From 3c6b94d7091f0793445f2faf777e584af643e9da Mon Sep 17 00:00:00 2001 From: Chaotian Jing Date: Mon, 16 Oct 2017 09:46:36 +0800 Subject: [PATCH 157/224] mmc: mediatek: add support of source_cg clock source clock need an independent cg to control, when doing clk mode switch, need gate source clock to avoid hw issue(multi-bit sync hw hang) Signed-off-by: Chaotian Jing Tested-by: Sean Wang Signed-off-by: Ulf Hansson --- drivers/mmc/host/mtk-sd.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -374,6 +374,7 @@ struct msdc_host { struct clk *src_clk; /* msdc source clock */ struct clk *h_clk; /* msdc h_clk */ + struct clk *src_clk_cg; /* msdc source clock control gate */ u32 mclk; /* mmc subsystem clock frequency */ u32 src_clk_freq; /* source clock frequency */ u32 sclk; /* SD/MS bus clock frequency */ @@ -618,6 +619,7 @@ static void msdc_set_timeout(struct msdc static void msdc_gate_clock(struct msdc_host *host) { + clk_disable_unprepare(host->src_clk_cg); clk_disable_unprepare(host->src_clk); clk_disable_unprepare(host->h_clk); } @@ -626,6 +628,7 @@ static void msdc_ungate_clock(struct msd { clk_prepare_enable(host->h_clk); clk_prepare_enable(host->src_clk); + clk_prepare_enable(host->src_clk_cg); while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB)) cpu_relax(); } @@ -694,6 +697,15 @@ static void msdc_set_mclk(struct msdc_ho sclk = (host->src_clk_freq >> 2) / div; } } + sdr_clr_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN); + /* + * As src_clk/HCLK use the same bit to gate/ungate, + * So if want to only gate src_clk, need gate its parent(mux). + */ + if (host->src_clk_cg) + clk_disable_unprepare(host->src_clk_cg); + else + clk_disable_unprepare(clk_get_parent(host->src_clk)); if (host->dev_comp->clk_div_bits == 8) sdr_set_field(host->base + MSDC_CFG, MSDC_CFG_CKMOD | MSDC_CFG_CKDIV, @@ -702,10 +714,14 @@ static void msdc_set_mclk(struct msdc_ho sdr_set_field(host->base + MSDC_CFG, MSDC_CFG_CKMOD_EXTRA | MSDC_CFG_CKDIV_EXTRA, (mode << 12) | div); + if (host->src_clk_cg) + clk_prepare_enable(host->src_clk_cg); + else + clk_prepare_enable(clk_get_parent(host->src_clk)); - sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN); while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB)) cpu_relax(); + sdr_set_bits(host->base + MSDC_CFG, MSDC_CFG_CKPDN); host->sclk = sclk; host->mclk = hz; host->timing = timing; @@ -1825,6 +1841,11 @@ static int msdc_drv_probe(struct platfor goto host_free; } + /*source clock control gate is optional clock*/ + host->src_clk_cg = devm_clk_get(&pdev->dev, "source_cg"); + if (IS_ERR(host->src_clk_cg)) + host->src_clk_cg = NULL; + host->irq = platform_get_irq(pdev, 0); if (host->irq < 0) { ret = -EINVAL;