Hi, all
Expect your advice and any comments.
Thanks.
Regards
Haijun.
> -----Original Message-----
> From: Zhang Haijun-B42677
> Sent: Wednesday, July 17, 2013 6:11 PM
> To: linux-...@vger.kernel.org; linuxppc-dev@lists.ozlabs.org
> Cc: cbouatmai...@gmail.com; c...@laptop.org; Wood Scott-B07421; Fleming
> Andy-AFLEMING; Zhang Haijun-B42677; Zhang Haijun-B42677
> Subject: [PATCH 2/4 V2] mmc: esdhc: workaround for dma err in the last
> system transaction
>
> A-004388: eSDHC DMA might not stop if error occurs on system transaction
>
> eSDHC DMA(SDMA/ADMA) might not stop if an error occurs in the last system
> transaction. It may continue initiating additional transactions until
> software reset for data/all is issued during error recovery. There is not
> any data corruption to the SD data. The IRQSTAT[DMAE] is set when the
> erratum occurs.
> The only conditions under which issues occur are the following:
> 1. SDMA - For SD Write , the error occurs in the last system transaction.
> No issue for SD read
> 2. ADMA
> a. Block count is enabled: For SD write, the error occurs in the last
> system transaction. There is no issue for SD read when block count is
> enabled.
> b. Block count is disabled: Block count is designated by the ADMA
> descriptor table, and the error occurs in the last system transaction
> when ADMA is executing last descriptor line of table.
>
> eSDHC may initiate additional system transactions. There is no data
> integrity issue for case 1 and 2a described below. For case 2b, system
> data might be corrupted.
>
> Workaround: Set eSDHC_SYSCTL[RSTD] when IRQSTAT[DMAE] is set. For cases
> 2a and 2b above, add an extra descriptor line with zero data next to the
> last descriptor line.
>
> Signed-off-by: Haijun Zhang <haijun.zh...@freescale.com>
> ---
> changes for V2:
> - Update the svr version list
>
> drivers/mmc/host/sdhci-of-esdhc.c | 112
> ++++++++++++++++++++++++++++++++++----
> 1 file changed, 102 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-
> of-esdhc.c
> index 15039e2..adfaadd 100644
> --- a/drivers/mmc/host/sdhci-of-esdhc.c
> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
> @@ -21,9 +21,13 @@
> #include <linux/mmc/host.h>
> #include "sdhci-pltfm.h"
> #include "sdhci-esdhc.h"
> +#include <asm/mpc85xx.h>
>
> #define VENDOR_V_22 0x12
> #define VENDOR_V_23 0x13
> +
> +static u32 svr;
> +
> static u32 esdhc_readl(struct sdhci_host *host, int reg) {
> u32 ret;
> @@ -142,6 +146,26 @@ static void esdhc_writeb(struct sdhci_host *host, u8
> val, int reg)
> sdhci_be32bs_writeb(host, val, reg);
> }
>
> +static void esdhc_reset(struct sdhci_host *host, u8 mask) {
> + u32 ier;
> + u32 uninitialized_var(isav);
> +
> + if (host->quirks & SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET)
> + isav = esdhc_readl(host, SDHCI_INT_ENABLE);
> +
> + esdhc_writeb(host, mask, SDHCI_SOFTWARE_RESET);
> + mdelay(100);
> +
> + if (host->quirks & SDHCI_QUIRK_RESTORE_IRQS_AFTER_RESET) {
> + ier = esdhc_readl(host, SDHCI_INT_ENABLE);
> + ier &= ~SDHCI_INT_ALL_MASK;
> + ier |= isav;
> + esdhc_writel(host, ier, SDHCI_INT_ENABLE);
> + esdhc_writel(host, ier, SDHCI_SIGNAL_ENABLE);
> + }
> +}
> +
> /*
> * For Abort or Suspend after Stop at Block Gap, ignore the ADMA
> * error(IRQSTAT[ADMAE]) if both Transfer Complete(IRQSTAT[TC]) @@ -
> 156,25 +180,92 @@ static void esdhci_of_adma_workaround(struct sdhci_host
> *host, u32 intmask)
> dma_addr_t dmastart;
> dma_addr_t dmanow;
>
> - tmp = in_be32(host->ioaddr + SDHCI_SLOT_INT_STATUS);
> + tmp = esdhc_readl(host, SDHCI_SLOT_INT_STATUS);
> tmp = (tmp & SDHCI_VENDOR_VER_MASK) >> SDHCI_VENDOR_VER_SHIFT;
>
> applicable = (intmask & SDHCI_INT_DATA_END) &&
> (intmask & SDHCI_INT_BLK_GAP) &&
> (tmp == VENDOR_V_23);
> - if (!applicable)
> + if (applicable) {
> +
> + esdhc_reset(host, SDHCI_RESET_DATA);
> + host->data->error = 0;
> + dmastart = sg_dma_address(host->data->sg);
> + dmanow = dmastart + host->data->bytes_xfered;
> +
> + /* Force update to the next DMA block boundary. */
> + dmanow = (dmanow & ~(SDHCI_DEFAULT_BOUNDARY_SIZE - 1)) +
> + SDHCI_DEFAULT_BOUNDARY_SIZE;
> + host->data->bytes_xfered = dmanow - dmastart;
> + esdhc_writel(host, dmanow, SDHCI_DMA_ADDRESS);
> +
> return;
> + }
>
> - host->data->error = 0;
> - dmastart = sg_dma_address(host->data->sg);
> - dmanow = dmastart + host->data->bytes_xfered;
> /*
> - * Force update to the next DMA block boundary.
> + * Check for A-004388: eSDHC DMA might not stop if error
> + * occurs on system transaction
> + * Impact list:
> + * T4240-R1.0 B4860-R1.0 P1010-R1.0
> + * P3041-R1.0-R2.0-R1.1 P2041-R1.0-R1.1-R2.0
> + * P5040-R2.0
> */
> - dmanow = (dmanow & ~(SDHCI_DEFAULT_BOUNDARY_SIZE - 1)) +
> - SDHCI_DEFAULT_BOUNDARY_SIZE;
> - host->data->bytes_xfered = dmanow - dmastart;
> - sdhci_writel(host, dmanow, SDHCI_DMA_ADDRESS);
> + if (!(((SVR_SOC_VER(svr) == SVR_T4240) && (SVR_REV(svr) == 0x10))
> ||
> + ((SVR_SOC_VER(svr) == SVR_B4860) && (SVR_REV(svr) == 0x10))
> ||
> + ((SVR_SOC_VER(svr) == SVR_P1010) && (SVR_REV(svr) == 0x10))
> ||
> + ((SVR_SOC_VER(svr) == SVR_P3041) && (SVR_REV(svr) <= 0x20))
> ||
> + ((SVR_SOC_VER(svr) == SVR_P2041) && (SVR_REV(svr) <= 0x20))
> ||
> + ((SVR_SOC_VER(svr) == SVR_P5040) && SVR_REV(svr) == 0x20)))
> + return;
> +
> + esdhc_reset(host, SDHCI_RESET_DATA);
> +
> + if (host->flags & SDHCI_USE_ADMA) {
> + u32 mod, i, offset;
> + u8 *desc;
> + dma_addr_t addr;
> + struct scatterlist *sg;
> + __le32 *dataddr;
> + __le32 *cmdlen;
> +
> + /*
> + * If block count was enabled, in case read transfer there
> + * is no data was corrupted
> + */
> + mod = esdhc_readl(host, SDHCI_TRANSFER_MODE);
> + if ((mod & SDHCI_TRNS_BLK_CNT_EN) &&
> + (host->data->flags & MMC_DATA_READ))
> + host->data->error = 0;
> +
> + BUG_ON(!host->data);
> + desc = host->adma_desc;
> + for_each_sg(host->data->sg, sg, host->sg_count, i) {
> + addr = sg_dma_address(sg);
> + offset = (4 - (addr & 0x3)) & 0x3;
> + if (offset)
> + desc += 8;
> + desc += 8;
> + }
> +
> + /*
> + * Add an extra zero descriptor next to the
> + * terminating descriptor.
> + */
> + desc += 8;
> + WARN_ON((desc - host->adma_desc) > (128 * 2 + 1) * 4);
> +
> + dataddr = (__le32 __force *)(desc + 4);
> + cmdlen = (__le32 __force *)desc;
> +
> + cmdlen[0] = cpu_to_le32(0);
> + dataddr[0] = cpu_to_le32(0);
> + }
> +
> + if ((host->flags & SDHCI_USE_SDMA) &&
> + (host->data->flags & MMC_DATA_READ))
> + host->data->error = 0;
> +
> + return;
> }
>
> static int esdhc_of_enable_dma(struct sdhci_host *host) @@ -299,6 +390,7
> @@ static int sdhci_esdhc_probe(struct platform_device *pdev)
> struct device_node *np;
> int ret;
>
> + svr = mfspr(SPRN_SVR);
> host = sdhci_pltfm_init(pdev, &sdhci_esdhc_pdata, 0);
> if (IS_ERR(host))
> return PTR_ERR(host);
> --
> 1.8.0
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