[PATCH 5.0 063/238] mmc: renesas_sdhi: Fix card initialization failure in high speed mode

From: Greg Kroah-Hartman
Date: Fri Mar 22 2019 - 08:16:23 EST


5.0-stable review patch. If anyone has any objections, please let me know.

------------------

From: Takeshi Saito <takeshi.saito.xv@xxxxxxxxxxx>

commit d30ae056adb81e1d2b8b953efa74735a020b8e3b upstream.

This fixes card initialization failure in high speed mode.

If U-Boot uses SDR or HS200/400 mode before starting Linux and Linux
DT does not enable SDR/HS200/HS400 mode, card initialization fails in
high speed mode.

It is necessary to initialize SCC registers during card initialization
phase. HW reset function is registered only for a port with either of
SDR/HS200/HS400 properties in device tree. If SDR/HS200/HS400 properties
are not present in device tree, SCC registers will not be reset. In SoC
that support SCC registers, HW reset function should be registered
regardless of the configuration of device tree.

Reproduction procedure:
- Use U-Boot that support MMC HS200/400 mode.
- Delete HS200/HS400 properties in device tree.
(Delete mmc-hs200-1_8v and mmc-hs400-1_8v)
- MMC port works high speed mode and all commands fail.

Signed-off-by: Takeshi Saito <takeshi.saito.xv@xxxxxxxxxxx>
Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
Cc: Niklas SÃderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
Cc: Simon Horman <horms+renesas@xxxxxxxxxxxx>
Reviewed-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/host/renesas_sdhi_core.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

--- a/drivers/mmc/host/renesas_sdhi_core.c
+++ b/drivers/mmc/host/renesas_sdhi_core.c
@@ -723,6 +723,13 @@ int renesas_sdhi_probe(struct platform_d
host->ops.start_signal_voltage_switch =
renesas_sdhi_start_signal_voltage_switch;
host->sdcard_irq_setbit_mask = TMIO_STAT_ALWAYS_SET_27;
+
+ /* SDR and HS200/400 registers requires HW reset */
+ if (of_data && of_data->scc_offset) {
+ priv->scc_ctl = host->ctl + of_data->scc_offset;
+ host->mmc->caps |= MMC_CAP_HW_RESET;
+ host->hw_reset = renesas_sdhi_hw_reset;
+ }
}

/* Orginally registers were 16 bit apart, could be 32 or 64 nowadays */
@@ -775,8 +782,6 @@ int renesas_sdhi_probe(struct platform_d
const struct renesas_sdhi_scc *taps = of_data->taps;
bool hit = false;

- host->mmc->caps |= MMC_CAP_HW_RESET;
-
for (i = 0; i < of_data->taps_num; i++) {
if (taps[i].clk_rate == 0 ||
taps[i].clk_rate == host->mmc->f_max) {
@@ -789,12 +794,10 @@ int renesas_sdhi_probe(struct platform_d
if (!hit)
dev_warn(&host->pdev->dev, "Unknown clock rate for SDR104\n");

- priv->scc_ctl = host->ctl + of_data->scc_offset;
host->init_tuning = renesas_sdhi_init_tuning;
host->prepare_tuning = renesas_sdhi_prepare_tuning;
host->select_tuning = renesas_sdhi_select_tuning;
host->check_scc_error = renesas_sdhi_check_scc_error;
- host->hw_reset = renesas_sdhi_hw_reset;
host->prepare_hs400_tuning =
renesas_sdhi_prepare_hs400_tuning;
host->hs400_downgrade = renesas_sdhi_disable_scc;