mmc: sdhci: improve ADMA error reporting

commit d1c536e3 upstream.

ADMA errors are potentially data corrupting events; although we print
the register state, we do not usefully print the ADMA descriptors.
Worse than that, we print them by referencing their virtual address
which is meaningless when the register state gives us the DMA address
of the failing descriptor.

Print the ADMA descriptors giving their DMA addresses rather than their
virtual addresses, and print them using SDHCI_DUMP() rather than DBG().

We also do not show the correct value of the interrupt status register;
the register dump shows the current value, after we have cleared the
pending interrupts we are going to service.  What is more useful is to
print the interrupts that _were_ pending at the time the ADMA error was
encountered.  Fix that too.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/mmc/host/sdhci.c

@@ -2720,6 +2720,7 @@ static void sdhci_cmd_irq(struct sdhci_host *host, u32 intmask, u32 *intmask_p)
 static void sdhci_adma_show_error(struct sdhci_host *host)
 {
 	void *desc = host->adma_table;
+	dma_addr_t dma = host->adma_addr;
 
 	sdhci_dumpregs(host);
 
@@ -2727,18 +2728,21 @@ static void sdhci_adma_show_error(struct sdhci_host *host)
 		struct sdhci_adma2_64_desc *dma_desc = desc;
 
 		if (host->flags & SDHCI_USE_64_BIT_DMA)
-			DBG("%p: DMA 0x%08x%08x, LEN 0x%04x, Attr=0x%02x\n",
-			    desc, le32_to_cpu(dma_desc->addr_hi),
+			SDHCI_DUMP("%08llx: DMA 0x%08x%08x, LEN 0x%04x, Attr=0x%02x\n",
+			    (unsigned long long)dma,
+			    le32_to_cpu(dma_desc->addr_hi),
 			    le32_to_cpu(dma_desc->addr_lo),
 			    le16_to_cpu(dma_desc->len),
 			    le16_to_cpu(dma_desc->cmd));
 		else
-			DBG("%p: DMA 0x%08x, LEN 0x%04x, Attr=0x%02x\n",
-			    desc, le32_to_cpu(dma_desc->addr_lo),
+			SDHCI_DUMP("%08llx: DMA 0x%08x, LEN 0x%04x, Attr=0x%02x\n",
+			    (unsigned long long)dma,
+			    le32_to_cpu(dma_desc->addr_lo),
 			    le16_to_cpu(dma_desc->len),
 			    le16_to_cpu(dma_desc->cmd));
 
 		desc += host->desc_sz;
+		dma += host->desc_sz;
 
 		if (dma_desc->cmd & cpu_to_le16(ADMA2_END))
 			break;
@@ -2814,7 +2818,8 @@ static void sdhci_data_irq(struct sdhci_host *host, u32 intmask)
 			!= MMC_BUS_TEST_R)
 		host->data->error = -EILSEQ;
 	else if (intmask & SDHCI_INT_ADMA_ERROR) {
-		pr_err("%s: ADMA error\n", mmc_hostname(host->mmc));
+		pr_err("%s: ADMA error: 0x%08x\n", mmc_hostname(host->mmc),
+		       intmask);
 		sdhci_adma_show_error(host);
 		host->data->error = -EIO;
 		if (host->ops->adma_workaround)