If dma-coherent property isn't set then descriptors are non-cacheable and the iocc shareability bits should be disabled. Without this UFS can end up in an incompatible configuration and suffer from random cache related stability issues.
Suggested-by: Bart Van Assche bvanassche@acm.org Fixes: cc52e15397cc ("scsi: ufs: ufs-exynos: Support ExynosAuto v9 UFS") Signed-off-by: Peter Griffin peter.griffin@linaro.org Cc: Chanho Park chanho61.park@samsung.com Cc: stable@vger.kernel.org --- drivers/ufs/host/ufs-exynos.c | 17 +++++++++++++---- drivers/ufs/host/ufs-exynos.h | 3 ++- 2 files changed, 15 insertions(+), 5 deletions(-)
diff --git a/drivers/ufs/host/ufs-exynos.c b/drivers/ufs/host/ufs-exynos.c index f393d42a659f821225e67e3e5d323478456ca3af..61b03e493cc1ddba17179a9f22e5b59ece02458b 100644 --- a/drivers/ufs/host/ufs-exynos.c +++ b/drivers/ufs/host/ufs-exynos.c @@ -214,8 +214,8 @@ static int exynos_ufs_shareability(struct exynos_ufs *ufs) /* IO Coherency setting */ if (ufs->sysreg) { return regmap_update_bits(ufs->sysreg, - ufs->shareability_reg_offset, - ufs->iocc_mask, ufs->iocc_mask); + ufs->iocc_offset, + ufs->iocc_mask, ufs->iocc_val); }
return 0; @@ -1173,13 +1173,22 @@ static int exynos_ufs_parse_dt(struct device *dev, struct exynos_ufs *ufs) ufs->sysreg = NULL; else { if (of_property_read_u32_index(np, "samsung,sysreg", 1, - &ufs->shareability_reg_offset)) { + &ufs->iocc_offset)) { dev_warn(dev, "can't get an offset from sysreg. Set to default value\n"); - ufs->shareability_reg_offset = UFS_SHAREABILITY_OFFSET; + ufs->iocc_offset = UFS_SHAREABILITY_OFFSET; } }
ufs->iocc_mask = ufs->drv_data->iocc_mask; + /* + * no 'dma-coherent' property means the descriptors are + * non-cacheable so iocc shareability should be disabled. + */ + if (of_dma_is_coherent(dev->of_node)) + ufs->iocc_val = ufs->iocc_mask; + else + ufs->iocc_val = 0; + ufs->pclk_avail_min = PCLK_AVAIL_MIN; ufs->pclk_avail_max = PCLK_AVAIL_MAX;
diff --git a/drivers/ufs/host/ufs-exynos.h b/drivers/ufs/host/ufs-exynos.h index 17696b3768debd641188b5089585b6d303de7451..a345809af79dc528ad518d3572fe8be034341ee0 100644 --- a/drivers/ufs/host/ufs-exynos.h +++ b/drivers/ufs/host/ufs-exynos.h @@ -231,8 +231,9 @@ struct exynos_ufs { ktime_t entry_hibern8_t; const struct exynos_ufs_drv_data *drv_data; struct regmap *sysreg; - u32 shareability_reg_offset; + u32 iocc_offset; u32 iocc_mask; + u32 iocc_val;
u32 opts; #define EXYNOS_UFS_OPT_HAS_APB_CLK_CTRL BIT(0)