aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mmc
diff options
context:
space:
mode:
authorZiyang Huang <hzyitc@outlook.com>2023-10-11 00:44:00 +0800
committerUlf Hansson <ulf.hansson@linaro.org>2023-12-07 14:08:19 +0100
commit8c124d998ea0c9022e247b11ac51f86ec8afa0e1 (patch)
treec4889ba89b76ada03af774de26f7d3e52c4e48d8 /drivers/mmc
parent33cc938e65a98f1d29d0a18403dbbee050dcad9a (diff)
downloadlinux-8c124d998ea0c9022e247b11ac51f86ec8afa0e1.tar.gz
mmc: meson-mx-sdhc: Fix initialization frozen issue
Commit 4bc31edebde5 ("mmc: core: Set HS clock speed before sending HS CMD13") set HS clock (52MHz) before switching to HS mode. For this freq, FCLK_DIV5 will be selected and div value is 10 (reg value is 9). Then we set rx_clk_phase to 11 or 15 which is out of range and make hardware frozen. After we send command request, no irq will be interrupted and the mmc driver will keep to wait for request finished, even durning rebooting. So let's set it to Phase 90 which should work in most cases. Then let meson_mx_sdhc_execute_tuning() to find the accurate value for data transfer. If this doesn't work, maybe need to define a factor in dts. Fixes: e4bf1b0970ef ("mmc: host: meson-mx-sdhc: new driver for the Amlogic Meson SDHC host") Signed-off-by: Ziyang Huang <hzyitc@outlook.com> Tested-by: Anand Moon <linux.amoon@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/TYZPR01MB5556A3E71554A2EC08597EA4C9CDA@TYZPR01MB5556.apcprd01.prod.exchangelabs.com Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc')
-rw-r--r--drivers/mmc/host/meson-mx-sdhc-mmc.c26
1 files changed, 5 insertions, 21 deletions
diff --git a/drivers/mmc/host/meson-mx-sdhc-mmc.c b/drivers/mmc/host/meson-mx-sdhc-mmc.c
index 528ec8166e7c36..1ed9731e77ef59 100644
--- a/drivers/mmc/host/meson-mx-sdhc-mmc.c
+++ b/drivers/mmc/host/meson-mx-sdhc-mmc.c
@@ -269,7 +269,7 @@ static int meson_mx_sdhc_enable_clks(struct mmc_host *mmc)
static int meson_mx_sdhc_set_clk(struct mmc_host *mmc, struct mmc_ios *ios)
{
struct meson_mx_sdhc_host *host = mmc_priv(mmc);
- u32 rx_clk_phase;
+ u32 val, rx_clk_phase;
int ret;
meson_mx_sdhc_disable_clks(mmc);
@@ -290,27 +290,11 @@ static int meson_mx_sdhc_set_clk(struct mmc_host *mmc, struct mmc_ios *ios)
mmc->actual_clock = clk_get_rate(host->sd_clk);
/*
- * according to Amlogic the following latching points are
- * selected with empirical values, there is no (known) formula
- * to calculate these.
+ * Phase 90 should work in most cases. For data transmission,
+ * meson_mx_sdhc_execute_tuning() will find a accurate value
*/
- if (mmc->actual_clock > 100000000) {
- rx_clk_phase = 1;
- } else if (mmc->actual_clock > 45000000) {
- if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
- rx_clk_phase = 15;
- else
- rx_clk_phase = 11;
- } else if (mmc->actual_clock >= 25000000) {
- rx_clk_phase = 15;
- } else if (mmc->actual_clock > 5000000) {
- rx_clk_phase = 23;
- } else if (mmc->actual_clock > 1000000) {
- rx_clk_phase = 55;
- } else {
- rx_clk_phase = 1061;
- }
-
+ regmap_read(host->regmap, MESON_SDHC_CLKC, &val);
+ rx_clk_phase = FIELD_GET(MESON_SDHC_CLKC_CLK_DIV, val) / 4;
regmap_update_bits(host->regmap, MESON_SDHC_CLK2,
MESON_SDHC_CLK2_RX_CLK_PHASE,
FIELD_PREP(MESON_SDHC_CLK2_RX_CLK_PHASE,