openwrt/target/linux/bcm27xx/patches-6.6/950-0981-drivers-sdhci-brcmstb-set-CQE-timer-clock-frequency.patch

From 337caf7170e9cd721c0903c46e56bc05fb5b625d Mon Sep 17 00:00:00 2001
From: Jonathan Bell <jonathan@raspberrypi.com>
Date: Wed, 20 Mar 2024 10:59:10 +0000
Subject: [PATCH 0981/1085] drivers: sdhci-brcmstb: set CQE timer clock
 frequency

CQHCI keeps track of tags in flight with internal timers, so the clock
frequency driving the timer needs to be specified. The config registers
default to 0 (100kHz) which means timeouts will be significantly shorter
than they should be. Assume the timer clock comes from the controller
base clock.

Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
---
 drivers/mmc/host/sdhci-brcmstb.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

--- a/drivers/mmc/host/sdhci-brcmstb.c
+++ b/drivers/mmc/host/sdhci-brcmstb.c
@@ -42,6 +42,9 @@
 #define  SDIO_CFG_SD_PIN_SEL_SD			BIT(1)
 #define  SDIO_CFG_SD_PIN_SEL_MMC		BIT(0)
 
+#define SDIO_CFG_CQ_CAPABILITY			0x4c
+#define  SDIO_CFG_CQ_CAPABILITY_FMUL_SHIFT	12
+
 #define SDIO_CFG_MAX_50MHZ_MODE			0x1ac
 #define  SDIO_CFG_MAX_50MHZ_MODE_STRAP_OVERRIDE	BIT(31)
 #define  SDIO_CFG_MAX_50MHZ_MODE_ENABLE		BIT(0)
@@ -202,7 +205,7 @@ static void sdhci_brcmstb_cfginit_2712(s
 	u32 uhs_mask = (MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_SDR104);
 	u32 hsemmc_mask = (MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS200_1_2V_SDR |
 			   MMC_CAP2_HS400_1_8V | MMC_CAP2_HS400_1_2V);
-	u32 reg;
+	u32 reg, base_clk_mhz;
 
 	/*
 	* If we support a speed that requires tuning,
@@ -223,6 +226,11 @@ static void sdhci_brcmstb_cfginit_2712(s
 		reg |= SDIO_CFG_CTRL_SDCD_N_TEST_EN;
 		writel(reg, brcmstb_priv->cfg_regs + SDIO_CFG_CTRL);
 	}
+
+	/* Guesstimate the timer frequency (controller base clock) */
+	base_clk_mhz = max_t(u32, clk_get_rate(pltfm_host->clk) / (1000 * 1000), 1);
+	reg = (3 << SDIO_CFG_CQ_CAPABILITY_FMUL_SHIFT) | base_clk_mhz;
+	writel(reg, brcmstb_priv->cfg_regs + SDIO_CFG_CQ_CAPABILITY);
 }
 
 static int bcm2712_init_sd_express(struct sdhci_host *host, struct mmc_ios *ios)
@@ -494,6 +502,8 @@ static int sdhci_brcmstb_probe(struct pl
 		return PTR_ERR(host);
 
 	pltfm_host = sdhci_priv(host);
+	pltfm_host->clk = clk;
+
 	priv = sdhci_pltfm_priv(pltfm_host);
 	if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
 		priv->flags |= BRCMSTB_PRIV_FLAGS_HAS_CQE;
@@ -627,7 +637,6 @@ add_host:
 	if (res)
 		goto err;
 
-	pltfm_host->clk = clk;
 	return res;
 
 err: