Re: [PATCH 2/4] sdio: mediatek: Support sdio feature
From: Wei-Ning Huang <hidden>
Date: 2017-01-23 11:24:17
Also in:
linux-arm-kernel, linux-mediatek, linux-mmc, lkml
On Tue, Nov 8, 2016 at 2:08 PM, Yong Mao [off-list ref] wrote:
quoted hunk ↗ jump to hunk
From: yong mao <redacted> 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 <redacted> Signed-off-by: Chaotian Jing <chaotian.jing@mediatek.com> --- 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. 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
quoted hunk ↗ jump to hunk
+ 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@google.com | Cell: +886 910-380678