On 7 June 2013 23:49, Tony Lindgren <tony@xxxxxxxxxxx> wrote:
> From: Andreas Fenkart <andreas.fenkart@xxxxxxxxxxxxxxxxxxx>
>
> Without functional clock the omap_hsmmc module can't forward SDIO IRQs to
> the system. This patch reconfigures dat1 line as a gpio while the fclk is
> off. When the fclk is present it uses the standard SDIO IRQ detection of
> the module.
>
> The gpio irq is managed via the 'disable_depth' ref counter of the irq
> subsystem, this driver simply calls enable_irq/disable_irq when needed.
>
> sdio irq sdio irq
> unmasked masked
> -----------------------------------------
> runtime default | 1 | 2
> runtime suspend | 0 | 1
>
> irq disable depth
>
>
> only when sdio irq is enabled AND the module is idle, the reference
> count drops to zero and the gpio irq is effectively armed.
>
> Patch was tested on AM335x/Stream800. Test setup was two modules
> with sdio wifi cards. Modules where connected to a dual-band AP, each
> module using a different band. One of module was running iperf as server
> the other as client connecting to the server in a while true loop. Test
> was running for 4+ weeks. There were about 60 Mio. suspend/resume
> transitions. Test was shut down regularly.
>
> Cc: Andreas Fenkart <afenkart@xxxxxxxxx>
> Cc: Balaji T K <balajitk@xxxxxx>
> Signed-off-by: Andreas Fenkart <andreas.fenkart@xxxxxxxxxxxxxxxxxxx>
> Reviewed-by: Grant Likely <grant.likely@xxxxxxxxxxxx>
> [tony@xxxxxxxxxxx: updated and separated out pin muxing]
> Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx>
> ---
> .../devicetree/bindings/mmc/ti-omap-hsmmc.txt | 42 ++++
> drivers/mmc/host/omap_hsmmc.c | 206 +++++++++++++++++++-
> include/linux/platform_data/mmc-omap.h | 4
> 3 files changed, 239 insertions(+), 13 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> index ed271fc..5a3df37 100644
> --- a/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> +++ b/Documentation/devicetree/bindings/mmc/ti-omap-hsmmc.txt
> @@ -20,6 +20,29 @@ ti,dual-volt: boolean, supports dual voltage cards
> ti,non-removable: non-removable slot (like eMMC)
> ti,needs-special-reset: Requires a special softreset sequence
> ti,needs-special-hs-handling: HSMMC IP needs special setting for handling High Speed
> +ti,cirq-gpio: When omap_hsmmc module is suspended, its functional
> +clock is turned off. Without fclk it can't forward SDIO IRQs to the
> +system. For that to happen, it needs to tell the PRCM to restore
> +its fclk, which is done through the swakeup line.
> +
> + ------
> + | PRCM |
> + ------
> + | ^
> + fclk | | swakeup
> + v |
> + ------- ------
> + <-- IRQ -- | hsmmc | <-- CIRQ -- | card |
> + ------- ------
> +
> +The problem is, that on the AM335x family the swakeup line is
> +missing, it has not been routed from the module to the PRCM.
> +The way to work around this, is to reconfigure the dat1 line as a
> +GPIO upon suspend. Beyond this option you also need to set named
> +states "default" and "idle "in the .dts file for the pins, using
> +pinctrl-single.c. The MMC driver will then then toggle between
> +default and idle during the runtime.
> +
>
> Example:
> mmc1: mmc@0x4809c000 {
> @@ -31,3 +54,22 @@ Example:
> vmmc-supply = <&vmmc>; /* phandle to regulator node */
> ti,non-removable;
> };
> +
> +[am335x with with gpio for sdio irq]
> +
> + mmc1_cirq_pin: pinmux_cirq_pin {
> + pinctrl-single,pins = <
> + 0x0f8 0x3f /* MMC0_DAT1 as GPIO2_28 */
> + >;
> + };
> +
> + mmc1: mmc@48060000 {
> + pinctrl-names = "default", "idle";
> + pinctrl-0 = <&mmc1_pins>;
> + pinctrl-1 = <&mmc1_cirq_pin>;
> + ti,cirq-gpio = <&gpio3 28 0>;
> + ti,non-removable;
> + bus-width = <4>;
> + vmmc-supply = <&ldo2_reg>;
> + vmmc_aux-supply = <&vmmc>;
> + };
> diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
> index 478849b..7e28501 100644
> --- a/drivers/mmc/host/omap_hsmmc.c
> +++ b/drivers/mmc/host/omap_hsmmc.c
> @@ -22,6 +22,7 @@
> #include <linux/dmaengine.h>
> #include <linux/seq_file.h>
> #include <linux/interrupt.h>
> +#include <linux/irq.h>
> #include <linux/delay.h>
> #include <linux/dma-mapping.h>
> #include <linux/platform_device.h>
> @@ -102,6 +103,7 @@
> #define TC_EN (1 << 1)
> #define BWR_EN (1 << 4)
> #define BRR_EN (1 << 5)
> +#define CIRQ_EN (1 << 8)
> #define ERR_EN (1 << 15)
> #define CTO_EN (1 << 16)
> #define CCRC_EN (1 << 17)
> @@ -182,9 +184,19 @@ struct omap_hsmmc_host {
> int use_reg;
> int req_in_progress;
> struct omap_hsmmc_next next_data;
> + bool sdio_irq_en;
> + bool active_pinmux;
> struct omap_mmc_platform_data *pdata;
> };
>
> +static irqreturn_t omap_hsmmc_cirq(int irq, void *dev_id)
> +{
> + struct omap_hsmmc_host *host = dev_id;
> +
> + mmc_signal_sdio_irq(host->mmc);
> + return IRQ_HANDLED;
> +}
> +
> static int omap_hsmmc_card_detect(struct device *dev, int slot)
> {
> struct omap_hsmmc_host *host = dev_get_drvdata(dev);
> @@ -419,10 +431,31 @@ static int omap_hsmmc_gpio_init(struct omap_mmc_platform_data *pdata)
> } else
> pdata->slots[0].gpio_wp = -EINVAL;
>
> + if (pdata->slots[0].gpio_cirq > 0 &&
> + gpio_is_valid(pdata->slots[0].gpio_cirq)) {
> + pdata->slots[0].sdio_irq =
> + gpio_to_irq(pdata->slots[0].gpio_cirq);
> +
> + ret = gpio_request(pdata->slots[0].gpio_cirq, "sdio_cirq");
> + if (ret)
> + goto err_free_ro;
> + ret = gpio_direction_input(pdata->slots[0].gpio_cirq);
> + if (ret)
> + goto err_free_cirq;
> +
> + } else {
> + pdata->slots[0].gpio_cirq = -EINVAL;
> + }
> +
> +
> return 0;
>
> +err_free_cirq:
> + gpio_free(pdata->slots[0].gpio_cirq);
> +err_free_ro:
> + if (gpio_is_valid(pdata->slots[0].gpio_wp))
> err_free_wp:
> - gpio_free(pdata->slots[0].gpio_wp);
> + gpio_free(pdata->slots[0].gpio_wp);
> err_free_cd:
> if (gpio_is_valid(pdata->slots[0].switch_pin))
> err_free_sp:
> @@ -436,6 +469,8 @@ static void omap_hsmmc_gpio_free(struct omap_mmc_platform_data *pdata)
> gpio_free(pdata->slots[0].gpio_wp);
> if (gpio_is_valid(pdata->slots[0].switch_pin))
> gpio_free(pdata->slots[0].switch_pin);
> + if (gpio_is_valid(pdata->slots[0].gpio_cirq))
> + gpio_free(pdata->slots[0].gpio_cirq);
> }
>
> /*
> @@ -461,27 +496,46 @@ static void omap_hsmmc_stop_clock(struct omap_hsmmc_host *host)
> static void omap_hsmmc_enable_irq(struct omap_hsmmc_host *host,
> struct mmc_command *cmd)
> {
> - unsigned int irq_mask;
> + u32 irq_mask = INT_EN_MASK;
> + unsigned long flags;
>
> if (host->use_dma)
> - irq_mask = INT_EN_MASK & ~(BRR_EN | BWR_EN);
> - else
> - irq_mask = INT_EN_MASK;
> + irq_mask &= ~(BRR_EN | BWR_EN);
>
> /* Disable timeout for erases */
> if (cmd->opcode == MMC_ERASE)
> irq_mask &= ~DTO_EN;
>
> + spin_lock_irqsave(&host->irq_lock, flags);
> +
> OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
> OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
> +
> + /* latch pending CIRQ, but don't signal */
> + if (host->sdio_irq_en)
> + irq_mask |= CIRQ_EN;
> +
> OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
> +
> + spin_unlock_irqrestore(&host->irq_lock, flags);
> }
>
> static void omap_hsmmc_disable_irq(struct omap_hsmmc_host *host)
> {
> - OMAP_HSMMC_WRITE(host->base, ISE, 0);
> - OMAP_HSMMC_WRITE(host->base, IE, 0);
> + u32 irq_mask = 0;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&host->irq_lock, flags);
> +
> + /* no transfer running, need to signal cirq if */
> + if (host->sdio_irq_en)
> + irq_mask |= CIRQ_EN;
> +
> + OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
> + OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
> OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
> +
> + spin_unlock_irqrestore(&host->irq_lock, flags);
> }
>
> /* Calculate divisor for the given clock frequency */
> @@ -1037,8 +1091,12 @@ static irqreturn_t omap_hsmmc_irq(int irq, void *dev_id)
> int status;
>
> status = OMAP_HSMMC_READ(host->base, STAT);
> - while (status & INT_EN_MASK && host->req_in_progress) {
> - omap_hsmmc_do_irq(host, status);
> + while (status & (INT_EN_MASK | CIRQ_EN)) {
> + if (host->req_in_progress)
> + omap_hsmmc_do_irq(host, status);
> +
> + if (status & CIRQ_EN)
> + mmc_signal_sdio_irq(host->mmc);
>
> /* Flush posted write */
> OMAP_HSMMC_WRITE(host->base, STAT, status);
> @@ -1554,6 +1612,51 @@ static void omap_hsmmc_init_card(struct mmc_host *mmc, struct mmc_card *card)
> mmc_slot(host).init_card(card);
> }
>
> +static void omap_hsmmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
> +{
> + struct omap_hsmmc_host *host = mmc_priv(mmc);
> + u32 irq_mask;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&host->irq_lock, flags);
> +
> + if (host->sdio_irq_en == enable) {
> + dev_dbg(host->dev, "en/disable:%d already set", enable);
> + spin_unlock_irqrestore(&host->irq_lock, flags);
> + return;
> + }
> +
Hi Tony/Andreas,
I belive a "pm_runtime_get_sync" would be needed here, outside the
spinlock ofcourse. Before returning from this function, obviusly
return the references by a pm_runtime_put* in some form.
Then you will be able to remove the "active_pinmux" variable entirely,
since you know the runtime callbacks is the only place were you need
to handle the gpio irq enable|disable.
Kind regards
Ulf Hansson
> + host->sdio_irq_en = (enable != 0) ? true : false;
> +
> + if (host->active_pinmux) { /* register access fails without fclk */
> + irq_mask = OMAP_HSMMC_READ(host->base, ISE);
> + if (enable)
> + irq_mask |= CIRQ_EN;
> + else
> + irq_mask &= ~CIRQ_EN;
> + OMAP_HSMMC_WRITE(host->base, IE, irq_mask);
> +
> + if (!host->req_in_progress)
> + OMAP_HSMMC_WRITE(host->base, ISE, irq_mask);
> +
> + /*
> + * evtl. need to flush posted write
> + * OMAP_HSMMC_READ(host->base, IE);
> + */
> + }
> +
> + if ((mmc_slot(host).sdio_irq)) {
> + if (enable) {
> + enable_irq(mmc_slot(host).sdio_irq);
> + } else {
> + /* _nosync, see mmc_signal_sdio_irq */
> + disable_irq_nosync(mmc_slot(host).sdio_irq);
> + }
> + }
> +
> + spin_unlock_irqrestore(&host->irq_lock, flags);
> +}
> +
> static void omap_hsmmc_conf_bus_power(struct omap_hsmmc_host *host)
> {
> u32 hctl, capa, value;
> @@ -1606,7 +1709,7 @@ static const struct mmc_host_ops omap_hsmmc_ops = {
> .get_cd = omap_hsmmc_get_cd,
> .get_ro = omap_hsmmc_get_ro,
> .init_card = omap_hsmmc_init_card,
> - /* NYET -- enable_sdio_irq */
> + .enable_sdio_irq = omap_hsmmc_enable_sdio_irq,
> };
>
> #ifdef CONFIG_DEBUG_FS
> @@ -1710,6 +1813,7 @@ static struct omap_mmc_platform_data *of_get_hsmmc_pdata(struct device *dev)
> pdata->nr_slots = 1;
> pdata->slots[0].switch_pin = cd_gpio;
> pdata->slots[0].gpio_wp = wp_gpio;
> + pdata->slots[0].gpio_cirq = of_get_named_gpio(np, "ti,cirq-gpio", 0);
>
> if (of_find_property(np, "ti,non-removable", NULL)) {
> pdata->slots[0].nonremovable = true;
> @@ -1802,6 +1906,8 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
> host->dma_ch = -1;
> host->irq = irq;
> host->slot_id = 0;
> + host->sdio_irq_en = false;
> + host->active_pinmux = true;
> host->mapbase = res->start + pdata->reg_offset;
> host->base = ioremap(host->mapbase, SZ_4K);
> host->power_mode = MMC_POWER_OFF;
> @@ -1955,6 +2061,29 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
> pdata->resume = omap_hsmmc_resume_cdirq;
> }
>
> + if ((mmc_slot(host).sdio_irq)) {
> + /* prevent auto-enabling of IRQ */
> + irq_set_status_flags(mmc_slot(host).sdio_irq, IRQ_NOAUTOEN);
> + ret = request_irq(mmc_slot(host).sdio_irq, omap_hsmmc_cirq,
> + IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> + mmc_hostname(mmc), host);
> + if (ret) {
> + dev_dbg(mmc_dev(host->mmc),
> + "Unable to grab MMC SDIO IRQ\n");
> + goto err_irq_sdio;
> + }
> +
> + /*
> + * sdio_irq is managed with ref count
> + * - omap_hsmmc_enable_sdio_irq will +1/-1
> + * - pm_suspend/pm_resume will +1/-1
> + * only when sdio irq is enabled AND module will go to runtime
> + * suspend the ref count will drop to zero and the irq is
> + * effectively enabled. starting with ref count equal 2
> + */
> + disable_irq(mmc_slot(host).sdio_irq);
> + }
> +
> omap_hsmmc_disable_irq(host);
>
> pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
> @@ -1962,6 +2091,19 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
> dev_warn(&pdev->dev,
> "pins are not configured from the driver\n");
>
> + /*
> + * For now, only support SDIO interrupt if we are doing
> + * muxing of dat1 when booted with DT. This is because the
> + * supposedly the wake-up events for CTPL don't work from deeper
> + * idle states. And we don't want to add new legacy mux platform
> + * init code callbacks any longer as we are moving to DT based
> + * booting anyways.
> + */
> + if (match) {
> + if (!IS_ERR(pinctrl) && mmc_slot(host).sdio_irq)
> + mmc->caps |= MMC_CAP_SDIO_IRQ;
> + }
> +
> omap_hsmmc_protect_card(host);
>
> mmc_add_host(mmc);
> @@ -1986,6 +2128,9 @@ static int omap_hsmmc_probe(struct platform_device *pdev)
>
> err_slot_name:
> mmc_remove_host(mmc);
> + if ((mmc_slot(host).sdio_irq))
> + free_irq(mmc_slot(host).sdio_irq, host);
> +err_irq_sdio:
> free_irq(mmc_slot(host).card_detect_irq, host);
> err_irq_cd:
> if (host->use_reg)
> @@ -2032,9 +2177,10 @@ static int omap_hsmmc_remove(struct platform_device *pdev)
> if (host->pdata->cleanup)
> host->pdata->cleanup(&pdev->dev);
> free_irq(host->irq, host);
> + if ((mmc_slot(host).sdio_irq))
> + free_irq(mmc_slot(host).sdio_irq, host);
> if (mmc_slot(host).card_detect_irq)
> free_irq(mmc_slot(host).card_detect_irq, host);
> -
> if (host->tx_chan)
> dma_release_channel(host->tx_chan);
> if (host->rx_chan)
> @@ -2157,23 +2303,57 @@ static int omap_hsmmc_resume(struct device *dev)
> static int omap_hsmmc_runtime_suspend(struct device *dev)
> {
> struct omap_hsmmc_host *host;
> + struct mmc_host *mmc;
> + unsigned long flags;
> + int ret = 0;
>
> host = platform_get_drvdata(to_platform_device(dev));
> + mmc = host->mmc;
> omap_hsmmc_context_save(host);
> dev_dbg(dev, "disabled\n");
>
> - return 0;
> + if (mmc->caps & MMC_CAP_SDIO_IRQ) {
> + spin_lock_irqsave(&host->irq_lock, flags);
> + host->active_pinmux = false;
> + OMAP_HSMMC_WRITE(host->base, ISE, 0);
> + OMAP_HSMMC_WRITE(host->base, IE, 0);
> + OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
> + spin_unlock_irqrestore(&host->irq_lock, flags);
> +
> + if (mmc_slot(host).sdio_irq)
> + enable_irq(mmc_slot(host).sdio_irq);
> + }
> +
> + return ret;
> }
>
> static int omap_hsmmc_runtime_resume(struct device *dev)
> {
> struct omap_hsmmc_host *host;
> + struct mmc_host *mmc;
> + unsigned long flags;
> + int ret = 0;
>
> host = platform_get_drvdata(to_platform_device(dev));
> + mmc = host->mmc;
> omap_hsmmc_context_restore(host);
> dev_dbg(dev, "enabled\n");
>
> - return 0;
> + if (mmc->caps & MMC_CAP_SDIO_IRQ) {
> + if (mmc_slot(host).sdio_irq)
> + disable_irq(mmc_slot(host).sdio_irq);
> +
> + spin_lock_irqsave(&host->irq_lock, flags);
> + host->active_pinmux = true;
> +
> + if (host->sdio_irq_en) {
> + OMAP_HSMMC_WRITE(host->base, STAT, STAT_CLEAR);
> + OMAP_HSMMC_WRITE(host->base, ISE, CIRQ_EN);
> + OMAP_HSMMC_WRITE(host->base, IE, CIRQ_EN);
> + }
> + spin_unlock_irqrestore(&host->irq_lock, flags);
> + }
> + return ret;
> }
>
> static struct dev_pm_ops omap_hsmmc_dev_pm_ops = {
> diff --git a/include/linux/platform_data/mmc-omap.h b/include/linux/platform_data/mmc-omap.h
> index 2bf1b30..fd5fff5 100644
> --- a/include/linux/platform_data/mmc-omap.h
> +++ b/include/linux/platform_data/mmc-omap.h
> @@ -115,6 +115,7 @@ struct omap_mmc_platform_data {
>
> int switch_pin; /* gpio (card detect) */
> int gpio_wp; /* gpio (write protect) */
> + int gpio_cirq; /* gpio (card irq) */
>
> int (*set_bus_mode)(struct device *dev, int slot, int bus_mode);
> int (*set_power)(struct device *dev, int slot,
> @@ -145,6 +146,9 @@ struct omap_mmc_platform_data {
> int card_detect_irq;
> int (*card_detect)(struct device *dev, int slot);
>
> + /* SDIO IRQs */
> + int sdio_irq;
> +
> unsigned int ban_openended:1;
>
> } slots[OMAP_MMC_MAX_SLOTS];
>
> --
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