Re: [PATCH 2/2] [v2] qcom_scm: hide Kconfig symbol

Bjorn Andersson
2021-09-29T14:50:57Z

On Tue 28 Sep 02:50 CDT 2021, Arnd Bergmann wrote:

> From: Arnd Bergmann <arnd@arndb.de>
>
> Now that SCM can be a loadable module, we have to add another
> dependency to avoid link failures when ipa or adreno-gpu are
> built-in:
>
> aarch64-linux-ld: drivers/net/ipa/ipa_main.o: in function `ipa_probe':
> ipa_main.c:(.text+0xfc4): undefined reference to `qcom_scm_is_available'
>
> ld.lld: error: undefined symbol: qcom_scm_is_available
> >>> referenced by adreno_gpu.c
> >>> gpu/drm/msm/adreno/adreno_gpu.o:(adreno_zap_shader_load) in archive drivers/built-in.a
>
> This can happen when CONFIG_ARCH_QCOM is disabled and we don't select
> QCOM_MDT_LOADER, but some other module selects QCOM_SCM. Ideally we'd
> use a similar dependency here to what we have for QCOM_RPROC_COMMON,
> but that causes dependency loops from other things selecting QCOM_SCM.
>
> This appears to be an endless problem, so try something different this
> time:
>
> - CONFIG_QCOM_SCM becomes a hidden symbol that nothing 'depends on'
> but that is simply selected by all of its users
>
> - All the stubs in include/linux/qcom_scm.h can go away
>
> - arm-smccc.h needs to provide a stub for __arm_smccc_smc() to
> allow compile-testing QCOM_SCM on all architectures.
>
> - To avoid a circular dependency chain involving RESET_CONTROLLER
> and PINCTRL_SUNXI, drop the 'select RESET_CONTROLLER' statement.
> According to my testing this still builds fine, and the QCOM
> platform selects this symbol already.
>
> Acked-by: Kalle Valo <kvalo@codeaurora.org>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> Changes in v2:
> - drop the 'select RESET_CONTROLLER' line, rather than adding
> more of the same
> ---
> drivers/firmware/Kconfig | 5 +-
> drivers/gpu/drm/msm/Kconfig | 4 +-
> drivers/iommu/Kconfig | 2 +-
> drivers/media/platform/Kconfig | 2 +-
> drivers/mmc/host/Kconfig | 2 +-
> drivers/net/ipa/Kconfig | 1 +
> drivers/net/wireless/ath/ath10k/Kconfig | 2 +-
> drivers/pinctrl/qcom/Kconfig | 3 +-
> include/linux/arm-smccc.h | 10 ++++
> include/linux/qcom_scm.h | 71 -------------------------
> 10 files changed, 20 insertions(+), 82 deletions(-)
>
> diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig
> index 220a58cf0a44..cda7d7162cbb 100644
> --- a/drivers/firmware/Kconfig
> +++ b/drivers/firmware/Kconfig
> @@ -203,10 +203,7 @@ config INTEL_STRATIX10_RSU
> Say Y here if you want Intel RSU support.
>
> config QCOM_SCM
> - tristate "Qcom SCM driver"
> - depends on ARM || ARM64
> - depends on HAVE_ARM_SMCCC
> - select RESET_CONTROLLER
> + tristate
>
> config QCOM_SCM_DOWNLOAD_MODE_DEFAULT
> bool "Qualcomm download mode enabled by default"
> diff --git a/drivers/gpu/drm/msm/Kconfig b/drivers/gpu/drm/msm/Kconfig
> index e9c6af78b1d7..3ddf739a6f9b 100644
> --- a/drivers/gpu/drm/msm/Kconfig
> +++ b/drivers/gpu/drm/msm/Kconfig
> @@ -17,7 +17,7 @@ config DRM_MSM
> select DRM_SCHED
> select SHMEM
> select TMPFS
> - select QCOM_SCM if ARCH_QCOM
> + select QCOM_SCM
> select WANT_DEV_COREDUMP
> select SND_SOC_HDMI_CODEC if SND_SOC
> select SYNC_FILE
> @@ -55,7 +55,7 @@ config DRM_MSM_GPU_SUDO
>
> config DRM_MSM_HDMI_HDCP
> bool "Enable HDMI HDCP support in MSM DRM driver"
> - depends on DRM_MSM && QCOM_SCM
> + depends on DRM_MSM
> default y
> help
> Choose this option to enable HDCP state machine
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index 124c41adeca1..989c83acbfee 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -308,7 +308,7 @@ config APPLE_DART
> config ARM_SMMU
> tristate "ARM Ltd. System MMU (SMMU) Support"
> depends on ARM64 || ARM || (COMPILE_TEST && !GENERIC_ATOMIC64)
> - depends on QCOM_SCM || !QCOM_SCM #if QCOM_SCM=m this can't be =y
> + select QCOM_SCM
> select IOMMU_API
> select IOMMU_IO_PGTABLE_LPAE
> select ARM_DMA_USE_IOMMU if ARM

As noted in the RFC, I think you also need to fix QCOM_IOMMU.

In particular (iirc) since all the users of the iommu might be modules,
which would prevent QCOM_IOMMU from being selected.

The rest looks good.

Regards,
Bjorn

> diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig
> index 157c924686e4..80321e03809a 100644
> --- a/drivers/media/platform/Kconfig
> +++ b/drivers/media/platform/Kconfig
> @@ -565,7 +565,7 @@ config VIDEO_QCOM_VENUS
> depends on VIDEO_DEV && VIDEO_V4L2 && QCOM_SMEM
> depends on (ARCH_QCOM && IOMMU_DMA) || COMPILE_TEST
> select QCOM_MDT_LOADER if ARCH_QCOM
> - select QCOM_SCM if ARCH_QCOM
> + select QCOM_SCM
> select VIDEOBUF2_DMA_CONTIG
> select V4L2_MEM2MEM_DEV
> help
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index 71313961cc54..95b3511b0560 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -547,7 +547,7 @@ config MMC_SDHCI_MSM
> depends on MMC_SDHCI_PLTFM
> select MMC_SDHCI_IO_ACCESSORS
> select MMC_CQHCI
> - select QCOM_SCM if MMC_CRYPTO && ARCH_QCOM
> + select QCOM_SCM 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/net/ipa/Kconfig b/drivers/net/ipa/Kconfig
> index 8f99cfa14680..d037682fb7ad 100644
> --- a/drivers/net/ipa/Kconfig
> +++ b/drivers/net/ipa/Kconfig
> @@ -4,6 +4,7 @@ config QCOM_IPA
> depends on ARCH_QCOM || COMPILE_TEST
> depends on QCOM_RPROC_COMMON || (QCOM_RPROC_COMMON=n && COMPILE_TEST)
> select QCOM_MDT_LOADER if ARCH_QCOM
> + select QCOM_SCM
> select QCOM_QMI_HELPERS
> help
> Choose Y or M here to include support for the Qualcomm
> diff --git a/drivers/net/wireless/ath/ath10k/Kconfig b/drivers/net/wireless/ath/ath10k/Kconfig
> index 741289e385d5..ca007b800f75 100644
> --- a/drivers/net/wireless/ath/ath10k/Kconfig
> +++ b/drivers/net/wireless/ath/ath10k/Kconfig
> @@ -44,7 +44,7 @@ config ATH10K_SNOC
> tristate "Qualcomm ath10k SNOC support"
> depends on ATH10K
> depends on ARCH_QCOM || COMPILE_TEST
> - depends on QCOM_SCM || !QCOM_SCM #if QCOM_SCM=m this can't be =y
> + select QCOM_SCM
> select QCOM_QMI_HELPERS
> help
> This module adds support for integrated WCN3990 chip connected
> diff --git a/drivers/pinctrl/qcom/Kconfig b/drivers/pinctrl/qcom/Kconfig
> index 32ea2a8ec02b..5ff4207df66e 100644
> --- a/drivers/pinctrl/qcom/Kconfig
> +++ b/drivers/pinctrl/qcom/Kconfig
> @@ -3,7 +3,8 @@ if (ARCH_QCOM || COMPILE_TEST)
>
> config PINCTRL_MSM
> tristate "Qualcomm core pin controller driver"
> - depends on GPIOLIB && (QCOM_SCM || !QCOM_SCM) #if QCOM_SCM=m this can't be =y
> + depends on GPIOLIB
> + select QCOM_SCM
> select PINMUX
> select PINCONF
> select GENERIC_PINCONF
> diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
> index 7d1cabe15262..63ccb5252190 100644
> --- a/include/linux/arm-smccc.h
> +++ b/include/linux/arm-smccc.h
> @@ -321,10 +321,20 @@ asmlinkage unsigned long __arm_smccc_sve_check(unsigned long x0);
> * from register 0 to 3 on return from the SMC instruction. An optional
> * quirk structure provides vendor specific behavior.
> */
> +#ifdef CONFIG_HAVE_ARM_SMCCC
> asmlinkage void __arm_smccc_smc(unsigned long a0, unsigned long a1,
> unsigned long a2, unsigned long a3, unsigned long a4,
> unsigned long a5, unsigned long a6, unsigned long a7,
> struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
> +#else
> +static inline void __arm_smccc_smc(unsigned long a0, unsigned long a1,
> + unsigned long a2, unsigned long a3, unsigned long a4,
> + unsigned long a5, unsigned long a6, unsigned long a7,
> + struct arm_smccc_res *res, struct arm_smccc_quirk *quirk)
> +{
> + *res = (struct arm_smccc_res){};
> +}
> +#endif
>
> /**
> * __arm_smccc_hvc() - make HVC calls
> diff --git a/include/linux/qcom_scm.h b/include/linux/qcom_scm.h
> index c0475d1c9885..81cad9e1e412 100644
> --- a/include/linux/qcom_scm.h
> +++ b/include/linux/qcom_scm.h
> @@ -61,7 +61,6 @@ enum qcom_scm_ice_cipher {
> #define QCOM_SCM_PERM_RW (QCOM_SCM_PERM_READ | QCOM_SCM_PERM_WRITE)
> #define QCOM_SCM_PERM_RWX (QCOM_SCM_PERM_RW | QCOM_SCM_PERM_EXEC)
>
> -#if IS_ENABLED(CONFIG_QCOM_SCM)
> extern bool qcom_scm_is_available(void);
>
> extern int qcom_scm_set_cold_boot_addr(void *entry, const cpumask_t *cpus);
> @@ -115,74 +114,4 @@ extern int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
> extern int qcom_scm_lmh_profile_change(u32 profile_id);
> extern bool qcom_scm_lmh_dcvsh_available(void);
>
> -#else
> -
> -#include <linux/errno.h>
> -
> -static inline bool qcom_scm_is_available(void) { return false; }
> -
> -static inline int qcom_scm_set_cold_boot_addr(void *entry,
> - const cpumask_t *cpus) { return -ENODEV; }
> -static inline int qcom_scm_set_warm_boot_addr(void *entry,
> - const cpumask_t *cpus) { return -ENODEV; }
> -static inline void qcom_scm_cpu_power_down(u32 flags) {}
> -static inline u32 qcom_scm_set_remote_state(u32 state,u32 id)
> - { return -ENODEV; }
> -
> -static inline int qcom_scm_pas_init_image(u32 peripheral, const void *metadata,
> - size_t size) { return -ENODEV; }
> -static inline int qcom_scm_pas_mem_setup(u32 peripheral, phys_addr_t addr,
> - phys_addr_t size) { return -ENODEV; }
> -static inline int qcom_scm_pas_auth_and_reset(u32 peripheral)
> - { return -ENODEV; }
> -static inline int qcom_scm_pas_shutdown(u32 peripheral) { return -ENODEV; }
> -static inline bool qcom_scm_pas_supported(u32 peripheral) { return false; }
> -
> -static inline int qcom_scm_io_readl(phys_addr_t addr, unsigned int *val)
> - { return -ENODEV; }
> -static inline int qcom_scm_io_writel(phys_addr_t addr, unsigned int val)
> - { return -ENODEV; }
> -
> -static inline bool qcom_scm_restore_sec_cfg_available(void) { return false; }
> -static inline int qcom_scm_restore_sec_cfg(u32 device_id, u32 spare)
> - { return -ENODEV; }
> -static inline int qcom_scm_iommu_secure_ptbl_size(u32 spare, size_t *size)
> - { return -ENODEV; }
> -static inline int qcom_scm_iommu_secure_ptbl_init(u64 addr, u32 size, u32 spare)
> - { return -ENODEV; }
> -extern inline int qcom_scm_mem_protect_video_var(u32 cp_start, u32 cp_size,
> - u32 cp_nonpixel_start,
> - u32 cp_nonpixel_size)
> - { return -ENODEV; }
> -static inline int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
> - unsigned int *src, const struct qcom_scm_vmperm *newvm,
> - unsigned int dest_cnt) { return -ENODEV; }
> -
> -static inline bool qcom_scm_ocmem_lock_available(void) { return false; }
> -static inline int qcom_scm_ocmem_lock(enum qcom_scm_ocmem_client id, u32 offset,
> - u32 size, u32 mode) { return -ENODEV; }
> -static inline int qcom_scm_ocmem_unlock(enum qcom_scm_ocmem_client id,
> - u32 offset, u32 size) { return -ENODEV; }
> -
> -static inline bool qcom_scm_ice_available(void) { return false; }
> -static inline int qcom_scm_ice_invalidate_key(u32 index) { return -ENODEV; }
> -static inline int qcom_scm_ice_set_key(u32 index, const u8 *key, u32 key_size,
> - enum qcom_scm_ice_cipher cipher,
> - u32 data_unit_size) { return -ENODEV; }
> -
> -static inline bool qcom_scm_hdcp_available(void) { return false; }
> -static inline int qcom_scm_hdcp_req(struct qcom_scm_hdcp_req *req, u32 req_cnt,
> - u32 *resp) { return -ENODEV; }
> -
> -static inline int qcom_scm_qsmmu500_wait_safe_toggle(bool en)
> - { return -ENODEV; }
> -
> -static inline int qcom_scm_lmh_dcvsh(u32 payload_fn, u32 payload_reg, u32 payload_val,
> - u64 limit_node, u32 node_id, u64 version)
> - { return -ENODEV; }
> -
> -static inline int qcom_scm_lmh_profile_change(u32 profile_id) { return -ENODEV; }
> -
> -static inline bool qcom_scm_lmh_dcvsh_available(void) { return -ENODEV; }
> -#endif
> #endif
> --
> 2.29.2
>