From: Jerome Brunet jbrunet@baylibre.com
[ Upstream commit 18f92bc02f1739b5c4d5b70009fbb7eada45bca3 ]
On errors, if we don't stop the descriptor chain, it may continue to run and raise IRQ after we have called mmc_request_done(). This is bad because we won't be able to get cmd anymore and properly deal with the IRQ.
This patch makes sure the descriptor chain is stopped before calling mmc_request_done()
Fixes: 79ed05e329c3 ("mmc: meson-gx: add support for descriptor chain mode") Signed-off-by: Jerome Brunet jbrunet@baylibre.com Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/host/meson-gx-mmc.c | 73 ++++++++++++++++++++++++++++----- 1 file changed, 63 insertions(+), 10 deletions(-)
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index ddd98cdd33bcd..72f34a58928ca 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -21,6 +21,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> +#include <linux/delay.h> #include <linux/device.h> #include <linux/of_device.h> #include <linux/platform_device.h> @@ -90,9 +91,11 @@ #define CFG_CLK_ALWAYS_ON BIT(18) #define CFG_CHK_DS BIT(20) #define CFG_AUTO_CLK BIT(23) +#define CFG_ERR_ABORT BIT(27)
#define SD_EMMC_STATUS 0x48 #define STATUS_BUSY BIT(31) +#define STATUS_DESC_BUSY BIT(30) #define STATUS_DATI GENMASK(23, 16)
#define SD_EMMC_IRQ_EN 0x4c @@ -930,6 +933,7 @@ static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
cmd_cfg |= FIELD_PREP(CMD_CFG_CMD_INDEX_MASK, cmd->opcode); cmd_cfg |= CMD_CFG_OWNER; /* owned by CPU */ + cmd_cfg |= CMD_CFG_ERROR; /* stop in case of error */
meson_mmc_set_response_bits(cmd, &cmd_cfg);
@@ -1024,6 +1028,17 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id) u32 irq_en, status, raw_status; irqreturn_t ret = IRQ_NONE;
+ irq_en = readl(host->regs + SD_EMMC_IRQ_EN); + raw_status = readl(host->regs + SD_EMMC_STATUS); + status = raw_status & irq_en; + + if (!status) { + dev_dbg(host->dev, + "Unexpected IRQ! irq_en 0x%08x - status 0x%08x\n", + irq_en, raw_status); + return IRQ_NONE; + } + if (WARN_ON(!host) || WARN_ON(!host->cmd)) return IRQ_NONE;
@@ -1031,22 +1046,18 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
cmd = host->cmd; data = cmd->data; - irq_en = readl(host->regs + SD_EMMC_IRQ_EN); - raw_status = readl(host->regs + SD_EMMC_STATUS); - status = raw_status & irq_en; - cmd->error = 0; if (status & IRQ_CRC_ERR) { dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status); cmd->error = -EILSEQ; - ret = IRQ_HANDLED; + ret = IRQ_WAKE_THREAD; goto out; }
if (status & IRQ_TIMEOUTS) { dev_dbg(host->dev, "Timeout - status 0x%08x\n", status); cmd->error = -ETIMEDOUT; - ret = IRQ_HANDLED; + ret = IRQ_WAKE_THREAD; goto out; }
@@ -1071,17 +1082,49 @@ static irqreturn_t meson_mmc_irq(int irq, void *dev_id) /* ack all enabled interrupts */ writel(irq_en, host->regs + SD_EMMC_STATUS);
+ if (cmd->error) { + /* Stop desc in case of errors */ + u32 start = readl(host->regs + SD_EMMC_START); + + start &= ~START_DESC_BUSY; + writel(start, host->regs + SD_EMMC_START); + } + if (ret == IRQ_HANDLED) meson_mmc_request_done(host->mmc, cmd->mrq); - else if (ret == IRQ_NONE) - dev_warn(host->dev, - "Unexpected IRQ! status=0x%08x, irq_en=0x%08x\n", - raw_status, irq_en);
spin_unlock(&host->lock); return ret; }
+static int meson_mmc_wait_desc_stop(struct meson_host *host) +{ + int loop; + u32 status; + + /* + * It may sometimes take a while for it to actually halt. Here, we + * are giving it 5ms to comply + * + * If we don't confirm the descriptor is stopped, it might raise new + * IRQs after we have called mmc_request_done() which is bad. + */ + for (loop = 50; loop; loop--) { + status = readl(host->regs + SD_EMMC_STATUS); + if (status & (STATUS_BUSY | STATUS_DESC_BUSY)) + udelay(100); + else + break; + } + + if (status & (STATUS_BUSY | STATUS_DESC_BUSY)) { + dev_err(host->dev, "Timed out waiting for host to stop\n"); + return -ETIMEDOUT; + } + + return 0; +} + static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id) { struct meson_host *host = dev_id; @@ -1092,6 +1135,13 @@ static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id) if (WARN_ON(!cmd)) return IRQ_NONE;
+ if (cmd->error) { + meson_mmc_wait_desc_stop(host); + meson_mmc_request_done(host->mmc, cmd->mrq); + + return IRQ_HANDLED; + } + data = cmd->data; if (meson_mmc_bounce_buf_read(data)) { xfer_bytes = data->blksz * data->blocks; @@ -1132,6 +1182,9 @@ static void meson_mmc_cfg_init(struct meson_host *host) cfg |= FIELD_PREP(CFG_RC_CC_MASK, ilog2(SD_EMMC_CFG_CMD_GAP)); cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, ilog2(SD_EMMC_CFG_BLK_SIZE));
+ /* abort chain on R/W errors */ + cfg |= CFG_ERR_ABORT; + writel(cfg, host->regs + SD_EMMC_CFG); }