On Tue, 22 Nov 2016 17:09:48 -0800
Jeremy McNicoll <jeremymc@xxxxxxxxxx> wrote:
> On msm8992 it has been observed that IRQs were not getting
> ACK'd correctly when clocked at speeds greater than 400KHz.
>
> Signed-off-by: Jeremy McNicoll <jeremymc@xxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-msm.c | 7 +++++++
> drivers/mmc/host/sdhci.c | 12 ++++++++++--
> drivers/mmc/host/sdhci.h | 2 ++
> 3 files changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 1fcda96..459003c 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -1303,6 +1303,13 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> CORE_VENDOR_SPEC_CAPABILITIES0);
> }
>
> + /* Enable delayed IRQ handling workaround on 8992 */
> + if (core_major == 1 && core_minor == 0x3e) {
> + /* Add 40us delay in interrupt handler when operating
> + * at initialization frequency of 400KHz. */
> + host->quirks2 |= SDHCI_QUIRK2_SLOW_INT_CLR;
> + }
> +
> /* Setup IRQ for handling power/voltage tasks with PMIC */
> msm_host->pwr_irq = platform_get_irq_byname(pdev, "pwr_irq");
> if (msm_host->pwr_irq < 0) {
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 5911f98..c1aae22 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -2703,11 +2703,19 @@ static irqreturn_t sdhci_irq(int irq, void *dev_id)
> result = IRQ_WAKE_THREAD;
> }
>
> - if (intmask & SDHCI_INT_CMD_MASK)
> + if (intmask & SDHCI_INT_CMD_MASK) {
> + if ((host->quirks2 & SDHCI_QUIRK2_SLOW_INT_CLR) && (host->clock <= 400000)) {
> + udelay(40);
> + }
> sdhci_cmd_irq(host, intmask & SDHCI_INT_CMD_MASK);
> + }
>
> - if (intmask & SDHCI_INT_DATA_MASK)
> + if (intmask & SDHCI_INT_DATA_MASK) {
> + if ((host->quirks2 & SDHCI_QUIRK2_SLOW_INT_CLR) && (host->clock <= 400000)) {
> + udelay(40);
> + }
> sdhci_data_irq(host, intmask & SDHCI_INT_DATA_MASK);
> + }
>
> if (intmask & SDHCI_INT_BUS_POWER)
> pr_err("%s: Card is consuming too much power!\n",
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index c055e24..5f8301e 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -24,6 +24,8 @@
> * Controller registers
> */
>
> +#define SDHCI_QUIRK2_SLOW_INT_CLR (1<<5)
IIRC, new quirk isn't allowed now.
Thanks,
Jisheng
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