On Mon, Jan 23, 2017 at 7:24 PM, Wei-Ning Huang <wnhuang@xxxxxxxxxx> wrote: > On Tue, Nov 8, 2016 at 2:08 PM, Yong Mao <yong.mao@xxxxxxxxxxxx> wrote: >> From: yong mao <yong.mao@xxxxxxxxxxxx> >> >> 1. Add irqlock to protect accessing the shared register >> 2. Modify the implementation of msdc_card_busy due to SDIO >> 3. Implement enable_sdio_irq >> 4. Add msdc_recheck_sdio_irq mechanism to make sure all >> interrupts can be processed immediately >> >> Signed-off-by: Yong Mao <yong.mao@xxxxxxxxxxxx> >> Signed-off-by: Chaotian Jing <chaotian.jing@xxxxxxxxxxxx> >> --- >> drivers/mmc/host/mtk-sd.c | 167 ++++++++++++++++++++++++++++++++++----------- >> 1 file changed, 129 insertions(+), 38 deletions(-) >> >> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c >> index b29683b..37edf30 100644 >> --- a/drivers/mmc/host/mtk-sd.c >> +++ b/drivers/mmc/host/mtk-sd.c >> @@ -117,6 +117,7 @@ >> #define MSDC_PS_CDSTS (0x1 << 1) /* R */ >> #define MSDC_PS_CDDEBOUNCE (0xf << 12) /* RW */ >> #define MSDC_PS_DAT (0xff << 16) /* R */ >> +#define MSDC_PS_DATA1 (0x1 << 17) /* R */ >> #define MSDC_PS_CMD (0x1 << 24) /* R */ >> #define MSDC_PS_WP (0x1 << 31) /* R */ >> >> @@ -304,6 +305,7 @@ struct msdc_host { >> int cmd_rsp; >> >> spinlock_t lock; >> + spinlock_t irqlock; /* sdio irq lock */ >> struct mmc_request *mrq; >> struct mmc_command *cmd; >> struct mmc_data *data; >> @@ -322,12 +324,14 @@ struct msdc_host { >> struct pinctrl_state *pins_uhs; >> struct delayed_work req_timeout; >> int irq; /* host interrupt */ >> + bool irq_thread_alive; >> >> struct clk *src_clk; /* msdc source clock */ >> struct clk *h_clk; /* msdc h_clk */ >> u32 mclk; /* mmc subsystem clock frequency */ >> u32 src_clk_freq; /* source clock frequency */ >> u32 sclk; /* SD/MS bus clock frequency */ >> + bool clock_on; >> unsigned char timing; >> bool vqmmc_enabled; >> u32 hs400_ds_delay; >> @@ -387,6 +391,7 @@ static void msdc_reset_hw(struct msdc_host *host) >> >> static void msdc_cmd_next(struct msdc_host *host, >> struct mmc_request *mrq, struct mmc_command *cmd); >> +static void msdc_recheck_sdio_irq(struct msdc_host *host); >> >> static const u32 cmd_ints_mask = MSDC_INTEN_CMDRDY | MSDC_INTEN_RSPCRCERR | >> MSDC_INTEN_CMDTMO | MSDC_INTEN_ACMDRDY | >> @@ -513,6 +518,7 @@ static void msdc_gate_clock(struct msdc_host *host) >> { >> clk_disable_unprepare(host->src_clk); >> clk_disable_unprepare(host->h_clk); >> + host->clock_on = false; >> } >> >> static void msdc_ungate_clock(struct msdc_host *host) >> @@ -521,6 +527,7 @@ static void msdc_ungate_clock(struct msdc_host *host) >> clk_prepare_enable(host->src_clk); >> while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB)) >> cpu_relax(); >> + host->clock_on = true; >> } >> >> static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) >> @@ -529,6 +536,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) >> u32 flags; >> u32 div; >> u32 sclk; >> + unsigned long irq_flags; >> >> if (!hz) { >> dev_dbg(host->dev, "set mclk to 0\n"); >> @@ -537,8 +545,11 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) >> return; >> } >> >> + spin_lock_irqsave(&host->irqlock, irq_flags); >> flags = readl(host->base + MSDC_INTEN); >> sdr_clr_bits(host->base + MSDC_INTEN, flags); >> + spin_unlock_irqrestore(&host->irqlock, irq_flags); >> + >> sdr_clr_bits(host->base + MSDC_CFG, MSDC_CFG_HS400_CK_MODE); >> if (timing == MMC_TIMING_UHS_DDR50 || >> timing == MMC_TIMING_MMC_DDR52 || >> @@ -588,7 +599,10 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) >> host->timing = timing; >> /* need because clk changed. */ >> msdc_set_timeout(host, host->timeout_ns, host->timeout_clks); >> + >> + spin_lock_irqsave(&host->irqlock, irq_flags); >> sdr_set_bits(host->base + MSDC_INTEN, flags); >> + spin_unlock_irqrestore(&host->irqlock, irq_flags); >> >> /* >> * mmc_select_hs400() will drop to 50Mhz and High speed mode, >> @@ -690,6 +704,7 @@ static inline u32 msdc_cmd_prepare_raw_cmd(struct msdc_host *host, >> static void msdc_start_data(struct msdc_host *host, struct mmc_request *mrq, >> struct mmc_command *cmd, struct mmc_data *data) >> { >> + unsigned long flags; >> bool read; >> >> WARN_ON(host->data); >> @@ -698,8 +713,12 @@ static void msdc_start_data(struct msdc_host *host, struct mmc_request *mrq, >> >> mod_delayed_work(system_wq, &host->req_timeout, DAT_TIMEOUT); >> msdc_dma_setup(host, &host->dma, data); >> + >> + spin_lock_irqsave(&host->irqlock, flags); >> sdr_set_bits(host->base + MSDC_INTEN, data_ints_mask); >> sdr_set_field(host->base + MSDC_DMA_CTRL, MSDC_DMA_CTRL_START, 1); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> + >> dev_dbg(host->dev, "DMA start\n"); >> dev_dbg(host->dev, "%s: cmd=%d DMA data: %d blocks; read=%d\n", >> __func__, cmd->opcode, data->blocks, read); >> @@ -756,6 +775,7 @@ static void msdc_request_done(struct msdc_host *host, struct mmc_request *mrq) >> if (mrq->data) >> msdc_unprepare_data(host, mrq); >> mmc_request_done(host->mmc, mrq); >> + msdc_recheck_sdio_irq(host); >> } >> >> /* returns true if command is fully handled; returns false otherwise */ >> @@ -779,15 +799,17 @@ static bool msdc_cmd_done(struct msdc_host *host, int events, >> | MSDC_INT_CMDTMO))) >> return done; >> >> - spin_lock_irqsave(&host->lock, flags); >> done = !host->cmd; >> + spin_lock_irqsave(&host->lock, flags); >> host->cmd = NULL; >> spin_unlock_irqrestore(&host->lock, flags); >> >> if (done) >> return true; >> >> + spin_lock_irqsave(&host->irqlock, flags); >> sdr_clr_bits(host->base + MSDC_INTEN, cmd_ints_mask); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> >> if (cmd->flags & MMC_RSP_PRESENT) { >> if (cmd->flags & MMC_RSP_136) { >> @@ -902,6 +924,7 @@ static inline bool msdc_cmd_is_ready(struct msdc_host *host, >> static void msdc_start_command(struct msdc_host *host, >> struct mmc_request *mrq, struct mmc_command *cmd) >> { >> + unsigned long flags; >> u32 rawcmd; >> >> WARN_ON(host->cmd); >> @@ -920,7 +943,10 @@ static void msdc_start_command(struct msdc_host *host, >> rawcmd = msdc_cmd_prepare_raw_cmd(host, mrq, cmd); >> mod_delayed_work(system_wq, &host->req_timeout, DAT_TIMEOUT); >> >> + spin_lock_irqsave(&host->irqlock, flags); >> sdr_set_bits(host->base + MSDC_INTEN, cmd_ints_mask); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> + >> writel(cmd->arg, host->base + SDC_ARG); >> writel(rawcmd, host->base + SDC_CMD); >> } >> @@ -1013,8 +1039,8 @@ static bool msdc_data_xfer_done(struct msdc_host *host, u32 events, >> | MSDC_INT_DMA_BDCSERR | MSDC_INT_DMA_GPDCSERR >> | MSDC_INT_DMA_PROTECT); >> >> - spin_lock_irqsave(&host->lock, flags); >> done = !host->data; >> + spin_lock_irqsave(&host->lock, flags); >> if (check_data) >> host->data = NULL; >> spin_unlock_irqrestore(&host->lock, flags); >> @@ -1029,7 +1055,11 @@ static bool msdc_data_xfer_done(struct msdc_host *host, u32 events, >> 1); >> while (readl(host->base + MSDC_DMA_CFG) & MSDC_DMA_CFG_STS) >> cpu_relax(); >> + >> + spin_lock_irqsave(&host->irqlock, flags); >> sdr_clr_bits(host->base + MSDC_INTEN, data_ints_mask); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> + >> dev_dbg(host->dev, "DMA stop\n"); >> >> if ((events & MSDC_INT_XFER_COMPL) && (!stop || !stop->error)) { >> @@ -1134,44 +1164,47 @@ static void msdc_request_timeout(struct work_struct *work) >> >> static irqreturn_t msdc_irq(int irq, void *dev_id) >> { >> + unsigned long flags; >> struct msdc_host *host = (struct msdc_host *) dev_id; >> + struct mmc_request *mrq; >> + struct mmc_command *cmd; >> + struct mmc_data *data; >> + u32 events, event_mask; >> + >> + spin_lock_irqsave(&host->irqlock, flags); >> + events = readl(host->base + MSDC_INT); >> + event_mask = readl(host->base + MSDC_INTEN); >> + /* clear interrupts */ >> + writel(events & event_mask, host->base + MSDC_INT); >> + >> + mrq = host->mrq; >> + cmd = host->cmd; >> + data = host->data; >> + spin_unlock_irqrestore(&host->irqlock, flags); >> + >> + if ((events & event_mask) & MSDC_INT_SDIOIRQ) { >> + mmc_signal_sdio_irq(host->mmc); >> + if (!mrq) >> + return IRQ_HANDLED; >> + } >> >> - while (true) { >> - unsigned long flags; >> - struct mmc_request *mrq; >> - struct mmc_command *cmd; >> - struct mmc_data *data; >> - u32 events, event_mask; >> - >> - spin_lock_irqsave(&host->lock, flags); >> - events = readl(host->base + MSDC_INT); >> - event_mask = readl(host->base + MSDC_INTEN); >> - /* clear interrupts */ >> - writel(events & event_mask, host->base + MSDC_INT); >> - >> - mrq = host->mrq; >> - cmd = host->cmd; >> - data = host->data; >> - spin_unlock_irqrestore(&host->lock, flags); >> - >> - if (!(events & event_mask)) >> - break; >> + if (!(events & (event_mask & ~MSDC_INT_SDIOIRQ))) >> + return IRQ_HANDLED; >> >> - if (!mrq) { >> - dev_err(host->dev, >> - "%s: MRQ=NULL; events=%08X; event_mask=%08X\n", >> - __func__, events, event_mask); >> - WARN_ON(1); >> - break; >> - } >> + if (!mrq) { >> + dev_err(host->dev, >> + "%s: MRQ=NULL; events=%08X; event_mask=%08X\n", >> + __func__, events, event_mask); >> + WARN_ON(1); >> + return IRQ_HANDLED; >> + } >> >> - dev_dbg(host->dev, "%s: events=%08X\n", __func__, events); >> + dev_dbg(host->dev, "%s: events=%08X\n", __func__, events); >> >> - if (cmd) >> - msdc_cmd_done(host, events, mrq, cmd); >> - else if (data) >> - msdc_data_xfer_done(host, events, mrq, data); >> - } >> + if (cmd) >> + msdc_cmd_done(host, events, mrq, cmd); >> + else if (data) >> + msdc_data_xfer_done(host, events, mrq, data); >> >> return IRQ_HANDLED; >> } >> @@ -1179,6 +1212,7 @@ static irqreturn_t msdc_irq(int irq, void *dev_id) >> static void msdc_init_hw(struct msdc_host *host) >> { >> u32 val; >> + unsigned long flags; >> >> /* Configure to MMC/SD mode, clock free running */ >> sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_MODE | MSDC_CFG_CKPDN); >> @@ -1190,9 +1224,11 @@ static void msdc_init_hw(struct msdc_host *host) >> sdr_clr_bits(host->base + MSDC_PS, MSDC_PS_CDEN); >> >> /* Disable and clear all interrupts */ >> + spin_lock_irqsave(&host->irqlock, flags); >> writel(0, host->base + MSDC_INTEN); >> val = readl(host->base + MSDC_INT); >> writel(val, host->base + MSDC_INT); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> >> writel(0, host->base + MSDC_PAD_TUNE); >> writel(0, host->base + MSDC_IOCON); >> @@ -1207,9 +1243,11 @@ static void msdc_init_hw(struct msdc_host *host) >> */ >> sdr_set_bits(host->base + SDC_CFG, SDC_CFG_SDIO); >> >> - /* disable detect SDIO device interrupt function */ >> - sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE); >> - >> + if (host->mmc->caps & MMC_CAP_SDIO_IRQ) >> + sdr_set_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE); >> + else >> + /* disable detect SDIO device interrupt function */ >> + sdr_clr_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE); >> /* Configure to default data timeout */ >> sdr_set_field(host->base + SDC_CFG, SDC_CFG_DTOC, 3); >> >> @@ -1221,11 +1259,15 @@ static void msdc_init_hw(struct msdc_host *host) >> static void msdc_deinit_hw(struct msdc_host *host) >> { >> u32 val; >> + unsigned long flags; >> + >> /* Disable and clear all interrupts */ >> + spin_lock_irqsave(&host->irqlock, flags); >> writel(0, host->base + MSDC_INTEN); >> >> val = readl(host->base + MSDC_INT); >> writel(val, host->base + MSDC_INT); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> } >> >> /* init gpd and bd list in msdc_drv_probe */ >> @@ -1493,6 +1535,52 @@ static void msdc_hw_reset(struct mmc_host *mmc) >> sdr_clr_bits(host->base + EMMC_IOCON, 1); >> } >> >> +/** >> + * msdc_recheck_sdio_irq - recheck whether the SDIO IRQ is lost >> + * @host: The host to check. >> + * >> + * Host controller may lost interrupt in some special case. >> + * Add sdio IRQ recheck mechanism to make sure all interrupts >> + * can be processed immediately >> + * >> + */ >> +static void msdc_recheck_sdio_irq(struct msdc_host *host) >> +{ >> + u32 reg_int, reg_ps; >> + >> + if (host->clock_on && >> + (host->mmc->caps & MMC_CAP_SDIO_IRQ) && >> + host->irq_thread_alive) { >> + reg_int = readl(host->base + MSDC_INT); >> + reg_ps = readl(host->base + MSDC_PS); >> + if (!((reg_int & MSDC_INT_SDIOIRQ) || >> + (reg_ps & MSDC_PS_DATA1))) { >> + mmc_signal_sdio_irq(host->mmc); >> + } >> + } >> +} >> + >> +static void msdc_enable_sdio_irq(struct mmc_host *mmc, int enable) >> +{ >> + unsigned long flags; >> + struct msdc_host *host = mmc_priv(mmc); >> + >> + host->irq_thread_alive = true; >> + if (enable) { >> + pm_runtime_get_sync(host->dev);\ > This cause problems in kernel >= 3.19. Since pm_runtime_get_sync calls > __might_sleep, and you are not suppose to sleep in a IRQ handler. Ignore above, apparently I don't know what I'm talking about ... It's actually because the sdio_irq_thread set task state to TASK_INTERRUPTABLE before calling enable_sdio_irq: set_current_state(TASK_INTERRUPTIBLE); if (host->caps & MMC_CAP_SDIO_IRQ) host->ops->enable_sdio_irq(host, 1); if (!kthread_should_stop()) schedule_timeout(period); set_current_state(TASK_RUNNING); so we are not suppose to call __might_sleep in the enable_sdio_irq callback. > > 2017-01-20T00:32:49.855603-08:00 WARNING kernel: [ 11.068860] do not > call blocking ops when !TASK_RUNNING; state=1 set at > [<ffffffc0007a350c>] sdio_irq_thread+0x11c/0x1dc > ... > 2017-01-20T00:32:49.856042-08:00 EMERG kernel: [ 12.136156] Call > trace: > 2017-01-20T00:32:49.856044-08:00 WARNING kernel: [ 12.138584] > [<ffffffc000249d84>] __might_sleep+0x64/0x90 > 2017-01-20T00:32:49.856047-08:00 WARNING kernel: [ 12.143855] > [<ffffffc000630f54>] __pm_runtime_resume+0x40/0x9c > 2017-01-20T00:32:49.856049-08:00 WARNING kernel: [ 12.149644] > [<ffffffc0007ae994>] msdc_enable_sdio_irq+0x44/0xd0 > 2017-01-20T00:32:49.856051-08:00 WARNING kernel: [ 12.155516] > [<ffffffc0007a3544>] sdio_irq_thread+0x154/0x1dc > 2017-01-20T00:32:49.856053-08:00 WARNING kernel: [ 12.161131] > [<ffffffc00023f30c>] kthread+0x10c/0x114 > 2017-01-20T00:32:49.856055-08:00 WARNING kernel: [ 12.166056] > [<ffffffc000203dd0>] ret_from_fork+0x10/0x40 > 2017-01-20T00:32:49.856057-08:00 WARNING kernel: [ 12.171368] sched: > RT throttling activated for rt_rq ffffffc0fff5a5c0 (cpu 1) > 2017-01-20T00:32:49.856059-08:00 WARNING kernel: [ 12.171368] > potential CPU hogs: > 2017-01-20T00:32:49.856061-08:00 WARNING kernel: [ 12.171368] > ksdioirqd/mmc2 (1772) > > dw_mmc also enables autosuspend but it didn't call any pm_runtime_get* > function in it's enable_sdio_irq function, I don't really know how it > worked around this. > Ulf, any suggestions on how we can do this? > > Wei-Ning > >> + msdc_recheck_sdio_irq(host); >> + >> + spin_lock_irqsave(&host->irqlock, flags); >> + sdr_set_bits(host->base + SDC_CFG, SDC_CFG_SDIOIDE); >> + sdr_set_bits(host->base + MSDC_INTEN, MSDC_INTEN_SDIOIRQ); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> + } else { >> + spin_lock_irqsave(&host->irqlock, flags); >> + sdr_clr_bits(host->base + MSDC_INTEN, MSDC_INTEN_SDIOIRQ); >> + spin_unlock_irqrestore(&host->irqlock, flags); >> + } >> +} >> + >> static struct mmc_host_ops mt_msdc_ops = { >> .post_req = msdc_post_req, >> .pre_req = msdc_pre_req, >> @@ -1504,6 +1592,7 @@ static void msdc_hw_reset(struct mmc_host *mmc) >> .execute_tuning = msdc_execute_tuning, >> .prepare_hs400_tuning = msdc_prepare_hs400_tuning, >> .hw_reset = msdc_hw_reset, >> + .enable_sdio_irq = msdc_enable_sdio_irq, >> }; >> >> static int msdc_drv_probe(struct platform_device *pdev) >> @@ -1600,6 +1689,7 @@ static int msdc_drv_probe(struct platform_device *pdev) >> mmc_dev(mmc)->dma_mask = &host->dma_mask; >> >> host->timeout_clks = 3 * 1048576; >> + host->irq_thread_alive = false; >> host->dma.gpd = dma_alloc_coherent(&pdev->dev, >> 2 * sizeof(struct mt_gpdma_desc), >> &host->dma.gpd_addr, GFP_KERNEL); >> @@ -1613,6 +1703,7 @@ static int msdc_drv_probe(struct platform_device *pdev) >> msdc_init_gpd_bd(host, &host->dma); >> INIT_DELAYED_WORK(&host->req_timeout, msdc_request_timeout); >> spin_lock_init(&host->lock); >> + spin_lock_init(&host->irqlock); >> >> platform_set_drvdata(pdev, mmc); >> msdc_ungate_clock(host); >> -- >> 1.7.9.5 >> > > > > -- > Wei-Ning Huang, 黃偉寧 | Software Engineer, Google Inc., Taiwan | > wnhuang@xxxxxxxxxx | Cell: +886 910-380678 -- Wei-Ning Huang, 黃偉寧 | Software Engineer, Google Inc., Taiwan | wnhuang@xxxxxxxxxx | Cell: +886 910-380678 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html