[PATCH v5 2/2] mmc: add new sdhci reset sequence for brcm 74165b0

Florian Fainelli florian.fainelli at broadcom.com
Tue Dec 19 13:55:38 PST 2023


Hi Kamal,

On 12/19/2023 5:22 PM, Kamal Dasu wrote:
> From: Kamal Dasu <kdasu at broadcom.com>
> 
> 74165b0 shall use a new sdio controller core version which
> requires a different reset sequence. For core reset we use
> sdhci_reset. For CMD and/or DATA reset added a new function
> to also enable SDHCI clocks SDHCI_CLOCK_CARD_EN
> SDHCI_CLOCK_INT_EN along with the SDHCI_RESET_CMD and/or
> SDHCI_RESET_DATA fields.
> 
> Signed-off-by: Kamal Dasu <kdasu at broadcom.com>
> ---

[snip]

> +static void brcmstb_sdhci_reset_cmd_data(struct sdhci_host *host, u8 mask)
> +{
> +	int ret;
> +	u32 reg;
> +	u32 new_mask = (mask &  (SDHCI_RESET_CMD | SDHCI_RESET_DATA)) << 24;
> +
> +	/*
> +	 * SDHCI_CLOCK_CONTROL register CARD_EN and CLOCK_INT_EN bits shall
> +	 * be set along with SOFTWARE_RESET register RESET_CMD or RESET_DATA
> +	 * bits, hence access SDHCI_CLOCK_CONTROL register as 32-bit register
> +	 */
> +	new_mask |= SDHCI_CLOCK_CARD_EN | SDHCI_CLOCK_INT_EN;
> +	reg = sdhci_readl(host, SDHCI_CLOCK_CONTROL);
> +	sdhci_writel(host, reg | new_mask, SDHCI_CLOCK_CONTROL);
> +
> +	reg = sdhci_readb(host, SDHCI_SOFTWARE_RESET);
> +	ret = readb_poll_timeout(host->ioaddr + SDHCI_SOFTWARE_RESET,
> +				 reg, reg & mask, 10, 10000);

Does this need to be readb_poll_timeout_atomic() since this function can 
be used in both atomic and non-atomic context AFAIR?
-- 
Florian
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