From c783837bc69dd0f329a441c1704f5a02d01d1bd5 Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 9 Oct 2007 17:07:58 -0400 Subject: [PATCH] pxamci: support arbitrary block size The PXA has two transmit FIFOes, each32 byte deep. when one FIFO is full and the other one has been transmitted, they are automatically swapped and DMA is triggered for another 32 byte burst. However, when there is less than 32 bytes left to send, the FIFO swap has to be done manually. This is required for some SDIO transfers which are not required to be multiples of 32 bytes. A DMA completion interrupt is set for each descriptor which length isn't a multiple of 32 in order to force the FIFO swap. While at it, the DMA interrupt handler has been made a bit more resilient against errors. Signed-off-by: Nicolas Pitre Signed-off-by: Pierre Ossman --- drivers/mmc/host/pxamci.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c index 91e25683b39..657901eecfc 100644 --- a/drivers/mmc/host/pxamci.c +++ b/drivers/mmc/host/pxamci.c @@ -142,6 +142,10 @@ static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data) host->dma_dir); for (i = 0; i < host->dma_len; i++) { + unsigned int length = sg_dma_len(&data->sg[i]); + host->sg_cpu[i].dcmd = dcmd | length; + if (length & 31 && !(data->flags & MMC_DATA_READ)) + host->sg_cpu[i].dcmd |= DCMD_ENDIRQEN; if (data->flags & MMC_DATA_READ) { host->sg_cpu[i].dsadr = host->res->start + MMC_RXFIFO; host->sg_cpu[i].dtadr = sg_dma_address(&data->sg[i]); @@ -149,7 +153,6 @@ static void pxamci_setup_data(struct pxamci_host *host, struct mmc_data *data) host->sg_cpu[i].dsadr = sg_dma_address(&data->sg[i]); host->sg_cpu[i].dtadr = host->res->start + MMC_TXFIFO; } - host->sg_cpu[i].dcmd = dcmd | sg_dma_len(&data->sg[i]); host->sg_cpu[i].ddadr = host->sg_dma + (i + 1) * sizeof(struct pxa_dma_desc); } @@ -414,8 +417,18 @@ static const struct mmc_host_ops pxamci_ops = { static void pxamci_dma_irq(int dma, void *devid) { - printk(KERN_ERR "DMA%d: IRQ???\n", dma); - DCSR(dma) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR; + struct pxamci_host *host = devid; + int dcsr = DCSR(dma); + DCSR(dma) = dcsr & ~DCSR_STOPIRQEN; + + if (dcsr & DCSR_ENDINTR) { + writel(BUF_PART_FULL, host->base + MMC_PRTBUF); + } else { + printk(KERN_ERR "%s: DMA error on channel %d (DCSR=%#x)\n", + mmc_hostname(host->mmc), dma, dcsr); + host->data->error = -EIO; + pxamci_data_done(host, 0); + } } static irqreturn_t pxamci_detect_irq(int irq, void *devid) -- 2.20.1