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SubjectRe: [PATCH V5 14/26] mmc: sdhci-uhs2: add set_timeout()
On 19/10/22 14:06, Victor Shih wrote:
> From: AKASHI Takahiro <takahiro.akashi@linaro.org>
>
> This is a UHS-II version of sdhci's set_timeout() operation.
>
> Signed-off-by: Ben Chuang <ben.chuang@genesyslogic.com.tw>
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> ---
> drivers/mmc/host/sdhci-uhs2.c | 85 +++++++++++++++++++++++++++++++++++
> drivers/mmc/host/sdhci-uhs2.h | 1 +
> 2 files changed, 86 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-uhs2.c b/drivers/mmc/host/sdhci-uhs2.c
> index 4dc3e904d7d2..2b90e5308764 100644
> --- a/drivers/mmc/host/sdhci-uhs2.c
> +++ b/drivers/mmc/host/sdhci-uhs2.c
> @@ -196,6 +196,91 @@ void sdhci_uhs2_set_power(struct sdhci_host *host, unsigned char mode,
> }
> EXPORT_SYMBOL_GPL(sdhci_uhs2_set_power);
>
> +static u8 sdhci_calc_timeout_uhs2(struct sdhci_host *host, u8 *cmd_res,
> + u8 *dead_lock)
> +{
> + u8 count;
> + unsigned int cmd_res_timeout, dead_lock_timeout, current_timeout;
> +
> + /*
> + * If the host controller provides us with an incorrect timeout
> + * value, just skip the check and use 0xE. The hardware may take
> + * longer to time out, but that's much better than having a too-short
> + * timeout value.
> + */
> + if (host->quirks & SDHCI_QUIRK_BROKEN_TIMEOUT_VAL) {
> + *cmd_res = 0xE;
> + *dead_lock = 0xE;
> + return 0xE;
> + }

Let's skip quirks you don't need for now.

> +
> + /* timeout in us */
> + cmd_res_timeout = 5 * 1000;
> + dead_lock_timeout = 1 * 1000 * 1000;
> +
> + /*
> + * Figure out needed cycles.
> + * We do this in steps in order to fit inside a 32 bit int.
> + * The first step is the minimum timeout, which will have a
> + * minimum resolution of 6 bits:
> + * (1) 2^13*1000 > 2^22,
> + * (2) host->timeout_clk < 2^16
> + * =>
> + * (1) / (2) > 2^6
> + */
> + count = 0;
> + current_timeout = (1 << 13) * 1000 / host->timeout_clk;
> + while (current_timeout < cmd_res_timeout) {
> + count++;
> + current_timeout <<= 1;
> + if (count >= 0xF)
> + break;
> + }
> +
> + if (count >= 0xF) {
> + DBG("%s: Too large timeout 0x%x requested for CMD_RES!\n",
> + mmc_hostname(host->mmc), count);
> + count = 0xE;
> + }
> + *cmd_res = count;
> +
> + count = 0;
> + current_timeout = (1 << 13) * 1000 / host->timeout_clk;
> + while (current_timeout < dead_lock_timeout) {
> + count++;
> + current_timeout <<= 1;
> + if (count >= 0xF)
> + break;
> + }
> +
> + if (count >= 0xF) {
> + DBG("%s: Too large timeout 0x%x requested for DEADLOCK!\n",
> + mmc_hostname(host->mmc), count);
> + count = 0xE;
> + }
> + *dead_lock = count;
> +
> + return count;
> +}
> +
> +static void __sdhci_uhs2_set_timeout(struct sdhci_host *host)
> +{
> + u8 cmd_res, dead_lock;
> +
> + sdhci_calc_timeout_uhs2(host, &cmd_res, &dead_lock);
> + cmd_res |= dead_lock << SDHCI_UHS2_TIMER_CTRL_DEADLOCK_SHIFT;

GENMASK() and FIELD_PREP() please

> + sdhci_writeb(host, cmd_res, SDHCI_UHS2_TIMER_CTRL);
> +}
> +
> +void sdhci_uhs2_set_timeout(struct sdhci_host *host, struct mmc_command *cmd)
> +{
> + __sdhci_set_timeout(host, cmd);
> +
> + if (host->mmc->flags & MMC_UHS2_SUPPORT)

if (sdhci_uhs2_mode(host))

> + __sdhci_uhs2_set_timeout(host);
> +}
> +EXPORT_SYMBOL_GPL(sdhci_uhs2_set_timeout);
> +
> /*****************************************************************************\
> * *
> * MMC callbacks *
> diff --git a/drivers/mmc/host/sdhci-uhs2.h b/drivers/mmc/host/sdhci-uhs2.h
> index 3179915f7f79..5ea235b14108 100644
> --- a/drivers/mmc/host/sdhci-uhs2.h
> +++ b/drivers/mmc/host/sdhci-uhs2.h
> @@ -215,5 +215,6 @@ bool sdhci_uhs2_mode(struct sdhci_host *host);
> void sdhci_uhs2_reset(struct sdhci_host *host, u16 mask);
> void sdhci_uhs2_set_power(struct sdhci_host *host, unsigned char mode,
> unsigned short vdd);
> +void sdhci_uhs2_set_timeout(struct sdhci_host *host, struct mmc_command *cmd);
>
> #endif /* __SDHCI_UHS2_H */

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