2022-03-02 16:53:51

by Ricky Wu

[permalink] [raw]
Subject: [PATCH v2] mmc: rtsx: add 74 Clocks in power on flow

SD spec definition:
"Host provides at least 74 Clocks before issuing first command"
After 1ms for the voltage stable then start issuing the Clock signals

if POWER STATE is
MMC_POWER_OFF to MMC_POWER_UP to issue Clock signal to card
MMC_POWER_UP to MMC_POWER_ON to stop issuing signal to card

Signed-off-by: Ricky Wu <[email protected]>
---
v2:
modify commit message
move mdelay(5) to host->power_delay_ms
replace host->power_state with host->prev_power_state
---
drivers/mmc/host/rtsx_pci_sdmmc.c | 29 +++++++++++++++++++----------
1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c
index 2a3f14afe9f8..d26803d3f4ca 100644
--- a/drivers/mmc/host/rtsx_pci_sdmmc.c
+++ b/drivers/mmc/host/rtsx_pci_sdmmc.c
@@ -38,10 +38,7 @@ struct realtek_pci_sdmmc {
bool double_clk;
bool eject;
bool initial_mode;
- int power_state;
-#define SDMMC_POWER_ON 1
-#define SDMMC_POWER_OFF 0
-
+ int prev_power_state;
int sg_count;
s32 cookie;
int cookie_sg_count;
@@ -909,7 +906,7 @@ static int sd_set_bus_width(struct realtek_pci_sdmmc *host,
return err;
}

-static int sd_power_on(struct realtek_pci_sdmmc *host)
+static int sd_power_on(struct realtek_pci_sdmmc *host, unsigned char power_mode)
{
struct rtsx_pcr *pcr = host->pcr;
struct mmc_host *mmc = host->mmc;
@@ -917,9 +914,14 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
u32 val;
u8 test_mode;

- if (host->power_state == SDMMC_POWER_ON)
+ if (host->prev_power_state == MMC_POWER_ON)
return 0;

+ if (host->prev_power_state == MMC_POWER_UP) {
+ rtsx_pci_write_register(pcr, SD_BUS_STAT, SD_CLK_TOGGLE_EN, 0);
+ goto finish;
+ }
+
msleep(100);

rtsx_pci_init_cmd(pcr);
@@ -940,10 +942,15 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
if (err < 0)
return err;

+ mdelay(1);
+
err = rtsx_pci_write_register(pcr, CARD_OE, SD_OUTPUT_EN, SD_OUTPUT_EN);
if (err < 0)
return err;

+ /* send at least 74 clocks */
+ rtsx_pci_write_register(pcr, SD_BUS_STAT, SD_CLK_TOGGLE_EN, SD_CLK_TOGGLE_EN);
+
if (PCI_PID(pcr) == PID_5261) {
/*
* If test mode is set switch to SD Express mandatorily,
@@ -968,7 +975,8 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
}
}

- host->power_state = SDMMC_POWER_ON;
+finish:
+ host->prev_power_state = power_mode;
return 0;
}

@@ -977,7 +985,7 @@ static int sd_power_off(struct realtek_pci_sdmmc *host)
struct rtsx_pcr *pcr = host->pcr;
int err;

- host->power_state = SDMMC_POWER_OFF;
+ host->prev_power_state = MMC_POWER_OFF;

rtsx_pci_init_cmd(pcr);

@@ -1003,7 +1011,7 @@ static int sd_set_power_mode(struct realtek_pci_sdmmc *host,
if (power_mode == MMC_POWER_OFF)
err = sd_power_off(host);
else
- err = sd_power_on(host);
+ err = sd_power_on(host, power_mode);

return err;
}
@@ -1506,10 +1514,11 @@ static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)

host = mmc_priv(mmc);
host->pcr = pcr;
+ mmc->ios.power_delay_ms = 5;
host->mmc = mmc;
host->pdev = pdev;
host->cookie = -1;
- host->power_state = SDMMC_POWER_OFF;
+ host->prev_power_state = MMC_POWER_OFF;
INIT_WORK(&host->work, sd_request);
platform_set_drvdata(pdev, host);
pcr->slots[RTSX_SD_CARD].p_dev = pdev;
--
2.25.1


2022-03-03 00:27:28

by Ulf Hansson

[permalink] [raw]
Subject: Re: [PATCH v2] mmc: rtsx: add 74 Clocks in power on flow

On Wed, 2 Mar 2022 at 10:43, Ricky WU <[email protected]> wrote:
>
> SD spec definition:
> "Host provides at least 74 Clocks before issuing first command"
> After 1ms for the voltage stable then start issuing the Clock signals
>
> if POWER STATE is
> MMC_POWER_OFF to MMC_POWER_UP to issue Clock signal to card
> MMC_POWER_UP to MMC_POWER_ON to stop issuing signal to card
>
> Signed-off-by: Ricky Wu <[email protected]>

Applied for next, thanks!

Greg, I verified that this shouldn't conflict with the changes you
have picked up already for the rtsx mmc driver.

Kind regards
Uffe

> ---
> v2:
> modify commit message
> move mdelay(5) to host->power_delay_ms
> replace host->power_state with host->prev_power_state
> ---
> drivers/mmc/host/rtsx_pci_sdmmc.c | 29 +++++++++++++++++++----------
> 1 file changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c
> index 2a3f14afe9f8..d26803d3f4ca 100644
> --- a/drivers/mmc/host/rtsx_pci_sdmmc.c
> +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c
> @@ -38,10 +38,7 @@ struct realtek_pci_sdmmc {
> bool double_clk;
> bool eject;
> bool initial_mode;
> - int power_state;
> -#define SDMMC_POWER_ON 1
> -#define SDMMC_POWER_OFF 0
> -
> + int prev_power_state;
> int sg_count;
> s32 cookie;
> int cookie_sg_count;
> @@ -909,7 +906,7 @@ static int sd_set_bus_width(struct realtek_pci_sdmmc *host,
> return err;
> }
>
> -static int sd_power_on(struct realtek_pci_sdmmc *host)
> +static int sd_power_on(struct realtek_pci_sdmmc *host, unsigned char power_mode)
> {
> struct rtsx_pcr *pcr = host->pcr;
> struct mmc_host *mmc = host->mmc;
> @@ -917,9 +914,14 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
> u32 val;
> u8 test_mode;
>
> - if (host->power_state == SDMMC_POWER_ON)
> + if (host->prev_power_state == MMC_POWER_ON)
> return 0;
>
> + if (host->prev_power_state == MMC_POWER_UP) {
> + rtsx_pci_write_register(pcr, SD_BUS_STAT, SD_CLK_TOGGLE_EN, 0);
> + goto finish;
> + }
> +
> msleep(100);
>
> rtsx_pci_init_cmd(pcr);
> @@ -940,10 +942,15 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
> if (err < 0)
> return err;
>
> + mdelay(1);
> +
> err = rtsx_pci_write_register(pcr, CARD_OE, SD_OUTPUT_EN, SD_OUTPUT_EN);
> if (err < 0)
> return err;
>
> + /* send at least 74 clocks */
> + rtsx_pci_write_register(pcr, SD_BUS_STAT, SD_CLK_TOGGLE_EN, SD_CLK_TOGGLE_EN);
> +
> if (PCI_PID(pcr) == PID_5261) {
> /*
> * If test mode is set switch to SD Express mandatorily,
> @@ -968,7 +975,8 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
> }
> }
>
> - host->power_state = SDMMC_POWER_ON;
> +finish:
> + host->prev_power_state = power_mode;
> return 0;
> }
>
> @@ -977,7 +985,7 @@ static int sd_power_off(struct realtek_pci_sdmmc *host)
> struct rtsx_pcr *pcr = host->pcr;
> int err;
>
> - host->power_state = SDMMC_POWER_OFF;
> + host->prev_power_state = MMC_POWER_OFF;
>
> rtsx_pci_init_cmd(pcr);
>
> @@ -1003,7 +1011,7 @@ static int sd_set_power_mode(struct realtek_pci_sdmmc *host,
> if (power_mode == MMC_POWER_OFF)
> err = sd_power_off(host);
> else
> - err = sd_power_on(host);
> + err = sd_power_on(host, power_mode);
>
> return err;
> }
> @@ -1506,10 +1514,11 @@ static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
>
> host = mmc_priv(mmc);
> host->pcr = pcr;
> + mmc->ios.power_delay_ms = 5;
> host->mmc = mmc;
> host->pdev = pdev;
> host->cookie = -1;
> - host->power_state = SDMMC_POWER_OFF;
> + host->prev_power_state = MMC_POWER_OFF;
> INIT_WORK(&host->work, sd_request);
> platform_set_drvdata(pdev, host);
> pcr->slots[RTSX_SD_CARD].p_dev = pdev;
> --
> 2.25.1