On Wed, Nov 13, 2013 at 08:54:58AM +0800, Aaron Lu wrote:
> On 11/12/2013 05:27 PM, Jackey Shen wrote:
> > On Tue, Nov 12, 2013 at 03:44:40PM +0800, Aaron Lu wrote:
> >> On 11/12/2013 02:56 PM, Jackey Shen wrote:
> >>> Enable MSI support in sdhci-pci driver and provide the mechanism
> >>> to fall back to Legacy Pin-based Interrupt if MSI register fails.
> >>>
> >>> Tested with SD cards on AMD platform.
> >>>
> >>
> >> ->
> >>
> >>> Change from V1:
> >>> - implement this PCI MSI feature in sdhci-pci.c instead of sdhci.c
> >>
> >> Such words can be placed under the --- below so that it will not appear
> >> in git log.
> >>
> >>>
> >>> Signed-off-by: Jackey Shen <Jackey.Shen@xxxxxxx>
> >>> Reviewed-by: Huang Rui <ray.huang@xxxxxxx>
> >>> ---
> >>
> >> ->
> >> Put change related info Here.
> >
> > OK. I will update my patch.
> >
> >>
> >>> drivers/mmc/host/Kconfig | 11 +++++++++
> >>> drivers/mmc/host/sdhci-pci.c | 58 ++++++++++++++++++++++++++++++++++++++++++++
> >>> drivers/mmc/host/sdhci.c | 42 ++++++++++++++++++++++++++------
> >>> drivers/mmc/host/sdhci.h | 2 ++
> >>> include/linux/mmc/sdhci.h | 2 ++
> >>> 5 files changed, 107 insertions(+), 8 deletions(-)
> >>>
> >>> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> >>> index 7fc5099..a56cf27 100644
> >>> --- a/drivers/mmc/host/Kconfig
> >>> +++ b/drivers/mmc/host/Kconfig
> >>> @@ -68,6 +68,17 @@ config MMC_SDHCI_PCI
> >>>
> >>> If unsure, say N.
> >>>
> >>> +config MMC_SDHCI_PCI_MSI
> >>> + bool "SDHCI support with MSI on PCI bus"
> >>> + depends on MMC_SDHCI_PCI && PCI_MSI
> >>> + help
> >>> + This enables PCI MSI (Message Signaled Interrupts) for Secure
> >>> + Digital Host Controller Interface.
> >>> +
> >>> + If you have a controller with this capability, say Y or M here.
> >>> +
> >>> + If unsure, say N.
> >>> +
> >>> config MMC_RICOH_MMC
> >>> bool "Ricoh MMC Controller Disabler"
> >>> depends on MMC_SDHCI_PCI
> >>> diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c
> >>> index 8f75381..2ca29c0 100644
> >>> --- a/drivers/mmc/host/sdhci-pci.c
> >>> +++ b/drivers/mmc/host/sdhci-pci.c
> >>> @@ -1143,10 +1143,68 @@ static void sdhci_pci_hw_reset(struct sdhci_host *host)
> >>> slot->hw_reset(host);
> >>> }
> >>>
> >>> +#ifdef CONFIG_MMC_SDHCI_PCI_MSI
> >>> +static int sdhci_pci_setup_msi(struct sdhci_host *host, irq_handler_t handler)
> >>> +{
> >>> + int ret;
> >>> + struct pci_dev *pdev = to_pci_dev(host->mmc->parent);
> >>> +
> >>> + host->msi_enabled = false;
> >>> +
> >>> + ret = pci_enable_msi(pdev);
> >>> + if (ret) {
> >>> + pr_warn("%s: Failed to allocate MSI entry\n",
> >>> + mmc_hostname(host->mmc));
> >>> + return ret;
> >>> + }
> >>> +
> >>> + ret = request_irq(pdev->irq, handler, 0,
> >>> + mmc_hostname(host->mmc), host);
> >>> + if (ret) {
> >>> + pr_warn("%s: Failed to request MSI IRQ %d: %d\n",
> >>> + mmc_hostname(host->mmc), pdev->irq, ret);
> >>> + pci_disable_msi(pdev);
> >>> + return ret;
> >>> + }
> >>> +
> >>> + host->irq = pdev->irq;
> >>> + host->msi_enabled = true;
> >>> + return ret;
> >>> +}
> >>
> >> What about we only call pci_enable_msi in sdhci-pci.c and then assign
> >> host->irq appropriately before calling sdhci_add_host, will that work?
> >> The only difference would be, request_irq will have SHARED flag, but I
> >> suppose that's not a problem.
> >>
> > There are 2 points for this part:
> > 1. fall back to legacy interrupt right after MSI request fails;
>
> If we call pci_enable_msi somewhere in sdhci_pci_probe_slot, then if it
> failed, we can also fall back I suppose?
>
Yes, it is.
Also, sdhci_pci_disable_msi should be kept since pci_disable_msi is
pci bus releted and better not used in sdhci.c.
So, enable msi and disable msi are symmetric in style.
What's your opinion?
> > 2. prompt user more information about where error/warning occur.
> >
> >>> +
> >>> +static int sdhci_pci_enable_msi(struct sdhci_host *host, irq_handler_t handler)
> >>> +{
> >>> + return sdhci_pci_setup_msi(host, handler);
> >>> +}
> >>> +
> >>> +static void sdhci_pci_disable_msi(struct sdhci_host *host)
> >>> +{
> >>> + struct pci_dev *pdev = to_pci_dev(host->mmc->parent);
> >>> +
> >>> + if (host->msi_enabled) {
> >>> + pci_disable_msi(pdev);
> >>> + host->msi_enabled = false;
> >>> + }
> >>> +}
> >>> +
> >>> +#else
> >>> +
> >>> +static int sdhci_pci_enable_msi(struct sdhci_host *host, irq_handler_t handler)
> >>> +{
> >>> + return 0;
> >>> +}
> >>> +
> >>> +static void sdhci_pci_disable_msi(struct sdhci_host *host)
> >>> +{
> >>> +}
> >>> +#endif /* CONFIG_MMC_SDHCI_PCI_MSI */
> >>> +
> >>> static const struct sdhci_ops sdhci_pci_ops = {
> >>> .enable_dma = sdhci_pci_enable_dma,
> >>> .platform_bus_width = sdhci_pci_bus_width,
> >>> .hw_reset = sdhci_pci_hw_reset,
> >>> + .enable_msi = sdhci_pci_enable_msi,
> >>> + .disable_msi = sdhci_pci_disable_msi,
> >>> };
> >>>
> >>> /*****************************************************************************\
> >>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> >>> index 6785fb1..4c2a1ac 100644
> >>> --- a/drivers/mmc/host/sdhci.c
> >>> +++ b/drivers/mmc/host/sdhci.c
> >>> @@ -2554,6 +2554,31 @@ void sdhci_disable_irq_wakeups(struct sdhci_host *host)
> >>> }
> >>> EXPORT_SYMBOL_GPL(sdhci_disable_irq_wakeups);
> >>>
> >>> +static int sdhci_request_irq(struct sdhci_host *host)
> >>> +{
> >>> + int ret = 0;
> >>> +
> >>> + /* try to enable MSI */
> >>> + if (host->ops->enable_msi) {
> >>> + ret = host->ops->enable_msi(host, sdhci_irq);
> >>> + if (ret)
> >>> + pr_warn("%s: Fall back to Pin-based Interrupt: %d\n",
> >>> + mmc_hostname(host->mmc), ret);
> >>> + }
> >>> +
> >>> + if (!host->msi_enabled) {
> >>> + /* fall back to legacy pin-based interrupt */
> >>> + ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
> >>> + mmc_hostname(host->mmc), host);
> >>> + if (ret) {
> >>> + pr_err("%s: Failed to request IRQ %d: %d\n",
> >>> + mmc_hostname(host->mmc), host->irq, ret);
> >>> + return ret;
> >>> + }
> >>> + }
> >>> +
> >>> + return ret;
> >>> +}
> >>> int sdhci_suspend_host(struct sdhci_host *host)
> >>> {
> >>> if (host->ops->platform_suspend)
> >>> @@ -2570,6 +2595,8 @@ int sdhci_suspend_host(struct sdhci_host *host)
> >>> if (!device_may_wakeup(mmc_dev(host->mmc))) {
> >>> sdhci_mask_irqs(host, SDHCI_INT_ALL_MASK);
> >>> free_irq(host->irq, host);
> >>> + if (host->ops->disable_msi)
> >>> + host->ops->disable_msi(host);
> >>
> >> What would happen if we do not disable/enable msi in suspend/resume host?
> >> We have already masked all irqs with sdhci_mask_irqs anyway.
> >>
> > We should also remove request|free_irq at the same time, right?
> > I will do some tests.
>
> The comments above free_irq says:
>
> * on the card it drives before calling this function. The function
> * does not return until any executing interrupts for this IRQ
> * have completed.
>
> It feels like a guard for the interrupt handler: after we call free_irq,
> we are sure no interrupt hander is running(and since we have masked irq,
> no more interrupt will occur either), so I suggest we keep it.
>
I did some tests according to your suggestion and it works fine.
Thanks,
Jackey
> Thanks,
> Aaron
>
> >>> } else {
> >>> sdhci_enable_irq_wakeups(host);
> >>> enable_irq_wake(host->irq);
> >>> @@ -2589,8 +2616,7 @@ int sdhci_resume_host(struct sdhci_host *host)
> >>> }
> >>>
> >>> if (!device_may_wakeup(mmc_dev(host->mmc))) {
> >>> - ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
> >>> - mmc_hostname(host->mmc), host);
> >>> + ret = sdhci_request_irq(host);
> >>> if (ret)
> >>> return ret;
> >>> } else {
> >>> @@ -3212,13 +3238,9 @@ int sdhci_add_host(struct sdhci_host *host)
> >>>
> >>> sdhci_init(host, 0);
> >>>
> >>> - ret = request_irq(host->irq, sdhci_irq, IRQF_SHARED,
> >>> - mmc_hostname(mmc), host);
> >>> - if (ret) {
> >>> - pr_err("%s: Failed to request IRQ %d: %d\n",
> >>> - mmc_hostname(mmc), host->irq, ret);
> >>> + ret = sdhci_request_irq(host);
> >>> + if (ret)
> >>> goto untasklet;
> >>> - }
> >>>
> >>> #ifdef CONFIG_MMC_DEBUG
> >>> sdhci_dumpregs(host);
> >>> @@ -3258,6 +3280,8 @@ reset:
> >>> sdhci_reset(host, SDHCI_RESET_ALL);
> >>> sdhci_mask_irqs(host, SDHCI_INT_ALL_MASK);
> >>> free_irq(host->irq, host);
> >>> + if (host->ops->disable_msi)
> >>> + host->ops->disable_msi(host);
> >>> #endif
> >>> untasklet:
> >>> tasklet_kill(&host->card_tasklet);
> >>> @@ -3301,6 +3325,8 @@ void sdhci_remove_host(struct sdhci_host *host, int dead)
> >>>
> >>> sdhci_mask_irqs(host, SDHCI_INT_ALL_MASK);
> >>> free_irq(host->irq, host);
> >>> + if (host->ops->disable_msi)
> >>> + host->ops->disable_msi(host);
> >>>
> >>> del_timer_sync(&host->timer);
> >>>
> >>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> >>> index 0a3ed01..cbee843 100644
> >>> --- a/drivers/mmc/host/sdhci.h
> >>> +++ b/drivers/mmc/host/sdhci.h
> >>> @@ -296,6 +296,8 @@ struct sdhci_ops {
> >>> void (*adma_workaround)(struct sdhci_host *host, u32 intmask);
> >>> void (*platform_init)(struct sdhci_host *host);
> >>> void (*card_event)(struct sdhci_host *host);
> >>> + int (*enable_msi)(struct sdhci_host *host, irq_handler_t handler);
> >>> + void (*disable_msi)(struct sdhci_host *host);
> >>> };
> >>>
> >>> #ifdef CONFIG_MMC_SDHCI_IO_ACCESSORS
> >>> diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
> >>> index 3e781b8..3812479 100644
> >>> --- a/include/linux/mmc/sdhci.h
> >>> +++ b/include/linux/mmc/sdhci.h
> >>> @@ -99,6 +99,8 @@ struct sdhci_host {
> >>> /* Controller has a non-standard host control register */
> >>> #define SDHCI_QUIRK2_BROKEN_HOST_CONTROL (1<<5)
> >>>
> >>> + bool msi_enabled; /* SD host controller with PCI MSI enabled */
> >>> +
> >>> int irq; /* Device IRQ */
> >>> void __iomem *ioaddr; /* Mapped address */
> >>>
> >>>
> >>
> >> --
> >> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> >> the body of a message to majordomo@xxxxxxxxxxxxxxx
> >> More majordomo info at http://vger.kernel.org/majordomo-info.html
> >>
> >
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
