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* [PATCH] mmc: at91_mci: fix hanging and rework to match flowcharts
@ 2007-07-02 12:16 Nicolas Ferre
  2007-07-02 12:45 ` Marc Pignat
                   ` (3 more replies)
  0 siblings, 4 replies; 8+ messages in thread
From: Nicolas Ferre @ 2007-07-02 12:16 UTC (permalink / raw)
  To: Pierre Ossman, ARM Linux Mailing List
  Cc: Linux Kernel list, Andrew Victor, Andreas Beier, Hamish Guthrie,
	Marc Pignat, wux, Patrice Vilchez

Fixes hanging using multi block operations (seen during CMD25).
Follows closely the datasheet flowcharts.

This piece of code handles better big file writing. I had to take 
care of the notbusy signal during write (at91_mci_handle_cmdrdy 
function) and to rearrange the AT91_MCI_ENDRX and AT91_MCI_RXBUFF 
flag usage.

Signed-off-by: Nicolas Ferre <nicolas.ferre@rfo.atmel.com>
---
This patch is applied on top of the "typo" one :
http://kernel.org/pub/linux/kernel/people/akpm/patches/2.6/2.6.22-rc6/2.6.22-rc6-mm1/broken-out/mmc-at91_mci-typo.patch

It is cooked with the help of Wu Xuan and Marc Pignat. Big thanks to 
them.

It has been tested on several systems and reported to work ok :
at91rm9200 ok w/ 1 wire
at91sam9261 ok w/ 1 wire
at91sam926[03] ok w/ 4 wires
The code takes care of those specificities.

 drivers/mmc/host/at91_mci.c |  213 ++++++++++++++++++----------------
 1 file changed, 118 insertions(+), 95 deletions(-)

Index: b/drivers/mmc/host/at91_mci.c
===================================================================
--- a/drivers/mmc/host/at91_mci.c
+++ b/drivers/mmc/host/at91_mci.c
@@ -80,8 +78,6 @@
 
 #define DRIVER_NAME "at91_mci"
 
-#undef	SUPPORT_4WIRE
-
 #define FL_SENT_COMMAND	(1 << 0)
 #define FL_SENT_STOP	(1 << 1)
 
@@ -250,28 +246,27 @@ static void at91_mci_pre_dma_read(struct
 /*
  * Handle after a dma read
  */
-static void at91_mci_post_dma_read(struct at91mci_host *host)
+static int at91_mci_post_dma_read(struct at91mci_host *host)
 {
 	struct mmc_command *cmd;
 	struct mmc_data *data;
+	int completed = 0;
 
 	pr_debug("post dma read\n");
 
 	cmd = host->cmd;
 	if (!cmd) {
 		pr_debug("no command\n");
-		return;
+		return 1;
 	}
 
 	data = cmd->data;
 	if (!data) {
 		pr_debug("no data\n");
-		return;
+		return 1;
 	}
 
 	while (host->in_use_index < host->transfer_index) {
-		unsigned int *buffer;
-
 		struct scatterlist *sg;
 
 		pr_debug("finishing index %d\n", host->in_use_index);
@@ -282,20 +277,22 @@ static void at91_mci_post_dma_read(struc
 
 		dma_unmap_page(NULL, sg->dma_address, sg->length, DMA_FROM_DEVICE);
 
-		/* Swap the contents of the buffer */
-		buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset;
-		pr_debug("buffer = %p, length = %d\n", buffer, sg->length);
-
 		data->bytes_xfered += sg->length;
 
 		if (cpu_is_at91rm9200()) {	/* AT91RM9200 errata */
+			unsigned int *buffer;
 			int index;
 
+			/* Swap the contents of the buffer */
+			buffer = kmap_atomic(sg->page, KM_BIO_SRC_IRQ) + sg->offset;
+			pr_debug("buffer = %p, length = %d\n", buffer, sg->length);
+
 			for (index = 0; index < (sg->length / 4); index++)
 				buffer[index] = swab32(buffer[index]);
+
+			kunmap_atomic(buffer, KM_BIO_SRC_IRQ);
 		}
 
-		kunmap_atomic(buffer, KM_BIO_SRC_IRQ);
 		flush_dcache_page(sg->page);
 	}
 
@@ -303,11 +300,12 @@ static void at91_mci_post_dma_read(struc
 	if (host->transfer_index < data->sg_len)
 		at91_mci_pre_dma_read(host);
 	else {
+		at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_ENDRX);
 		at91_mci_write(host, AT91_MCI_IER, AT91_MCI_RXBUFF);
-		at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
 	}
 
 	pr_debug("post dma read done\n");
+	return completed;
 }
 
 /*
@@ -325,7 +323,6 @@ static void at91_mci_handle_transmitted(
 
 	/* Now wait for cmd ready */
 	at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_TXBUFE);
-	at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY);
 
 	cmd = host->cmd;
 	if (!cmd) return;
@@ -333,18 +330,53 @@ static void at91_mci_handle_transmitted(
 	data = cmd->data;
 	if (!data) return;
 
+	if (cmd->data->flags & MMC_DATA_MULTI) {
+		pr_debug("multiple write : wait for BLKE...\n");
+		at91_mci_write(host, AT91_MCI_IER, AT91_MCI_BLKE);
+	} else
+		at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY);
+
 	data->bytes_xfered = host->total_length;
 }
 
+/*Handle after command sent ready*/
+static int at91_mci_handle_cmdrdy(struct at91mci_host *host)
+{
+	if (!host->cmd)
+		return 1;
+	else if (!host->cmd->data) {
+		if (host->flags & FL_SENT_STOP) {
+			/*After multi block write, we must wait for NOTBUSY*/
+			at91_mci_write(host, AT91_MCI_IER, AT91_MCI_NOTBUSY);
+		} else return 1;
+	} else if (host->cmd->data->flags & MMC_DATA_WRITE) {
+		/*After sendding multi-block-write command, start DMA transfer*/
+		at91_mci_write(host, AT91_MCI_IER, AT91_MCI_TXBUFE);
+		at91_mci_write(host, AT91_MCI_IER, AT91_MCI_BLKE);
+		at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
+	}
+
+	/* command not completed, have to wait */
+	return 0;
+}
+
+
 /*
  * Enable the controller
  */
 static void at91_mci_enable(struct at91mci_host *host)
 {
+	unsigned int mr;
+
 	at91_mci_write(host, AT91_MCI_CR, AT91_MCI_MCIEN);
 	at91_mci_write(host, AT91_MCI_IDR, 0xffffffff);
 	at91_mci_write(host, AT91_MCI_DTOR, AT91_MCI_DTOMUL_1M | AT91_MCI_DTOCYC);
-	at91_mci_write(host, AT91_MCI_MR, AT91_MCI_PDCMODE | 0x34a);
+	mr = AT91_MCI_PDCMODE | 0x34a;
+
+	if (cpu_is_at91sam9260() || cpu_is_at91sam9263())
+		mr |= AT91_MCI_RDPROOF | AT91_MCI_WRPROOF;
+
+	at91_mci_write(host, AT91_MCI_MR, mr);
 
 	/* use Slot A or B (only one at same time) */
 	at91_mci_write(host, AT91_MCI_SDCR, host->board->slot_b);
@@ -360,9 +392,8 @@ static void at91_mci_disable(struct at91
 
 /*
  * Send a command
- * return the interrupts to enable
  */
-static unsigned int at91_mci_send_command(struct at91mci_host *host, struct mmc_command *cmd)
+static void at91_mci_send_command(struct at91mci_host *host, struct mmc_command *cmd)
 {
 	unsigned int cmdr, mr;
 	unsigned int block_length;
@@ -373,8 +404,7 @@ static unsigned int at91_mci_send_comman
 
 	host->cmd = cmd;
 
-	/* Not sure if this is needed */
-#if 0
+	/* Needed for leaving busy state before CMD1 */
 	if ((at91_mci_read(host, AT91_MCI_SR) & AT91_MCI_RTOE) && (cmd->opcode == 1)) {
 		pr_debug("Clearing timeout\n");
 		at91_mci_write(host, AT91_MCI_ARGR, 0);
@@ -384,7 +414,7 @@ static unsigned int at91_mci_send_comman
 			pr_debug("Clearing: SR = %08X\n", at91_mci_read(host, AT91_MCI_SR));
 		}
 	}
-#endif
+
 	cmdr = cmd->opcode;
 
 	if (mmc_resp_type(cmd) == MMC_RSP_NONE)
@@ -441,50 +471,48 @@ static unsigned int at91_mci_send_comman
 		at91_mci_write(host, ATMEL_PDC_TCR, 0);
 		at91_mci_write(host, ATMEL_PDC_TNPR, 0);
 		at91_mci_write(host, ATMEL_PDC_TNCR, 0);
+		ier = AT91_MCI_CMDRDY;
+	} else {
+		/* zero block length and PDC mode */
+		mr = at91_mci_read(host, AT91_MCI_MR) & 0x7fff;
+		at91_mci_write(host, AT91_MCI_MR, mr | (block_length << 16) | AT91_MCI_PDCMODE);
+
+		/*
+		 * Disable the PDC controller
+		 */
+		at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
 
-		at91_mci_write(host, AT91_MCI_ARGR, cmd->arg);
-		at91_mci_write(host, AT91_MCI_CMDR, cmdr);
-		return AT91_MCI_CMDRDY;
-	}
-
-	mr = at91_mci_read(host, AT91_MCI_MR) & 0x7fff;	/* zero block length and PDC mode */
-	at91_mci_write(host, AT91_MCI_MR, mr | (block_length << 16) | AT91_MCI_PDCMODE);
-
-	/*
-	 * Disable the PDC controller
-	 */
-	at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
-
-	if (cmdr & AT91_MCI_TRCMD_START) {
-		data->bytes_xfered = 0;
-		host->transfer_index = 0;
-		host->in_use_index = 0;
-		if (cmdr & AT91_MCI_TRDIR) {
-			/*
-			 * Handle a read
-			 */
-			host->buffer = NULL;
-			host->total_length = 0;
+		if (cmdr & AT91_MCI_TRCMD_START) {
+			data->bytes_xfered = 0;
+			host->transfer_index = 0;
+			host->in_use_index = 0;
+			if (cmdr & AT91_MCI_TRDIR) {
+				/*
+				 * Handle a read
+				 */
+				host->buffer = NULL;
+				host->total_length = 0;
 
-			at91_mci_pre_dma_read(host);
-			ier = AT91_MCI_ENDRX /* | AT91_MCI_RXBUFF */;
-		}
-		else {
-			/*
-			 * Handle a write
-			 */
-			host->total_length = block_length * blocks;
-			host->buffer = dma_alloc_coherent(NULL,
-						  host->total_length,
-						  &host->physical_address, GFP_KERNEL);
-
-			at91_mci_sg_to_dma(host, data);
-
-			pr_debug("Transmitting %d bytes\n", host->total_length);
-
-			at91_mci_write(host, ATMEL_PDC_TPR, host->physical_address);
-			at91_mci_write(host, ATMEL_PDC_TCR, host->total_length / 4);
-			ier = AT91_MCI_TXBUFE;
+				at91_mci_pre_dma_read(host);
+				ier = AT91_MCI_ENDRX /* | AT91_MCI_RXBUFF */;
+			}
+			else {
+				/*
+				 * Handle a write
+				 */
+				host->total_length = block_length * blocks;
+				host->buffer = dma_alloc_coherent(NULL,
+						host->total_length,
+						&host->physical_address, GFP_KERNEL);
+
+				at91_mci_sg_to_dma(host, data);
+
+				pr_debug("Transmitting %d bytes\n", host->total_length);
+
+				at91_mci_write(host, ATMEL_PDC_TPR, host->physical_address);
+				at91_mci_write(host, ATMEL_PDC_TCR, host->total_length / 4);
+				ier = AT91_MCI_CMDRDY;
+			}
 		}
 	}
 
@@ -499,24 +527,9 @@ static unsigned int at91_mci_send_comman
 	if (cmdr & AT91_MCI_TRCMD_START) {
 		if (cmdr & AT91_MCI_TRDIR)
 			at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTEN);
-		else
-			at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_TXTEN);
 	}
-	return ier;
-}
 
-/*
- * Wait for a command to complete
- */
-static void at91_mci_process_command(struct at91mci_host *host, struct mmc_command *cmd)
-{
-	unsigned int ier;
-
-	ier = at91_mci_send_command(host, cmd);
-
-	pr_debug("setting ier to %08X\n", ier);
-
-	/* Stop on errors or the required value */
+	/* Enable selected interrupts */
 	at91_mci_write(host, AT91_MCI_IER, AT91_MCI_ERRORS | ier);
 }
 
@@ -527,11 +540,11 @@ static void at91_mci_process_next(struct
 {
 	if (!(host->flags & FL_SENT_COMMAND)) {
 		host->flags |= FL_SENT_COMMAND;
-		at91_mci_process_command(host, host->request->cmd);
+		at91_mci_send_command(host, host->request->cmd);
 	}
 	else if ((!(host->flags & FL_SENT_STOP)) && host->request->stop) {
 		host->flags |= FL_SENT_STOP;
-		at91_mci_process_command(host, host->request->stop);
+		at91_mci_send_command(host, host->request->stop);
 	}
 	else
 		mmc_request_done(host->mmc, host->request);
@@ -698,29 +711,33 @@ static irqreturn_t at91_mci_irq(int irq,
 			at91_mci_handle_transmitted(host);
 		}
 
+		if (int_status & AT91_MCI_ENDRX) {
+			pr_debug("ENDRX\n");
+			at91_mci_post_dma_read(host);
+		}
+
 		if (int_status & AT91_MCI_RXBUFF) {
 			pr_debug("RX buffer full\n");
-			at91_mci_write(host, AT91_MCI_IER, AT91_MCI_CMDRDY);
+			at91_mci_write(host, ATMEL_PDC_PTCR, ATMEL_PDC_RXTDIS | ATMEL_PDC_TXTDIS);
+			at91_mci_write(host, AT91_MCI_IDR, AT91_MCI_RXBUFF | AT91_MCI_ENDRX);
+			completed = 1;
 		}
 
 		if (int_status & AT91_MCI_ENDTX)
 			pr_debug("Transmit has ended\n");
 
-		if (int_status & AT91_MCI_ENDRX) {
-			pr_debug("Receive has ended\n");
-			at91_mci_post_dma_read(host);
-		}
-
 		if (int_status & AT91_MCI_NOTBUSY) {
 			pr_debug("Card is ready\n");
-			at91_mci_write(host, AT91_MCI_IER, AT91_MCI_CMDRDY);
+			completed = 1;
 		}
 
 		if (int_status & AT91_MCI_DTIP)
 			pr_debug("Data transfer in progress\n");
 
-		if (int_status & AT91_MCI_BLKE)
+		if (int_status & AT91_MCI_BLKE) {
 			pr_debug("Block transfer has ended\n");
+			completed = 1;
+		}
 
 		if (int_status & AT91_MCI_TXRDY)
 			pr_debug("Ready to transmit\n");
@@ -730,7 +747,7 @@ static irqreturn_t at91_mci_irq(int irq,
 
 		if (int_status & AT91_MCI_CMDRDY) {
 			pr_debug("Command ready\n");
-			completed = 1;
+			completed = at91_mci_handle_cmdrdy(host);
 		}
 	}
 
@@ -817,7 +834,11 @@ static int __init at91_mci_probe(struct 
 
 	mmc->ops = &at91_mci_ops;
 	mmc->f_min = 375000;
-	mmc->f_max = 25000000;
+	if (cpu_is_at91sam9263())
+		mmc->f_max = 50000000;
+	else
+		mmc->f_max = 25000000;
+
 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
 	mmc->caps = MMC_CAP_BYTEBLOCK | MMC_CAP_MULTIWRITE;
 
@@ -830,11 +851,11 @@ static int __init at91_mci_probe(struct 
 	host->bus_mode = 0;
 	host->board = pdev->dev.platform_data;
 	if (host->board->wire4) {
-#ifdef SUPPORT_4WIRE
-		mmc->caps |= MMC_CAP_4_BIT_DATA;
-#else
-		printk("AT91 MMC: 4 wire bus mode not supported by this driver - using 1 wire\n");
-#endif
+		if (cpu_is_at91sam9260() || cpu_is_at91sam9263())
+			mmc->caps |= MMC_CAP_4_BIT_DATA;
+		else
+			printk("AT91 MMC: 4 wire bus mode not supported"
+				" - using 1 wire\n");
 	}
 
 	/*





^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2007-07-09 16:43 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2007-07-02 12:16 [PATCH] mmc: at91_mci: fix hanging and rework to match flowcharts Nicolas Ferre
2007-07-02 12:45 ` Marc Pignat
2007-07-02 13:32 ` Pierre Ossman
2007-07-09 10:51   ` Pierre Ossman
2007-07-09 12:48   ` Nicolas Ferre
2007-07-02 19:13 ` Mariusz Kozlowski
2007-07-09 12:58 ` Nicolas Ferre
2007-07-09 16:27   ` Pierre Ossman

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