[PATCH 0/2] CQE support for cadence eMMC host controller

[PATCH 0/2] CQE support for cadence eMMC host controller

[rohan1sj via B4 Relay]

Add support for Command Queuing Engine(CQE) feature. Supported in
cadence controller but driver lacks the support for it

Signed-off-by: rohan1sj <rohan1sj@cadence.com>
---
rohan1sj (2):
      mmc: cqe: Add CQE DT support for cadence controller
      mmc: cqe: Add CQE support for cadence mmc driver

 .../devicetree/bindings/mmc/cdns,sdhci.yaml        |  32 +++++-
 drivers/mmc/host/sdhci-cadence.c                   | 118 ++++++++++++++++++++-
 2 files changed, 146 insertions(+), 4 deletions(-)
---
base-commit: 05f7e89ab9731565d8a62e3b5d1ec206485eeb0b
change-id: 20260406-cdns_sdhci_cqe-support-41327016d9df

Best regards,
--  
rohan1sj <rohan1sj@cadence.com>

[PATCH 1/2] mmc: cqe: Add CQE DT support for cadence controller

[rohan1sj via B4 Relay]

From: rohan1sj <rohan1sj@cadence.com>

Add DT config required to support CQE as present in
cadence eMMC host controller

Signed-off-by: rohan1sj <rohan1sj@cadence.com>
---
 .../devicetree/bindings/mmc/cdns,sdhci.yaml        | 32 +++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml b/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
index ac75d694611a..c0d8aefe20c2 100644
--- a/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
+++ b/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
@@ -24,6 +24,10 @@ properties:
     minItems: 1
     maxItems: 2
 
+  reg-names:
+    minItems: 1
+    maxItems: 2
+
   interrupts:
     maxItems: 1
 
@@ -139,7 +143,19 @@ allOf:
     else:
       properties:
         reg:
-          maxItems: 1
+          oneOf:
+            - items:
+                - description: Host controller registers
+            - items:
+                - description: Host controller registers
+                - description: CQE (Command Queue Engine) registers
+        reg-names:
+          oneOf:
+            - items:
+                - const: sdhci
+            - items:
+                - const: sdhci
+                - const: cqhci
 
 unevaluatedProperties: false
 
@@ -156,3 +172,17 @@ examples:
         mmc-hs400-1_8v;
         cdns,phy-dll-delay-sdclk = <0>;
     };
+
+  - |
+    emmc_cqe: mmc@5b000000 {
+        compatible = "socionext,uniphier-sd4hc", "cdns,sd4hc";
+        reg = <0x5b000000 0x400>, <0x5b000400 0x060>;
+        reg-names = "sdhci", "cqhci";
+        interrupts = <0 79 4>;
+        clocks = <&clk 4>;
+        bus-width = <8>;
+        mmc-ddr-1_8v;
+        mmc-hs200-1_8v;
+        mmc-hs400-1_8v;
+        cdns,phy-dll-delay-sdclk = <0>;
+    };

-- 
2.34.1

[PATCH 2/2] mmc: cqe: Add CQE support for cadence mmc driver

[rohan1sj via B4 Relay]

From: rohan1sj <rohan1sj@cadence.com>

Add Command Queuing Engine (CQE) support for cadence driver

Signed-off-by: rohan1sj <rohan1sj@cadence.com>
---
 drivers/mmc/host/sdhci-cadence.c | 118 ++++++++++++++++++++++++++++++++++++++-
 1 file changed, 115 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/sdhci-cadence.c b/drivers/mmc/host/sdhci-cadence.c
index 435603c8c00b..14b12272dae9 100644
--- a/drivers/mmc/host/sdhci-cadence.c
+++ b/drivers/mmc/host/sdhci-cadence.c
@@ -15,6 +15,8 @@
 #include <linux/reset.h>
 
 #include "sdhci-pltfm.h"
+#include "sdhci-cqhci.h"
+#include "cqhci.h"
 
 /* HRS - Host Register Set (specific to Cadence) */
 #define SDHCI_CDNS_HRS04		0x10		/* PHY access port */
@@ -36,6 +38,10 @@
 #define   SDHCI_CDNS_HRS06_MODE_MMC_HS400	0x5
 #define   SDHCI_CDNS_HRS06_MODE_MMC_HS400ES	0x6
 
+/* Host capabilities not covered by the standard capability registers (SRS16-SRS18) */
+#define SDHCI_CDNS_HRS30		0x78	/* Host capabilities */
+#define   SDHCI_CDNS_HRS30_CQE_SUPPORTED	BIT(0)
+
 /* Read block gap */
 #define SDHCI_CDNS_HRS37		0x94	/* interface mode select */
 #define   SDHCI_CDNS_HRS37_MODE_DS		0x0
@@ -88,6 +94,7 @@ struct sdhci_cdns_priv {
 	void __iomem *ctl_addr;	/* write control */
 	spinlock_t wrlock;	/* write lock */
 	bool enhanced_strobe;
+	bool cqe_support;   /* Command Queuing Engine support */
 	void (*priv_writel)(struct sdhci_cdns_priv *priv, u32 val, void __iomem *reg);
 	struct reset_control *rst_hw;
 	unsigned int nr_phy_params;
@@ -385,6 +392,73 @@ static void sdhci_cdns_set_uhs_signaling(struct sdhci_host *host,
 		sdhci_set_uhs_signaling(host, timing);
 }
 
+static u32 sdhci_cdns_cqhci_irq(struct sdhci_host *host, u32 intmask)
+{
+	int cmd_err = 0;
+	int data_err = 0;
+
+	/* return original intmask to be handled by other handlers if it's not a CQE interrupt */
+	if (!sdhci_cqe_irq(host, intmask, &cmd_err, &data_err))
+		return intmask;
+
+	cqhci_irq(host->mmc, intmask, cmd_err, data_err);
+
+	return 0;
+}
+
+static const struct cqhci_host_ops sdhci_cdns_cqhci_ops = {
+	.enable		= sdhci_cqe_enable,
+	.disable	= sdhci_cqe_disable,
+};
+
+static int sdhci_cdns_cqe_add_host(struct sdhci_host *host, struct platform_device *pdev)
+{
+	struct cqhci_host *cq_host;
+	bool dma64;
+	int ret;
+
+	/* setup SDHCI host first */
+	ret = sdhci_setup_host(host);
+
+	if (ret)
+		return ret;
+
+	/* Init CQE */
+	cq_host = cqhci_pltfm_init(pdev);
+	if (IS_ERR(cq_host)) {
+		ret = PTR_ERR(cq_host);
+		goto cleanup;
+	}
+
+	dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
+	if (dma64)
+		cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
+
+	cq_host->ops = &sdhci_cdns_cqhci_ops;
+
+	host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
+
+	/* Finally initialize CQHCI */
+	ret = cqhci_init(cq_host, host->mmc, dma64);
+	if (ret) {
+		dev_err(mmc_dev(host->mmc), "Failed to initialize CQHCI: %d\n", ret);
+		goto cleanup;
+	}
+
+	/* add host to MMC subsystem */
+	ret = __sdhci_add_host(host);
+	if (ret)
+		goto cleanup;
+
+	dev_info(mmc_dev(host->mmc), "CQE init: success\n");
+	return 0;
+
+cleanup:
+	dev_err(mmc_dev(host->mmc), "CQE init: failed for %s\n", mmc_hostname(host->mmc));
+	sdhci_cleanup_host(host);
+	return ret;
+}
+
 /* Elba control register bits [6:3] are byte-lane enables */
 #define ELBA_BYTE_ENABLE_MASK(x)	((x) << 3)
 
@@ -474,9 +548,10 @@ static const struct sdhci_ops sdhci_cdns_ops = {
 	.set_clock = sdhci_set_clock,
 	.get_timeout_clock = sdhci_cdns_get_timeout_clock,
 	.set_bus_width = sdhci_set_bus_width,
-	.reset = sdhci_reset,
+	.reset = sdhci_and_cqhci_reset,
 	.platform_execute_tuning = sdhci_cdns_execute_tuning,
 	.set_uhs_signaling = sdhci_cdns_set_uhs_signaling,
+	.irq = sdhci_cdns_cqhci_irq,
 };
 
 static const struct sdhci_cdns_drv_data sdhci_cdns_uniphier_drv_data = {
@@ -553,6 +628,8 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
 	int ret;
 	struct device *dev = &pdev->dev;
 	static const u16 version = SDHCI_SPEC_400 << SDHCI_SPEC_VER_SHIFT;
+	bool cqe_enabled;
+	u32 host_caps;
 
 	clk = devm_clk_get_enabled(dev, NULL);
 	if (IS_ERR(clk))
@@ -608,7 +685,35 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
 			host->mmc_host_ops.card_hw_reset = sdhci_cdns_mmc_hw_reset;
 	}
 
-	return sdhci_add_host(host);
+	host_caps = readl(priv->hrs_addr + SDHCI_CDNS_HRS30);
+	cqe_enabled = host_caps & SDHCI_CDNS_HRS30_CQE_SUPPORTED;
+
+	if (cqe_enabled) {
+		priv->cqe_support = true;
+		ret = sdhci_cdns_cqe_add_host(host, pdev);
+	} else {
+		ret = sdhci_add_host(host);
+	}
+
+	return ret;
+}
+
+static int sdhci_cdns_suspend(struct device *dev)
+{
+	struct sdhci_host *host = dev_get_drvdata(dev);
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_cdns_priv *priv = sdhci_pltfm_priv(pltfm_host);
+	int ret;
+
+	if (priv->cqe_support) {
+		ret = cqhci_suspend(host->mmc);
+		if (ret)
+			return ret;
+	}
+
+	ret = sdhci_pltfm_suspend(dev);
+
+	return ret;
 }
 
 static int sdhci_cdns_resume(struct device *dev)
@@ -630,6 +735,13 @@ static int sdhci_cdns_resume(struct device *dev)
 	if (ret)
 		goto disable_clk;
 
+	/* Resume CQE if enabled */
+	if (priv->cqe_support) {
+		ret = cqhci_resume(host->mmc);
+		if (ret)
+			goto disable_clk;
+	}
+
 	return 0;
 
 disable_clk:
@@ -638,7 +750,7 @@ static int sdhci_cdns_resume(struct device *dev)
 	return ret;
 }
 
-static DEFINE_SIMPLE_DEV_PM_OPS(sdhci_cdns_pm_ops, sdhci_pltfm_suspend, sdhci_cdns_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(sdhci_cdns_pm_ops, sdhci_cdns_suspend, sdhci_cdns_resume);
 
 static const struct of_device_id sdhci_cdns_match[] = {
 	{

-- 
2.34.1

Re: [PATCH 2/2] mmc: cqe: Add CQE support for cadence mmc driver

[Krzysztof Kozlowski]

On 07/04/2026 13:18, rohan1sj via B4 Relay wrote:
> +static int sdhci_cdns_cqe_add_host(struct sdhci_host *host, struct platform_device *pdev)
> +{
> +	struct cqhci_host *cq_host;
> +	bool dma64;
> +	int ret;
> +
> +	/* setup SDHCI host first */
> +	ret = sdhci_setup_host(host);
> +
> +	if (ret)
> +		return ret;
> +
> +	/* Init CQE */
> +	cq_host = cqhci_pltfm_init(pdev);
> +	if (IS_ERR(cq_host)) {
> +		ret = PTR_ERR(cq_host);
> +		goto cleanup;
> +	}
> +
> +	dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
> +	if (dma64)
> +		cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
> +
> +	cq_host->ops = &sdhci_cdns_cqhci_ops;
> +
> +	host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
> +
> +	/* Finally initialize CQHCI */
> +	ret = cqhci_init(cq_host, host->mmc, dma64);
> +	if (ret) {
> +		dev_err(mmc_dev(host->mmc), "Failed to initialize CQHCI: %d\n", ret);

So here error msg

> +		goto cleanup;
> +	}
> +
> +	/* add host to MMC subsystem */
> +	ret = __sdhci_add_host(host);
> +	if (ret)
> +		goto cleanup;
> +
> +	dev_info(mmc_dev(host->mmc), "CQE init: success\n");

dev_dbg

This does not look like useful printk message. Drivers should be silent
on success:
https://elixir.bootlin.com/linux/v6.15-rc7/source/Documentation/process/coding-style.rst#L913
https://elixir.bootlin.com/linux/v6.15-rc7/source/Documentation/process/debugging/driver_development_debugging_guide.rst#L79


> +	return 0;
> +
> +cleanup:
> +	dev_err(mmc_dev(host->mmc), "CQE init: failed for %s\n", mmc_hostname(host->mmc));

And here also error message. Why twice?

And if it is probe path, why aren't you using dev_err_probe()?

Best regards,
Krzysztof

Re: [PATCH 1/2] mmc: cqe: Add CQE DT support for cadence controller

[Krzysztof Kozlowski]

On 07/04/2026 13:18, rohan1sj via B4 Relay wrote:
> From: rohan1sj <rohan1sj@cadence.com>
> 

Please use subject prefixes matching the subsystem. You can get them for
example with `git log --oneline -- DIRECTORY_OR_FILE` on the directory
your patch is touching. For bindings, the preferred subjects are
explained here:
https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patches.html#i-for-patch-submitters


> Add DT config required to support CQE as present in
> cadence eMMC host controller

What is DT config?

Which devices? Say something useful here.

> 
> Signed-off-by: rohan1sj <rohan1sj@cadence.com>

Please use known identity.

> ---
>  .../devicetree/bindings/mmc/cdns,sdhci.yaml        | 32 +++++++++++++++++++++-
>  1 file changed, 31 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml b/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
> index ac75d694611a..c0d8aefe20c2 100644
> --- a/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
> +++ b/Documentation/devicetree/bindings/mmc/cdns,sdhci.yaml
> @@ -24,6 +24,10 @@ properties:
>      minItems: 1
>      maxItems: 2
>  
> +  reg-names:
> +    minItems: 1
> +    maxItems: 2

List would have to be here.

> +
>    interrupts:
>      maxItems: 1
>  
> @@ -139,7 +143,19 @@ allOf:
>      else:
>        properties:
>          reg:
> -          maxItems: 1
> +          oneOf:
> +            - items:
> +                - description: Host controller registers
> +            - items:
> +                - description: Host controller registers
> +                - description: CQE (Command Queue Engine) registers

So just one list with minItems

> +        reg-names:
> +          oneOf:
> +            - items:
> +                - const: sdhci
> +            - items:
> +                - const: sdhci

core

> +                - const: cqhci

cqe

Anyway, reg-names here are pointless. They should be in top-level.

You also need to disallow the reg-names for Pensando, because it has
completely different.

>  
>  unevaluatedProperties: false
>  
> @@ -156,3 +172,17 @@ examples:
>          mmc-hs400-1_8v;
>          cdns,phy-dll-delay-sdclk = <0>;
>      };
> +
> +  - |
> +    emmc_cqe: mmc@5b000000 {
> +        compatible = "socionext,uniphier-sd4hc", "cdns,sd4hc";
> +        reg = <0x5b000000 0x400>, <0x5b000400 0x060>;

No need for new example. Just correct existing one.

Best regards,
Krzysztof