From ef5c48157e5fa6c574a7269743b68049ee3b9459 Mon Sep 17 00:00:00 2001 From: Jerome Brunet Date: Mon, 28 Aug 2017 16:29:03 +0200 Subject: [PATCH] mmc: meson-gx: initialize sane clk default before clock register On boot, the clock divider value is 0 which is a weird unsupported value. For example, accessing the cfg register with this value set would crash the SoC. Previous change removed 0 as possible value for CCF but forgot to properly initialize the register before registering the clock. This leads to the CCF finding an illegal value, which it complains about. Initialize the register properly in a standalone patch so the fix can be picked up if necessary. The change this fixed is: "mmc: meson-gx: remove CLK_DIVIDER_ALLOW_ZERO clock flag". Reported-by: Neil Armstrong Signed-off-by: Jerome Brunet Signed-off-by: Ulf Hansson --- drivers/mmc/host/meson-gx-mmc.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index 8a74a04..d2de5c1 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -339,6 +339,15 @@ static int meson_mmc_clk_init(struct meson_host *host) const char *clk_div_parents[1]; u32 clk_reg, cfg; + /* init SD_EMMC_CLOCK to sane defaults w/min clock rate */ + clk_reg = 0; + clk_reg |= CLK_ALWAYS_ON; + clk_reg |= CLK_DIV_MASK; + clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, host->tp.core_phase); + clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, host->tp.tx_phase); + clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, host->tp.rx_phase); + writel(clk_reg, host->regs + SD_EMMC_CLOCK); + /* get the mux parents */ for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) { struct clk *clk; @@ -393,16 +402,6 @@ static int meson_mmc_clk_init(struct meson_host *host) if (WARN_ON(PTR_ERR_OR_ZERO(host->cfg_div_clk))) return PTR_ERR(host->cfg_div_clk); - /* init SD_EMMC_CLOCK to sane defaults w/min clock rate */ - clk_reg = 0; - clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, host->tp.core_phase); - clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, host->tp.tx_phase); - clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, host->tp.rx_phase); - clk_reg |= FIELD_PREP(CLK_SRC_MASK, CLK_SRC_XTAL); - clk_reg |= FIELD_PREP(CLK_DIV_MASK, CLK_DIV_MAX); - clk_reg &= ~CLK_ALWAYS_ON; - writel(clk_reg, host->regs + SD_EMMC_CLOCK); - /* Ensure clock starts in "auto" mode, not "always on" */ cfg = readl(host->regs + SD_EMMC_CFG); cfg &= ~CFG_CLK_ALWAYS_ON; -- 2.7.4