* RE: [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1
2024-04-12 19:26 ` [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1 curtis.machida
@ 2024-04-15 9:59 ` Jaehoon Chung
2024-04-15 14:47 ` Sean Anderson
1 sibling, 0 replies; 3+ messages in thread
From: Jaehoon Chung @ 2024-04-15 9:59 UTC (permalink / raw)
To: curtis.machida, u-boot, 'Peng Fan'
Cc: 'Jonas Karlman', 'Kever Yang',
'Peter Geis', 'Sean Anderson',
'Simon Glass', 'Tom Rini'
> -----Original Message-----
> From: curtis.machida@intel.com <curtis.machida@intel.com>
> Sent: Saturday, April 13, 2024 4:27 AM
> To: u-boot@lists.denx.de; Peng Fan <peng.fan@nxp.com>; Jaehoon Chung <jh80.chung@samsung.com>
> Cc: cmachida <curtis.machida@intel.com>; Jonas Karlman <jonas@kwiboo.se>; Kever Yang <kever.yang@rock-
> chips.com>; Peter Geis <pgwipeout@gmail.com>; Sean Anderson <sean.anderson@seco.com>; Simon Glass
> <sjg@chromium.org>; Tom Rini <trini@konsulko.com>
> Subject: [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1
>
> From: cmachida <curtis.machida@intel.com>
>
> 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 <curtis.machida@intel.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
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
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1
2024-04-12 19:26 ` [PATCH] mmc: sdhci: programmable clock calculation needs multiplier +1 curtis.machida
2024-04-15 9:59 ` Jaehoon Chung
@ 2024-04-15 14:47 ` Sean Anderson
1 sibling, 0 replies; 3+ messages in thread
From: Sean Anderson @ 2024-04-15 14:47 UTC (permalink / raw)
To: curtis.machida, u-boot, Peng Fan, Jaehoon Chung
Cc: Jonas Karlman, Kever Yang, Peter Geis, Simon Glass, Tom Rini
On 4/12/24 15:26, curtis.machida@intel.com wrote:
> [You don't often get email from curtis.machida@intel.com. Learn why this is important at https://cas5-0-urlprotect.trendmicro.com:443/wis/clicktime/v1/query?url=https%3a%2f%2faka.ms%2fLearnAboutSenderIdentification&umid=4f25273f-b33b-4eb3-8643-c1f6eff8842b&auth=d807158c60b7d2502abde8a2fc01f40662980862-c95c2e418b830130ad99c91e42b2732e3f7e44ee ]
>
> From: cmachida <curtis.machida@intel.com>
>
> 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 <curtis.machida@intel.com>
> ---
>
> 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 <sean.anderson@seco.com>
^ permalink raw reply [flat|nested] 3+ messages in thread