Re: [RFC PATCH v2 6/7] mmc: sdhci-msm: Switch to the new ICE API

[Adrian Hunter]

On 8/03/23 17:58, Abel Vesa wrote:
> Now that there is a new dedicated ICE driver, drop the sdhci-msm ICE
> implementation and use the new ICE api provided by the Qualcomm soc
> driver qcom-ice.
> 
> Signed-off-by: Abel Vesa <abel.vesa@xxxxxxxxxx>
> ---
> 
> Changes since v1:
>  * Added a check for supported algorithm and key size
>    and passed the ICE defined values for algorithm and key size
>  * Added call to evict function
> 
>  drivers/mmc/host/Kconfig     |   2 +-
>  drivers/mmc/host/sdhci-msm.c | 257 +++++------------------------------
>  2 files changed, 33 insertions(+), 226 deletions(-)
> 
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 4745fe217ade..09f837df5435 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -549,7 +549,7 @@ config MMC_SDHCI_MSM
>  	depends on MMC_SDHCI_PLTFM
>  	select MMC_SDHCI_IO_ACCESSORS
>  	select MMC_CQHCI
> -	select QCOM_SCM if MMC_CRYPTO
> +	select QCOM_INLINE_CRYPTO_ENGINE if MMC_CRYPTO
>  	help
>  	  This selects the Secure Digital Host Controller Interface (SDHCI)
>  	  support present in Qualcomm SOCs. The controller supports
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index 8ac81d57a3df..5f00c0695527 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -19,6 +19,8 @@
>  #include <linux/pinctrl/consumer.h>
>  #include <linux/reset.h>
>  
> +#include <soc/qcom/ice.h>
> +
>  #include "sdhci-cqhci.h"
>  #include "sdhci-pltfm.h"
>  #include "cqhci.h"
> @@ -258,12 +260,12 @@ struct sdhci_msm_variant_info {
>  struct sdhci_msm_host {
>  	struct platform_device *pdev;
>  	void __iomem *core_mem;	/* MSM SDCC mapped address */
> -	void __iomem *ice_mem;	/* MSM ICE mapped address (if available) */
>  	int pwr_irq;		/* power irq */
>  	struct clk *bus_clk;	/* SDHC bus voter clock */
>  	struct clk *xo_clk;	/* TCXO clk needed for FLL feature of cm_dll*/
> -	/* core, iface, cal, sleep, and ice clocks */
> -	struct clk_bulk_data bulk_clks[5];
> +	/* core, iface, cal and sleep clocks */
> +	struct clk_bulk_data bulk_clks[4];
> +	struct qcom_ice *ice;
>  	unsigned long clk_rate;
>  	struct mmc_host *mmc;
>  	bool use_14lpp_dll_reset;
> @@ -1802,233 +1804,37 @@ static void sdhci_msm_set_clock(struct sdhci_host *host, unsigned int clock)
>   *                                                                           *
>  \*****************************************************************************/
>  
> -#ifdef CONFIG_MMC_CRYPTO
> -
> -#define AES_256_XTS_KEY_SIZE			64
> -
> -/* QCOM ICE registers */
> -
> -#define QCOM_ICE_REG_VERSION			0x0008
> -
> -#define QCOM_ICE_REG_FUSE_SETTING		0x0010
> -#define QCOM_ICE_FUSE_SETTING_MASK		0x1
> -#define QCOM_ICE_FORCE_HW_KEY0_SETTING_MASK	0x2
> -#define QCOM_ICE_FORCE_HW_KEY1_SETTING_MASK	0x4
> -
> -#define QCOM_ICE_REG_BIST_STATUS		0x0070
> -#define QCOM_ICE_BIST_STATUS_MASK		0xF0000000
> -
> -#define QCOM_ICE_REG_ADVANCED_CONTROL		0x1000
> -
> -#define sdhci_msm_ice_writel(host, val, reg)	\
> -	writel((val), (host)->ice_mem + (reg))
> -#define sdhci_msm_ice_readl(host, reg)	\
> -	readl((host)->ice_mem + (reg))
> -
> -static bool sdhci_msm_ice_supported(struct sdhci_msm_host *msm_host)
> -{
> -	struct device *dev = mmc_dev(msm_host->mmc);
> -	u32 regval = sdhci_msm_ice_readl(msm_host, QCOM_ICE_REG_VERSION);
> -	int major = regval >> 24;
> -	int minor = (regval >> 16) & 0xFF;
> -	int step = regval & 0xFFFF;
> -
> -	/* For now this driver only supports ICE version 3. */
> -	if (major != 3) {
> -		dev_warn(dev, "Unsupported ICE version: v%d.%d.%d\n",
> -			 major, minor, step);
> -		return false;
> -	}
> -
> -	dev_info(dev, "Found QC Inline Crypto Engine (ICE) v%d.%d.%d\n",
> -		 major, minor, step);
> -
> -	/* If fuses are blown, ICE might not work in the standard way. */
> -	regval = sdhci_msm_ice_readl(msm_host, QCOM_ICE_REG_FUSE_SETTING);
> -	if (regval & (QCOM_ICE_FUSE_SETTING_MASK |
> -		      QCOM_ICE_FORCE_HW_KEY0_SETTING_MASK |
> -		      QCOM_ICE_FORCE_HW_KEY1_SETTING_MASK)) {
> -		dev_warn(dev, "Fuses are blown; ICE is unusable!\n");
> -		return false;
> -	}
> -	return true;
> -}
> -
> -static inline struct clk *sdhci_msm_ice_get_clk(struct device *dev)
> -{
> -	return devm_clk_get(dev, "ice");
> -}
> -
> -static int sdhci_msm_ice_init(struct sdhci_msm_host *msm_host,
> -			      struct cqhci_host *cq_host)
> -{
> -	struct mmc_host *mmc = msm_host->mmc;
> -	struct device *dev = mmc_dev(mmc);
> -	struct resource *res;
> -
> -	if (!(cqhci_readl(cq_host, CQHCI_CAP) & CQHCI_CAP_CS))
> -		return 0;
> -
> -	res = platform_get_resource_byname(msm_host->pdev, IORESOURCE_MEM,
> -					   "ice");
> -	if (!res) {
> -		dev_warn(dev, "ICE registers not found\n");
> -		goto disable;
> -	}
> -
> -	if (!qcom_scm_ice_available()) {
> -		dev_warn(dev, "ICE SCM interface not found\n");
> -		goto disable;
> -	}
> -
> -	msm_host->ice_mem = devm_ioremap_resource(dev, res);
> -	if (IS_ERR(msm_host->ice_mem))
> -		return PTR_ERR(msm_host->ice_mem);
> -
> -	if (!sdhci_msm_ice_supported(msm_host))
> -		goto disable;
> -
> -	mmc->caps2 |= MMC_CAP2_CRYPTO;
> -	return 0;
> -
> -disable:
> -	dev_warn(dev, "Disabling inline encryption support\n");
> -	return 0;
> -}
> -
> -static void sdhci_msm_ice_low_power_mode_enable(struct sdhci_msm_host *msm_host)
> -{
> -	u32 regval;
> -
> -	regval = sdhci_msm_ice_readl(msm_host, QCOM_ICE_REG_ADVANCED_CONTROL);
> -	/*
> -	 * Enable low power mode sequence
> -	 * [0]-0, [1]-0, [2]-0, [3]-E, [4]-0, [5]-0, [6]-0, [7]-0
> -	 */
> -	regval |= 0x7000;
> -	sdhci_msm_ice_writel(msm_host, regval, QCOM_ICE_REG_ADVANCED_CONTROL);
> -}
> -
> -static void sdhci_msm_ice_optimization_enable(struct sdhci_msm_host *msm_host)
> -{
> -	u32 regval;
> -
> -	/* ICE Optimizations Enable Sequence */
> -	regval = sdhci_msm_ice_readl(msm_host, QCOM_ICE_REG_ADVANCED_CONTROL);
> -	regval |= 0xD807100;
> -	/* ICE HPG requires delay before writing */
> -	udelay(5);
> -	sdhci_msm_ice_writel(msm_host, regval, QCOM_ICE_REG_ADVANCED_CONTROL);
> -	udelay(5);
> -}
> -
> -/*
> - * Wait until the ICE BIST (built-in self-test) has completed.
> - *
> - * This may be necessary before ICE can be used.
> - *
> - * Note that we don't really care whether the BIST passed or failed; we really
> - * just want to make sure that it isn't still running.  This is because (a) the
> - * BIST is a FIPS compliance thing that never fails in practice, (b) ICE is
> - * documented to reject crypto requests if the BIST fails, so we needn't do it
> - * in software too, and (c) properly testing storage encryption requires testing
> - * the full storage stack anyway, and not relying on hardware-level self-tests.
> - */
> -static int sdhci_msm_ice_wait_bist_status(struct sdhci_msm_host *msm_host)
> -{
> -	u32 regval;
> -	int err;
> -
> -	err = readl_poll_timeout(msm_host->ice_mem + QCOM_ICE_REG_BIST_STATUS,
> -				 regval, !(regval & QCOM_ICE_BIST_STATUS_MASK),
> -				 50, 5000);
> -	if (err)
> -		dev_err(mmc_dev(msm_host->mmc),
> -			"Timed out waiting for ICE self-test to complete\n");
> -	return err;
> -}
> -
> -static void sdhci_msm_ice_enable(struct sdhci_msm_host *msm_host)
> -{
> -	if (!(msm_host->mmc->caps2 & MMC_CAP2_CRYPTO))
> -		return;
> -	sdhci_msm_ice_low_power_mode_enable(msm_host);
> -	sdhci_msm_ice_optimization_enable(msm_host);
> -	sdhci_msm_ice_wait_bist_status(msm_host);
> -}
> -
> -static int __maybe_unused sdhci_msm_ice_resume(struct sdhci_msm_host *msm_host)
> -{
> -	if (!(msm_host->mmc->caps2 & MMC_CAP2_CRYPTO))
> -		return 0;
> -	return sdhci_msm_ice_wait_bist_status(msm_host);
> -}
> -
>  /*
>   * Program a key into a QC ICE keyslot, or evict a keyslot.  QC ICE requires
>   * vendor-specific SCM calls for this; it doesn't support the standard way.
>   */
> +#ifdef CONFIG_MMC_CRYPTO
> +
>  static int sdhci_msm_program_key(struct cqhci_host *cq_host,
>  				 const union cqhci_crypto_cfg_entry *cfg,
>  				 int slot)
>  {
> -	struct device *dev = mmc_dev(cq_host->mmc);
> +	struct sdhci_host *host = mmc_priv(cq_host->mmc);
> +	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> +	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>  	union cqhci_crypto_cap_entry cap;
> -	union {
> -		u8 bytes[AES_256_XTS_KEY_SIZE];
> -		u32 words[AES_256_XTS_KEY_SIZE / sizeof(u32)];
> -	} key;
> -	int i;
> -	int err;
> -
> -	if (!(cfg->config_enable & CQHCI_CRYPTO_CONFIGURATION_ENABLE))
> -		return qcom_scm_ice_invalidate_key(slot);
> +	bool config_enable = cfg->config_enable & CQHCI_CRYPTO_CONFIGURATION_ENABLE;
>  
>  	/* Only AES-256-XTS has been tested so far. */
>  	cap = cq_host->crypto_cap_array[cfg->crypto_cap_idx];
>  	if (cap.algorithm_id != CQHCI_CRYPTO_ALG_AES_XTS ||
> -	    cap.key_size != CQHCI_CRYPTO_KEY_SIZE_256) {
> -		dev_err_ratelimited(dev,
> -				    "Unhandled crypto capability; algorithm_id=%d, key_size=%d\n",
> -				    cap.algorithm_id, cap.key_size);
> +		cap.key_size != CQHCI_CRYPTO_KEY_SIZE_256)
>  		return -EINVAL;
> -	}
> -
> -	memcpy(key.bytes, cfg->crypto_key, AES_256_XTS_KEY_SIZE);
> -
> -	/*
> -	 * The SCM call byte-swaps the 32-bit words of the key.  So we have to
> -	 * do the same, in order for the final key be correct.
> -	 */
> -	for (i = 0; i < ARRAY_SIZE(key.words); i++)
> -		__cpu_to_be32s(&key.words[i]);
> -
> -	err = qcom_scm_ice_set_key(slot, key.bytes, AES_256_XTS_KEY_SIZE,
> -				   QCOM_SCM_ICE_CIPHER_AES_256_XTS,
> -				   cfg->data_unit_size);
> -	memzero_explicit(&key, sizeof(key));
> -	return err;
> -}
> -#else /* CONFIG_MMC_CRYPTO */
> -static inline struct clk *sdhci_msm_ice_get_clk(struct device *dev)
> -{
> -	return NULL;
> -}
> -
> -static inline int sdhci_msm_ice_init(struct sdhci_msm_host *msm_host,
> -				     struct cqhci_host *cq_host)
> -{
> -	return 0;
> -}
> -
> -static inline void sdhci_msm_ice_enable(struct sdhci_msm_host *msm_host)
> -{
> -}
>  
> -static inline int __maybe_unused
> -sdhci_msm_ice_resume(struct sdhci_msm_host *msm_host)
> -{
> -	return 0;
> +	if (config_enable)
> +		return qcom_ice_program_key(msm_host->ice,
> +					    cfg->crypto_cap_idx,
> +					    QCOM_ICE_CRYPTO_ALG_AES_XTS,
> +					    QCOM_ICE_CRYPTO_KEY_SIZE_256,
> +					    cfg->crypto_key,
> +					    cfg->data_unit_size, slot);
> +	else
> +		return qcom_ice_evict_key(msm_host->ice, slot);
>  }
>  #endif /* !CONFIG_MMC_CRYPTO */
>  
> @@ -2057,7 +1863,7 @@ static void sdhci_msm_cqe_enable(struct mmc_host *mmc)
>  	struct sdhci_msm_host *msm_host = sdhci_pltfm_priv(pltfm_host);
>  
>  	sdhci_cqe_enable(mmc);
> -	sdhci_msm_ice_enable(msm_host);
> +	qcom_ice_enable(msm_host->ice);
>  }
>  
>  static void sdhci_msm_cqe_disable(struct mmc_host *mmc, bool recovery)
> @@ -2149,9 +1955,13 @@ static int sdhci_msm_cqe_add_host(struct sdhci_host *host,
>  
>  	dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
>  
> -	ret = sdhci_msm_ice_init(msm_host, cq_host);
> -	if (ret)
> -		goto cleanup;
> +	if (cqhci_readl(cq_host, CQHCI_CAP) & CQHCI_CAP_CS) {
> +		msm_host->ice = of_qcom_ice_get(&pdev->dev);
> +		if (IS_ERR(msm_host->ice)) {
> +			ret = PTR_ERR(msm_host->ice);
> +			goto cleanup;
> +		}
> +	}

I made a comment before, but more explicitly:

Please retain the wrappers sdhci_msm_ice_enable(),
sdhci_msm_ice_init() and sdhci_msm_ice_resume(),
and the CONFIG_MMC_CRYPTO conditional compilation
around them.

>  
>  	ret = cqhci_init(cq_host, host->mmc, dma64);
>  	if (ret) {
> @@ -2630,11 +2440,6 @@ static int sdhci_msm_probe(struct platform_device *pdev)
>  		clk = NULL;
>  	msm_host->bulk_clks[3].clk = clk;
>  
> -	clk = sdhci_msm_ice_get_clk(&pdev->dev);
> -	if (IS_ERR(clk))
> -		clk = NULL;
> -	msm_host->bulk_clks[4].clk = clk;
> -
>  	ret = clk_bulk_prepare_enable(ARRAY_SIZE(msm_host->bulk_clks),
>  				      msm_host->bulk_clks);
>  	if (ret)
> @@ -2853,7 +2658,9 @@ static __maybe_unused int sdhci_msm_runtime_resume(struct device *dev)
>  
>  	dev_pm_opp_set_rate(dev, msm_host->clk_rate);
>  
> -	return sdhci_msm_ice_resume(msm_host);
> +	if (!(msm_host->mmc->caps2 & MMC_CAP2_CRYPTO))
> +		return 0;
> +	return qcom_ice_resume(msm_host->ice);
>  }
>  
>  static const struct dev_pm_ops sdhci_msm_pm_ops = {