From: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com
[ Upstream commit ffaea6ebfe9ce06ebb3a54811a47688f2b0893cd ]
Replace all instances of open-coded while loops for polling registers with calls to readl_poll_timeout() and, while at it, also fix some possible infinite loop instances.
Signed-off-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Link: https://lore.kernel.org/r/20211216125748.179602-1-angelogioacchino.delregno@... Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/host/mtk-sd.c | 64 ++++++++++++++++++++++++--------------- 1 file changed, 39 insertions(+), 25 deletions(-)
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 632775217d35c..d5a9c269d4926 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -636,12 +636,11 @@ static void msdc_reset_hw(struct msdc_host *host) u32 val;
sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_RST); - while (readl(host->base + MSDC_CFG) & MSDC_CFG_RST) - cpu_relax(); + readl_poll_timeout(host->base + MSDC_CFG, val, !(val & MSDC_CFG_RST), 0, 0);
sdr_set_bits(host->base + MSDC_FIFOCS, MSDC_FIFOCS_CLR); - while (readl(host->base + MSDC_FIFOCS) & MSDC_FIFOCS_CLR) - cpu_relax(); + readl_poll_timeout(host->base + MSDC_FIFOCS, val, + !(val & MSDC_FIFOCS_CLR), 0, 0);
val = readl(host->base + MSDC_INT); writel(val, host->base + MSDC_INT); @@ -814,8 +813,9 @@ static void msdc_gate_clock(struct msdc_host *host) clk_disable_unprepare(host->h_clk); }
-static void msdc_ungate_clock(struct msdc_host *host) +static int msdc_ungate_clock(struct msdc_host *host) { + u32 val; int ret;
clk_prepare_enable(host->h_clk); @@ -825,11 +825,11 @@ static void msdc_ungate_clock(struct msdc_host *host) ret = clk_bulk_prepare_enable(MSDC_NR_CLOCKS, host->bulk_clks); if (ret) { dev_err(host->dev, "Cannot enable pclk/axi/ahb clock gates\n"); - return; + return ret; }
- while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB)) - cpu_relax(); + return readl_poll_timeout(host->base + MSDC_CFG, val, + (val & MSDC_CFG_CKSTB), 1, 20000); }
static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) @@ -840,6 +840,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) u32 div; u32 sclk; u32 tune_reg = host->dev_comp->pad_tune_reg; + u32 val;
if (!hz) { dev_dbg(host->dev, "set mclk to 0\n"); @@ -920,8 +921,7 @@ static void msdc_set_mclk(struct msdc_host *host, unsigned char timing, u32 hz) else clk_prepare_enable(clk_get_parent(host->src_clk));
- while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB)) - cpu_relax(); + readl_poll_timeout(host->base + MSDC_CFG, val, (val & MSDC_CFG_CKSTB), 0, 0); sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN); mmc->actual_clock = sclk; host->mclk = hz; @@ -1231,13 +1231,13 @@ static bool msdc_cmd_done(struct msdc_host *host, int events, static inline bool msdc_cmd_is_ready(struct msdc_host *host, struct mmc_request *mrq, struct mmc_command *cmd) { - /* The max busy time we can endure is 20ms */ - unsigned long tmo = jiffies + msecs_to_jiffies(20); + u32 val; + int ret;
- while ((readl(host->base + SDC_STS) & SDC_STS_CMDBUSY) && - time_before(jiffies, tmo)) - cpu_relax(); - if (readl(host->base + SDC_STS) & SDC_STS_CMDBUSY) { + /* The max busy time we can endure is 20ms */ + ret = readl_poll_timeout_atomic(host->base + SDC_STS, val, + !(val & SDC_STS_CMDBUSY), 1, 20000); + if (ret) { dev_err(host->dev, "CMD bus busy detected\n"); host->error |= REQ_CMD_BUSY; msdc_cmd_done(host, MSDC_INT_CMDTMO, mrq, cmd); @@ -1245,12 +1245,10 @@ static inline bool msdc_cmd_is_ready(struct msdc_host *host, }
if (mmc_resp_type(cmd) == MMC_RSP_R1B || cmd->data) { - tmo = jiffies + msecs_to_jiffies(20); /* R1B or with data, should check SDCBUSY */ - while ((readl(host->base + SDC_STS) & SDC_STS_SDCBUSY) && - time_before(jiffies, tmo)) - cpu_relax(); - if (readl(host->base + SDC_STS) & SDC_STS_SDCBUSY) { + ret = readl_poll_timeout_atomic(host->base + SDC_STS, val, + !(val & SDC_STS_SDCBUSY), 1, 20000); + if (ret) { dev_err(host->dev, "Controller busy detected\n"); host->error |= REQ_CMD_BUSY; msdc_cmd_done(host, MSDC_INT_CMDTMO, mrq, cmd); @@ -1376,6 +1374,8 @@ static bool msdc_data_xfer_done(struct msdc_host *host, u32 events, (MSDC_INT_XFER_COMPL | MSDC_INT_DATCRCERR | MSDC_INT_DATTMO | MSDC_INT_DMA_BDCSERR | MSDC_INT_DMA_GPDCSERR | MSDC_INT_DMA_PROTECT); + u32 val; + int ret;
spin_lock_irqsave(&host->lock, flags); done = !host->data; @@ -1392,8 +1392,14 @@ static bool msdc_data_xfer_done(struct msdc_host *host, u32 events, readl(host->base + MSDC_DMA_CFG)); sdr_set_field(host->base + MSDC_DMA_CTRL, MSDC_DMA_CTRL_STOP, 1); - while (readl(host->base + MSDC_DMA_CFG) & MSDC_DMA_CFG_STS) - cpu_relax(); + + ret = readl_poll_timeout_atomic(host->base + MSDC_DMA_CFG, val, + !(val & MSDC_DMA_CFG_STS), 1, 20000); + if (ret) { + dev_dbg(host->dev, "DMA stop timed out\n"); + return false; + } + sdr_clr_bits(host->base + MSDC_INTEN, data_ints_mask); dev_dbg(host->dev, "DMA stop\n");
@@ -2674,7 +2680,11 @@ static int msdc_drv_probe(struct platform_device *pdev) spin_lock_init(&host->lock);
platform_set_drvdata(pdev, mmc); - msdc_ungate_clock(host); + ret = msdc_ungate_clock(host); + if (ret) { + dev_err(&pdev->dev, "Cannot ungate clocks!\n"); + goto release_mem; + } msdc_init_hw(host);
if (mmc->caps2 & MMC_CAP2_CQE) { @@ -2833,8 +2843,12 @@ static int __maybe_unused msdc_runtime_resume(struct device *dev) { struct mmc_host *mmc = dev_get_drvdata(dev); struct msdc_host *host = mmc_priv(mmc); + int ret; + + ret = msdc_ungate_clock(host); + if (ret) + return ret;
- msdc_ungate_clock(host); msdc_restore_reg(host); return 0; }