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
>  	 */
>  
>  	if (data->flags & MMC_DATA_READ) {
> -		if (!host->chan_rx)
> +		if (!host->chan_rx) {
>  			disable_mmc_irqs(host, TMIO_MASK_READOP);
> +		} else if (host->sg_ptr == &host->bounce_sg) {
> +			unsigned long flags;
> +			void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);

Would be nice to stay within 80-chars where possible.

> +			memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
> +			tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
> +		}
>  		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
>  			host->mrq);
>  	} else {
> @@ -529,8 +541,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
>  			if (!host->chan_rx)
>  				enable_mmc_irqs(host, TMIO_MASK_READOP);
>  		} else {
> -			struct dma_chan *chan = host->chan_tx;
> -			if (!chan)
> +			if (!host->chan_tx)
>  				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
>  			else
>  				tasklet_schedule(&host->dma_issue);
> @@ -634,11 +645,36 @@ static void tmio_dma_complete(void *arg)
>  
>  static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
>  {
> -	struct scatterlist *sg = host->sg_ptr;
> +	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
>  	struct dma_async_tx_descriptor *desc = NULL;
>  	struct dma_chan *chan = host->chan_rx;
> +	struct mfd_cell	*cell = host->pdev->dev.platform_data;
> +	struct tmio_mmc_data *pdata = cell->driver_data;
>  	dma_cookie_t cookie;
> -	int ret;
> +	int ret, i;
> +	bool aligned = true, multiple = true;
> +	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
> +
> +	for_each_sg(sg, sg_tmp, host->sg_len, i) {
> +		if (sg_tmp->offset & align)
> +			aligned = false;
> +		if (sg_tmp->length & align) {
> +			multiple = false;
> +			break;
> +		}
> +	}
> +
> +	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
> +			  align >= MAX_ALIGN)) || !multiple)
> +		goto pio;
> +
> +	/* The only sg element can be unaligned, use our bounce buffer then */
> +	if (!aligned) {
> +		/* The first sg element unaligned, use our bounce-buffer */
> +		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
> +		host->sg_ptr = &host->bounce_sg;
> +		sg = host->sg_ptr;
> +	}

The second comment is missing a verb, and looks redundant with the first.

>
>  	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
>  	if (ret > 0) {
> @@ -661,6 +697,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
>  	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
>  		__func__, host->sg_len, ret, cookie, host->mrq);
>  
> +pio:
>  	if (!desc) {
>  		/* DMA failed, fall back to PIO */
>  		if (ret >= 0)
> @@ -684,11 +721,40 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
>  
>  static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
>  {
> -	struct scatterlist *sg = host->sg_ptr;
> +	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
>  	struct dma_async_tx_descriptor *desc = NULL;
>  	struct dma_chan *chan = host->chan_tx;
> +	struct mfd_cell	*cell = host->pdev->dev.platform_data;
> +	struct tmio_mmc_data *pdata = cell->driver_data;
>  	dma_cookie_t cookie;
> -	int ret;
> +	int ret, i;
> +	bool aligned = true, multiple = true;
> +	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
> +
> +	for_each_sg(sg, sg_tmp, host->sg_len, i) {
> +		if (sg_tmp->offset & align)
> +			aligned = false;
> +		if (sg_tmp->length & align) {
> +			multiple = false;
> +			break;
> +		}
> +	}
> +
> +	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
> +			  align >= MAX_ALIGN)) || !multiple)
> +		goto pio;
> +
> +	/* The only sg element can be unaligned, use our bounce buffer then */
> +	if (!aligned) {
> +		unsigned long flags;
> +		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
> +		/* The first sg element unaligned, use our bounce-buffer */
> +		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
> +		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
> +		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
> +		host->sg_ptr = &host->bounce_sg;
> +		sg = host->sg_ptr;
> +	}

Same here.

>  
>  	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
>  	if (ret > 0) {
> @@ -709,6 +775,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
>  	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
>  		__func__, host->sg_len, ret, cookie, host->mrq);
>  
> +pio:
>  	if (!desc) {
>  		/* DMA failed, fall back to PIO */
>  		if (ret >= 0)
> diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
> index 085f041..dbfc053 100644
> --- a/include/linux/mfd/tmio.h
> +++ b/include/linux/mfd/tmio.h
> @@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
>  struct tmio_mmc_dma {
>  	void *chan_priv_tx;
>  	void *chan_priv_rx;
> +	int alignment_shift;
>  };
>  
>  /*

Thanks,

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH] mmc: tmio_mmc: silence compiler warnings
  2010-12-19 21:16   ` [PATCH] mmc: tmio_mmc: silence compiler warnings Arnd Hannemann
@ 2011-01-05 20:48       ` Chris Ball
  0 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 20:48 UTC (permalink / raw)
  To: Arnd Hannemann
  Cc: g.liakhovetski, linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

On Sun, Dec 19, 2010 at 09:16:07PM +0000, Arnd Hannemann wrote:
> with "mmc: tmio: implement a bounce buffer for unaligned DMA"
> gcc generates the following warnings:
> 
> drivers/mmc/host/tmio_mmc.c:654:6: warning: 'ret' may be used uninitialized in this function
> drivers/mmc/host/tmio_mmc.c:730:6: warning: 'ret' may be used uninitialized in this function
> 
> This patch fixes these by setting ret to -EINVAL in the affected code paths.
> 
> This patch applies on top of -rc6 plus the following patches:
>   mmc: tmio_mmc: allow multi-element scatter-gather lists
>   mmc: tmio_mmc: fix PIO fallback on DMA descriptor allocation failure
>   mmc: tmio: merge the private header into the driver
>   mmc: tmio: implement a bounce buffer for unaligned DMA
> 
> Signed-off-by: Arnd Hannemann <arnd@arndnet.de>

Thanks, pushed to mmc-next for .38.

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH] mmc: tmio_mmc: silence compiler warnings
@ 2011-01-05 20:48       ` Chris Ball
  0 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 20:48 UTC (permalink / raw)
  To: Arnd Hannemann
  Cc: g.liakhovetski, linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

On Sun, Dec 19, 2010 at 09:16:07PM +0000, Arnd Hannemann wrote:
> with "mmc: tmio: implement a bounce buffer for unaligned DMA"
> gcc generates the following warnings:
> 
> drivers/mmc/host/tmio_mmc.c:654:6: warning: 'ret' may be used uninitialized in this function
> drivers/mmc/host/tmio_mmc.c:730:6: warning: 'ret' may be used uninitialized in this function
> 
> This patch fixes these by setting ret to -EINVAL in the affected code paths.
> 
> This patch applies on top of -rc6 plus the following patches:
>   mmc: tmio_mmc: allow multi-element scatter-gather lists
>   mmc: tmio_mmc: fix PIO fallback on DMA descriptor allocation failure
>   mmc: tmio: merge the private header into the driver
>   mmc: tmio: implement a bounce buffer for unaligned DMA
> 
> Signed-off-by: Arnd Hannemann <arnd@arndnet.de>

Thanks, pushed to mmc-next for .38.

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce
  2010-11-23 16:24   ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers Guennadi Liakhovetski
@ 2011-01-05 20:49     ` Chris Ball
  -1 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 20:49 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

On Tue, Nov 23, 2010 at 05:24:19PM +0100, Guennadi Liakhovetski wrote:
> The SDHI controller on SH-Mobile SoCs requires even buffer addresses, when used
> with DMA.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
>  drivers/mfd/sh_mobile_sdhi.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
> index f1714f9..3ca20ec 100644
> --- a/drivers/mfd/sh_mobile_sdhi.c
> +++ b/drivers/mfd/sh_mobile_sdhi.c
> @@ -136,6 +136,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
>  		priv->param_rx.slave_id = p->dma_slave_rx;
>  		priv->dma_priv.chan_priv_tx = &priv->param_tx;
>  		priv->dma_priv.chan_priv_rx = &priv->param_rx;
> +		priv->dma_priv.alignment_shift = 1; /* 2-byte alignment */
>  		mmc_data->dma = &priv->dma_priv;
>  	}
>  

Pushed to mmc-next for .38, thanks.

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers
@ 2011-01-05 20:49     ` Chris Ball
  0 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 20:49 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

On Tue, Nov 23, 2010 at 05:24:19PM +0100, Guennadi Liakhovetski wrote:
> The SDHI controller on SH-Mobile SoCs requires even buffer addresses, when used
> with DMA.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
>  drivers/mfd/sh_mobile_sdhi.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/mfd/sh_mobile_sdhi.c b/drivers/mfd/sh_mobile_sdhi.c
> index f1714f9..3ca20ec 100644
> --- a/drivers/mfd/sh_mobile_sdhi.c
> +++ b/drivers/mfd/sh_mobile_sdhi.c
> @@ -136,6 +136,7 @@ static int __devinit sh_mobile_sdhi_probe(struct platform_device *pdev)
>  		priv->param_rx.slave_id = p->dma_slave_rx;
>  		priv->dma_priv.chan_priv_tx = &priv->param_tx;
>  		priv->dma_priv.chan_priv_rx = &priv->param_rx;
> +		priv->dma_priv.alignment_shift = 1; /* 2-byte alignment */
>  		mmc_data->dma = &priv->dma_priv;
>  	}
>  

Pushed to mmc-next for .38, thanks.

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned
  2011-01-05 19:56     ` [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA Chris Ball
@ 2011-01-05 20:56       ` Guennadi Liakhovetski
  -1 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2011-01-05 20:56 UTC (permalink / raw)
  To: Chris Ball; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

For example, with SDIO WLAN cards, some transfers happen with buffers at
odd addresses, whereas the SH-Mobile DMA engine requires even addresses
for SDHI. This patch extends the tmio driver with a bounce buffer, that
is used for single entry scatter-gather lists both for sending and
receiving. If we ever encounter unaligned transfers with multi-element
sg lists, this patch will have to be extended. For now it just falls
back to PIO in this and other unsupported cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---

Chris, thanks for your comments, but you picked up a wrong version of this 
patch. Please, use links from my "outstanding patches" email.

v3:

1. wrapped patch description at 72 chars instead of 80
2. removed two redundant comment lines

v2:

1. fixed compilation without DMA support. Thanks to Magnus Damm 
<damm@opensource.se> for reporting

 drivers/mmc/host/tmio_mmc.c |   89 ++++++++++++++++++++++++++++++++++++++++---
 include/linux/mfd/tmio.h    |    1 +
 2 files changed, 84 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 118ad86..d8163c1 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -111,6 +111,8 @@
 		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
 	} while (0)
 
+/* This is arbitrary, just noone needed any higher alignment yet */
+#define MAX_ALIGN 4
 
 struct tmio_mmc_host {
 	void __iomem *ctl;
@@ -127,6 +129,7 @@ struct tmio_mmc_host {
 
 	/* pio related stuff */
 	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
 	unsigned int            sg_len;
 	unsigned int            sg_off;
 
@@ -139,9 +142,13 @@ struct tmio_mmc_host {
 	struct tasklet_struct	dma_issue;
 #ifdef CONFIG_TMIO_MMC_DMA
 	unsigned int            dma_sglen;
+	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
+	struct scatterlist	bounce_sg;
 #endif
 };
 
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host);
+
 static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
 {
 	return readw(host->ctl + (addr << host->bus_shift));
@@ -180,6 +187,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
 {
 	host->sg_len = data->sg_len;
 	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
 	host->sg_off = 0;
 }
 
@@ -438,6 +446,8 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 	if (data->flags & MMC_DATA_READ) {
 		if (!host->chan_rx)
 			disable_mmc_irqs(host, TMIO_MASK_READOP);
+		else
+			tmio_check_bounce_buffer(host);
 		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
 			host->mrq);
 	} else {
@@ -529,8 +539,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 			if (!host->chan_rx)
 				enable_mmc_irqs(host, TMIO_MASK_READOP);
 		} else {
-			struct dma_chan *chan = host->chan_tx;
-			if (!chan)
+			if (!host->chan_tx)
 				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 			else
 				tasklet_schedule(&host->dma_issue);
@@ -612,6 +621,16 @@ out:
 }
 
 #ifdef CONFIG_TMIO_MMC_DMA
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+	if (host->sg_ptr = &host->bounce_sg) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+	}
+}
+
 static void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
 {
 #if defined(CONFIG_SUPERH) || defined(CONFIG_ARCH_SHMOBILE)
@@ -634,11 +653,35 @@ static void tmio_dma_complete(void *arg)
 
 static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_rx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 	if (ret > 0) {
@@ -661,6 +704,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -684,11 +728,39 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 
 static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_tx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
 	if (ret > 0) {
@@ -709,6 +781,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -822,6 +895,10 @@ static void tmio_mmc_release_dma(struct tmio_mmc_host *host)
 	}
 }
 #else
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+}
+
 static void tmio_mmc_start_dma(struct tmio_mmc_host *host,
 			       struct mmc_data *data)
 {
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 085f041..dbfc053 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
 struct tmio_mmc_dma {
 	void *chan_priv_tx;
 	void *chan_priv_rx;
+	int alignment_shift;
 };
 
 /*
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2011-01-05 20:56       ` Guennadi Liakhovetski
  0 siblings, 0 replies; 31+ messages in thread
From: Guennadi Liakhovetski @ 2011-01-05 20:56 UTC (permalink / raw)
  To: Chris Ball; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

For example, with SDIO WLAN cards, some transfers happen with buffers at
odd addresses, whereas the SH-Mobile DMA engine requires even addresses
for SDHI. This patch extends the tmio driver with a bounce buffer, that
is used for single entry scatter-gather lists both for sending and
receiving. If we ever encounter unaligned transfers with multi-element
sg lists, this patch will have to be extended. For now it just falls
back to PIO in this and other unsupported cases.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---

Chris, thanks for your comments, but you picked up a wrong version of this 
patch. Please, use links from my "outstanding patches" email.

v3:

1. wrapped patch description at 72 chars instead of 80
2. removed two redundant comment lines

v2:

1. fixed compilation without DMA support. Thanks to Magnus Damm 
<damm@opensource.se> for reporting

 drivers/mmc/host/tmio_mmc.c |   89 ++++++++++++++++++++++++++++++++++++++++---
 include/linux/mfd/tmio.h    |    1 +
 2 files changed, 84 insertions(+), 6 deletions(-)

diff --git a/drivers/mmc/host/tmio_mmc.c b/drivers/mmc/host/tmio_mmc.c
index 118ad86..d8163c1 100644
--- a/drivers/mmc/host/tmio_mmc.c
+++ b/drivers/mmc/host/tmio_mmc.c
@@ -111,6 +111,8 @@
 		sd_ctrl_write32((host), CTL_STATUS, ~(i)); \
 	} while (0)
 
+/* This is arbitrary, just noone needed any higher alignment yet */
+#define MAX_ALIGN 4
 
 struct tmio_mmc_host {
 	void __iomem *ctl;
@@ -127,6 +129,7 @@ struct tmio_mmc_host {
 
 	/* pio related stuff */
 	struct scatterlist      *sg_ptr;
+	struct scatterlist      *sg_orig;
 	unsigned int            sg_len;
 	unsigned int            sg_off;
 
@@ -139,9 +142,13 @@ struct tmio_mmc_host {
 	struct tasklet_struct	dma_issue;
 #ifdef CONFIG_TMIO_MMC_DMA
 	unsigned int            dma_sglen;
+	u8			bounce_buf[PAGE_CACHE_SIZE] __attribute__((aligned(MAX_ALIGN)));
+	struct scatterlist	bounce_sg;
 #endif
 };
 
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host);
+
 static u16 sd_ctrl_read16(struct tmio_mmc_host *host, int addr)
 {
 	return readw(host->ctl + (addr << host->bus_shift));
@@ -180,6 +187,7 @@ static void tmio_mmc_init_sg(struct tmio_mmc_host *host, struct mmc_data *data)
 {
 	host->sg_len = data->sg_len;
 	host->sg_ptr = data->sg;
+	host->sg_orig = data->sg;
 	host->sg_off = 0;
 }
 
@@ -438,6 +446,8 @@ static void tmio_mmc_do_data_irq(struct tmio_mmc_host *host)
 	if (data->flags & MMC_DATA_READ) {
 		if (!host->chan_rx)
 			disable_mmc_irqs(host, TMIO_MASK_READOP);
+		else
+			tmio_check_bounce_buffer(host);
 		dev_dbg(&host->pdev->dev, "Complete Rx request %p\n",
 			host->mrq);
 	} else {
@@ -529,8 +539,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host,
 			if (!host->chan_rx)
 				enable_mmc_irqs(host, TMIO_MASK_READOP);
 		} else {
-			struct dma_chan *chan = host->chan_tx;
-			if (!chan)
+			if (!host->chan_tx)
 				enable_mmc_irqs(host, TMIO_MASK_WRITEOP);
 			else
 				tasklet_schedule(&host->dma_issue);
@@ -612,6 +621,16 @@ out:
 }
 
 #ifdef CONFIG_TMIO_MMC_DMA
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+	if (host->sg_ptr == &host->bounce_sg) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(host->sg_orig, &flags);
+		memcpy(sg_vaddr, host->bounce_buf, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+	}
+}
+
 static void tmio_mmc_enable_dma(struct tmio_mmc_host *host, bool enable)
 {
 #if defined(CONFIG_SUPERH) || defined(CONFIG_ARCH_SHMOBILE)
@@ -634,11 +653,35 @@ static void tmio_dma_complete(void *arg)
 
 static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_rx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_FROM_DEVICE);
 	if (ret > 0) {
@@ -661,6 +704,7 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -684,11 +728,39 @@ static void tmio_mmc_start_dma_rx(struct tmio_mmc_host *host)
 
 static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 {
-	struct scatterlist *sg = host->sg_ptr;
+	struct scatterlist *sg = host->sg_ptr, *sg_tmp;
 	struct dma_async_tx_descriptor *desc = NULL;
 	struct dma_chan *chan = host->chan_tx;
+	struct mfd_cell	*cell = host->pdev->dev.platform_data;
+	struct tmio_mmc_data *pdata = cell->driver_data;
 	dma_cookie_t cookie;
-	int ret;
+	int ret, i;
+	bool aligned = true, multiple = true;
+	unsigned int align = (1 << pdata->dma->alignment_shift) - 1;
+
+	for_each_sg(sg, sg_tmp, host->sg_len, i) {
+		if (sg_tmp->offset & align)
+			aligned = false;
+		if (sg_tmp->length & align) {
+			multiple = false;
+			break;
+		}
+	}
+
+	if ((!aligned && (host->sg_len > 1 || sg->length > PAGE_CACHE_SIZE ||
+			  align >= MAX_ALIGN)) || !multiple)
+		goto pio;
+
+	/* The only sg element can be unaligned, use our bounce buffer then */
+	if (!aligned) {
+		unsigned long flags;
+		void *sg_vaddr = tmio_mmc_kmap_atomic(sg, &flags);
+		sg_init_one(&host->bounce_sg, host->bounce_buf, sg->length);
+		memcpy(host->bounce_buf, sg_vaddr, host->bounce_sg.length);
+		tmio_mmc_kunmap_atomic(sg_vaddr, &flags);
+		host->sg_ptr = &host->bounce_sg;
+		sg = host->sg_ptr;
+	}
 
 	ret = dma_map_sg(&host->pdev->dev, sg, host->sg_len, DMA_TO_DEVICE);
 	if (ret > 0) {
@@ -709,6 +781,7 @@ static void tmio_mmc_start_dma_tx(struct tmio_mmc_host *host)
 	dev_dbg(&host->pdev->dev, "%s(): mapped %d -> %d, cookie %d, rq %p\n",
 		__func__, host->sg_len, ret, cookie, host->mrq);
 
+pio:
 	if (!desc) {
 		/* DMA failed, fall back to PIO */
 		if (ret >= 0)
@@ -822,6 +895,10 @@ static void tmio_mmc_release_dma(struct tmio_mmc_host *host)
 	}
 }
 #else
+static void tmio_check_bounce_buffer(struct tmio_mmc_host *host)
+{
+}
+
 static void tmio_mmc_start_dma(struct tmio_mmc_host *host,
 			       struct mmc_data *data)
 {
diff --git a/include/linux/mfd/tmio.h b/include/linux/mfd/tmio.h
index 085f041..dbfc053 100644
--- a/include/linux/mfd/tmio.h
+++ b/include/linux/mfd/tmio.h
@@ -66,6 +66,7 @@ void tmio_core_mmc_clk_div(void __iomem *cnf, int shift, int state);
 struct tmio_mmc_dma {
 	void *chan_priv_tx;
 	void *chan_priv_rx;
+	int alignment_shift;
 };
 
 /*
-- 
1.7.2.3


^ permalink raw reply related	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for
  2011-01-05 20:56       ` [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned DMA Guennadi Liakhovetski
@ 2011-01-05 21:06         ` Chris Ball
  -1 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 21:06 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

Hi Guennadi,

On Wed, Jan 05, 2011 at 09:56:01PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at
> odd addresses, whereas the SH-Mobile DMA engine requires even addresses
> for SDHI. This patch extends the tmio driver with a bounce buffer, that
> is used for single entry scatter-gather lists both for sending and
> receiving. If we ever encounter unaligned transfers with multi-element
> sg lists, this patch will have to be extended. For now it just falls
> back to PIO in this and other unsupported cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
> 
> Chris, thanks for your comments, but you picked up a wrong version of this 
> patch. Please, use links from my "outstanding patches" email.

Thanks.  Actually, I got the right patch but then replied to the wrong
e-mail.  :)  Pushed v3 to mmc-next now. 

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

* Re: [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned DMA
@ 2011-01-05 21:06         ` Chris Ball
  0 siblings, 0 replies; 31+ messages in thread
From: Chris Ball @ 2011-01-05 21:06 UTC (permalink / raw)
  To: Guennadi Liakhovetski; +Cc: linux-mmc, linux-sh, Ian Molton, Samuel Ortiz

Hi Guennadi,

On Wed, Jan 05, 2011 at 09:56:01PM +0100, Guennadi Liakhovetski wrote:
> For example, with SDIO WLAN cards, some transfers happen with buffers at
> odd addresses, whereas the SH-Mobile DMA engine requires even addresses
> for SDHI. This patch extends the tmio driver with a bounce buffer, that
> is used for single entry scatter-gather lists both for sending and
> receiving. If we ever encounter unaligned transfers with multi-element
> sg lists, this patch will have to be extended. For now it just falls
> back to PIO in this and other unsupported cases.
> 
> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
> ---
> 
> Chris, thanks for your comments, but you picked up a wrong version of this 
> patch. Please, use links from my "outstanding patches" email.

Thanks.  Actually, I got the right patch but then replied to the wrong
e-mail.  :)  Pushed v3 to mmc-next now. 

-- 
Chris Ball   <cjb@laptop.org>   <http://printf.net/>
One Laptop Per Child

^ permalink raw reply	[flat|nested] 31+ messages in thread

end of thread, other threads:[~2011-01-05 21:06 UTC | newest]

Thread overview: 31+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2010-11-23 16:24 [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with DMA Guennadi Liakhovetski
2010-11-23 16:24 ` Guennadi Liakhovetski
2010-11-23 16:24 ` [PATCH 1/3] mmc: tmio: merge the private header into the driver Guennadi Liakhovetski
2010-11-23 16:24   ` Guennadi Liakhovetski
2011-01-05 19:50   ` Chris Ball
2011-01-05 19:50     ` Chris Ball
2010-11-23 16:24 ` [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA Guennadi Liakhovetski
2010-11-23 16:24   ` Guennadi Liakhovetski
2010-11-26 12:04   ` [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned Samuel Ortiz
2010-11-26 12:04     ` [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA Samuel Ortiz
2010-12-19 21:16   ` [PATCH] mmc: tmio_mmc: silence compiler warnings Arnd Hannemann
2011-01-05 20:48     ` Chris Ball
2011-01-05 20:48       ` Chris Ball
2010-12-22 11:02   ` [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned Guennadi Liakhovetski
2010-12-22 11:02     ` [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned DMA Guennadi Liakhovetski
2010-12-24 11:11     ` [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for Samuel Ortiz
2010-12-24 11:11       ` [PATCH 2/3 v2] mmc: tmio: implement a bounce buffer for unaligned DMA Samuel Ortiz
2011-01-05 19:56   ` [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned Chris Ball
2011-01-05 19:56     ` [PATCH 2/3] mmc: tmio: implement a bounce buffer for unaligned DMA Chris Ball
2011-01-05 20:56     ` [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned Guennadi Liakhovetski
2011-01-05 20:56       ` [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned DMA Guennadi Liakhovetski
2011-01-05 21:06       ` [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for Chris Ball
2011-01-05 21:06         ` [PATCH 2/3 v3] mmc: tmio: implement a bounce buffer for unaligned DMA Chris Ball
2010-11-23 16:24 ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned Guennadi Liakhovetski
2010-11-23 16:24   ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers Guennadi Liakhovetski
2010-11-26 12:05   ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce Samuel Ortiz
2010-11-26 12:05     ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers Samuel Ortiz
2011-01-05 20:49   ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce Chris Ball
2011-01-05 20:49     ` [PATCH 3/3] mfd: sdhi: require the tmio-mmc driver to bounce unaligned buffers Chris Ball
2010-12-14 16:07 ` [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with Guennadi Liakhovetski
2010-12-14 16:07   ` [PATCH 0/3] handle unaligned buffers, when using TMIO-MMC with DMA Guennadi Liakhovetski

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