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

Adrian Hunter
2023-03-10T12:45:37Z

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@linaro.org>
> ---
>
> 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 = {