Commit fe86da36 authored by Kamal Dasu's avatar Kamal Dasu Committed by Ulf Hansson
Browse files

mmc: sdhci-brcmstb: add new sdhci reset sequence for brcm 74165b0 



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: default avatarKamal Dasu <kdasu@broadcom.com>
Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20240103222338.31447-3-kamal.dasu@broadcom.com


Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 0a8d397c

drivers/mmc/host/sdhci-brcmstb.c

+64 −5
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
 */



#include <linux/io.h>

#include <linux/iopoll.h>

#include <linux/mmc/host.h>

#include <linux/module.h>

#include <linux/of.h>
@@ -44,8 +45,13 @@ struct brcmstb_match_priv { 


static inline void enable_clock_gating(struct sdhci_host *host)

{

	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);

	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);

	u32 reg;



	if (!(priv->flags & BRCMSTB_PRIV_FLAGS_GATE_CLOCK))

		return;



	reg = sdhci_readl(host, SDHCI_VENDOR);

	reg |= SDHCI_VENDOR_GATE_SDCLK_EN;

	sdhci_writel(host, reg, SDHCI_VENDOR);
@@ -53,13 +59,52 @@ static inline void enable_clock_gating(struct sdhci_host *host) 


static void brcmstb_reset(struct sdhci_host *host, u8 mask)

{

	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);

	struct sdhci_brcmstb_priv *priv = sdhci_pltfm_priv(pltfm_host);



	sdhci_and_cqhci_reset(host, mask);



	/* Reset will clear this, so re-enable it */

	if (priv->flags & BRCMSTB_PRIV_FLAGS_GATE_CLOCK)

	enable_clock_gating(host);

}



static void brcmstb_sdhci_reset_cmd_data(struct sdhci_host *host, u8 mask)

{

	u32 new_mask = (mask &  (SDHCI_RESET_CMD | SDHCI_RESET_DATA)) << 24;

	int ret;

	u32 reg;



	/*

	 * 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 = read_poll_timeout_atomic(sdhci_readb, reg, !(reg & mask),

				       10, 10000, false,

				       host, SDHCI_SOFTWARE_RESET);



	if (ret) {

		pr_err("%s: Reset 0x%x never completed.\n",

		       mmc_hostname(host->mmc), (int)mask);

		sdhci_err_stats_inc(host, CTRL_TIMEOUT);

		sdhci_dumpregs(host);

	}

}



static void brcmstb_reset_74165b0(struct sdhci_host *host, u8 mask)

{

	/* take care of RESET_ALL as usual */

	if (mask & SDHCI_RESET_ALL)

		sdhci_and_cqhci_reset(host, SDHCI_RESET_ALL);



	/* cmd and/or data treated differently on this core */

	if (mask & (SDHCI_RESET_CMD | SDHCI_RESET_DATA))

		brcmstb_sdhci_reset_cmd_data(host, mask);



	/* Reset will clear this, so re-enable it */

	enable_clock_gating(host);

}
@@ -162,6 +207,13 @@ static struct sdhci_ops sdhci_brcmstb_ops_7216 = { 
	.set_uhs_signaling = sdhci_brcmstb_set_uhs_signaling,

};



static struct sdhci_ops sdhci_brcmstb_ops_74165b0 = {

	.set_clock = sdhci_brcmstb_set_clock,

	.set_bus_width = sdhci_set_bus_width,

	.reset = brcmstb_reset_74165b0,

	.set_uhs_signaling = sdhci_brcmstb_set_uhs_signaling,

};



static struct brcmstb_match_priv match_priv_7425 = {

	.flags = BRCMSTB_MATCH_FLAGS_NO_64BIT |

	BRCMSTB_MATCH_FLAGS_BROKEN_TIMEOUT,
@@ -179,10 +231,17 @@ static const struct brcmstb_match_priv match_priv_7216 = { 
	.ops = &sdhci_brcmstb_ops_7216,

};



static struct brcmstb_match_priv match_priv_74165b0 = {

	.flags = BRCMSTB_MATCH_FLAGS_HAS_CLOCK_GATE,

	.hs400es = sdhci_brcmstb_hs400es,

	.ops = &sdhci_brcmstb_ops_74165b0,

};



static const struct of_device_id __maybe_unused sdhci_brcm_of_match[] = {

	{ .compatible = "brcm,bcm7425-sdhci", .data = &match_priv_7425 },

	{ .compatible = "brcm,bcm7445-sdhci", .data = &match_priv_7445 },

	{ .compatible = "brcm,bcm7216-sdhci", .data = &match_priv_7216 },

	{ .compatible = "brcm,bcm74165b0-sdhci", .data = &match_priv_74165b0 },

	{},

};