Re: [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1
On 4/12/24 15:26, curtis.mach...@intel.com wrote:
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> ]
>
> From: cmachida
>
> According to the SD Host Controller Simplified Specification v4.20,
> the multiplier value M is one more than the Clock Multiplier field.
>
> Copied code from Linux project. drivers/mmc/host/sdhci.c line 4405
>
> Signed-off-by: cmachida
> ---
>
> drivers/mmc/sdhci.c | 9 +
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
> index 0178ed8a11..a8476ec4e9 100644
> --- a/drivers/mmc/sdhci.c
> +++ b/drivers/mmc/sdhci.c
> @@ -929,6 +929,15 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct
> sdhci_host *host,
> debug("%s, caps_1: 0x%x\n", __func__, caps_1);
> host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>
> SDHCI_CLOCK_MUL_SHIFT;
> +
> + /*
> +* In case the value in Clock Multiplier is 0, then
> programmable
> +* clock mode is not supported, otherwise the actual clock
> +* multiplier is one more than the value of Clock Multiplier
> +* in the Capabilities Register.
> +*/
> + if (host->clk_mul)
> + host->clk_mul += 1;
> }
>
> if (host->max_clk == 0) {
> --
> 2.43.2
>
Reviewed-by: Sean Anderson
RE: [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1
> -Original Message-
> From: curtis.mach...@intel.com
> Sent: Saturday, April 13, 2024 4:27 AM
> To: u-boot@lists.denx.de; Peng Fan ; Jaehoon Chung
>
> Cc: cmachida ; Jonas Karlman ;
> Kever Yang chips.com>; Peter Geis ; Sean Anderson
> ; Simon Glass
> ; Tom Rini
> Subject: [PATCH] mmc: sdhci: programmable clock calculation needs multiplier
> +1
>
> From: cmachida
>
> According to the SD Host Controller Simplified Specification v4.20,
> the multiplier value M is one more than the Clock Multiplier field.
>
> Copied code from Linux project. drivers/mmc/host/sdhci.c line 4405
>
> Signed-off-by: cmachida
Reviewed-by: Jaehoon Chung
Best Regards,
Jaehoon Chung
> ---
>
> drivers/mmc/sdhci.c | 9 +
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
> index 0178ed8a11..a8476ec4e9 100644
> --- a/drivers/mmc/sdhci.c
> +++ b/drivers/mmc/sdhci.c
> @@ -929,6 +929,15 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct
> sdhci_host *host,
> debug("%s, caps_1: 0x%x\n", __func__, caps_1);
> host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>
> SDHCI_CLOCK_MUL_SHIFT;
> +
> + /*
> + * In case the value in Clock Multiplier is 0, then programmable
> + * clock mode is not supported, otherwise the actual clock
> + * multiplier is one more than the value of Clock Multiplier
> + * in the Capabilities Register.
> + */
> + if (host->clk_mul)
> + host->clk_mul += 1;
> }
>
> if (host->max_clk == 0) {
> --
> 2.43.2
[PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1
From: cmachida
According to the SD Host Controller Simplified Specification v4.20,
the multiplier value M is one more than the Clock Multiplier field.
Copied code from Linux project. drivers/mmc/host/sdhci.c line 4405
Signed-off-by: cmachida
---
drivers/mmc/sdhci.c | 9 +
1 file changed, 9 insertions(+)
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 0178ed8a11..a8476ec4e9 100644
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -929,6 +929,15 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct
sdhci_host *host,
debug("%s, caps_1: 0x%x\n", __func__, caps_1);
host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>
SDHCI_CLOCK_MUL_SHIFT;
+
+ /*
+* In case the value in Clock Multiplier is 0, then programmable
+* clock mode is not supported, otherwise the actual clock
+* multiplier is one more than the value of Clock Multiplier
+* in the Capabilities Register.
+*/
+ if (host->clk_mul)
+ host->clk_mul += 1;
}
if (host->max_clk == 0) {
--
2.43.2
