Re: [PATCH 1/5] mmc: sdhci-msm: fix issue with power irq
From: Adrian Hunter
Date: Thu Aug 24 2017 - 03:47:27 EST
On 18/08/17 08:19, Vijay Viswanath wrote:
> From: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
>
> SDCC controller reset (SW_RST) during probe may trigger power irq if
> previous status of PWRCTL was either BUS_ON or IO_HIGH_V. So before we
> enable the power irq interrupt in GIC (by registering the interrupt
> handler), we need to ensure that any pending power irq interrupt status
> is acknowledged otherwise power irq interrupt handler would be fired
> prematurely.
>
> Signed-off-by: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
> Signed-off-by: Vijay Viswanath <vviswana@xxxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-msm.c | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 9d601dc..0957199 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -1128,6 +1128,7 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> u16 host_version, core_minor;
> u32 core_version, config;
> u8 core_major;
> + u32 irq_status, irq_ctl;
>
> host = sdhci_pltfm_init(pdev, &sdhci_msm_pdata, sizeof(*msm_host));
> if (IS_ERR(host))
> @@ -1250,6 +1251,28 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> CORE_VENDOR_SPEC_CAPABILITIES0);
> }
>
> + /*
> + * Power on reset state may trigger power irq if previous status of
> + * PWRCTL was either BUS_ON or IO_HIGH_V. So before enabling pwr irq
> + * interrupt in GIC, any pending power irq interrupt should be
> + * acknowledged. Otherwise power irq interrupt handler would be
> + * fired prematurely.
> + */
> +
> + irq_status = readl_relaxed(msm_host->core_mem + CORE_PWRCTL_STATUS);
> + writel_relaxed(irq_status, msm_host->core_mem + CORE_PWRCTL_CLEAR);
> + irq_ctl = readl_relaxed(msm_host->core_mem + CORE_PWRCTL_CTL);
> + if (irq_status & (CORE_PWRCTL_BUS_ON | CORE_PWRCTL_BUS_OFF))
> + irq_ctl |= CORE_PWRCTL_BUS_SUCCESS;
> + if (irq_status & (CORE_PWRCTL_IO_HIGH | CORE_PWRCTL_IO_LOW))
> + irq_ctl |= CORE_PWRCTL_IO_SUCCESS;
> + writel_relaxed(irq_ctl, msm_host->core_mem + CORE_PWRCTL_CTL);
This looks a lot like sdhci_msm_voltage_switch(). Can clearing the
interrupt be a common function?
> + /*
> + * Ensure that above writes are propogated before interrupt enablement
> + * in GIC.
> + */
> + mb();
> +
> /* 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) {
> @@ -1259,6 +1282,9 @@ static int sdhci_msm_probe(struct platform_device *pdev)
> goto clk_disable;
> }
>
> + /* Enable pwr irq interrupts */
> + writel_relaxed(INT_MASK, msm_host->core_mem + CORE_PWRCTL_MASK);
> +
> ret = devm_request_threaded_irq(&pdev->dev, msm_host->pwr_irq, NULL,
> sdhci_msm_pwr_irq, IRQF_ONESHOT,
> dev_name(&pdev->dev), host);
>