From: Suzuki K Poulose <suzuki.poulose@arm.com> mainline inclusion from mainline-v6.13-rc1 commit 371589437616fbb03590d8ff505f8a4c95c8a031 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IBWQ24 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- On Arm CCA, with RMM-v1.0, all MMIO regions are shared. However, in the future, an Arm CCA-v1.0 compliant guest may be run in a lesser privileged partition in the Realm World (with Arm CCA-v1.1 Planes feature). In this case, some of the MMIO regions may be emulated by a higher privileged component in the Realm world, i.e, protected. Thus the guest must decide today, whether a given MMIO region is shared vs Protected and create the stage1 mapping accordingly. On Arm CCA, this detection is based on the "IPA State" (RIPAS == RIPAS_IO). Provide a helper to run this check on a given range of MMIO. Also, provide a arm64 helper which may be hooked in by other solutions. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Steven Price <steven.price@arm.com> Link: https://lore.kernel.org/r/20241017131434.40935-5-steven.price@arm.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Cai Xinchen <caixinchen1@huawei.com> --- arch/arm64/include/asm/io.h | 8 ++++++++ arch/arm64/include/asm/rsi.h | 2 ++ arch/arm64/include/asm/rsi_cmds.h | 21 +++++++++++++++++++++ arch/arm64/kernel/rsi.c | 26 ++++++++++++++++++++++++++ 4 files changed, 57 insertions(+) diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index 9f92f92ad62d..8f3bbf168ec7 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -17,6 +17,7 @@ #include <asm/early_ioremap.h> #include <asm/alternative.h> #include <asm/cpufeature.h> +#include <asm/rsi.h> /* * Generic IO read/write. These perform native-endian accesses. @@ -186,4 +187,11 @@ extern bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size, unsigned long flags); #define arch_memremap_can_ram_remap arch_memremap_can_ram_remap +static inline bool arm64_is_protected_mmio(phys_addr_t phys_addr, size_t size) +{ + if (unlikely(is_realm_world())) + return __arm64_is_protected_mmio(phys_addr, size); + return false; +} + #endif /* __ASM_IO_H */ diff --git a/arch/arm64/include/asm/rsi.h b/arch/arm64/include/asm/rsi.h index acba065eb00e..188cbb9b23f5 100644 --- a/arch/arm64/include/asm/rsi.h +++ b/arch/arm64/include/asm/rsi.h @@ -14,6 +14,8 @@ DECLARE_STATIC_KEY_FALSE(rsi_present); void __init arm64_rsi_init(void); +bool __arm64_is_protected_mmio(phys_addr_t base, size_t size); + static inline bool is_realm_world(void) { return static_branch_unlikely(&rsi_present); diff --git a/arch/arm64/include/asm/rsi_cmds.h b/arch/arm64/include/asm/rsi_cmds.h index 2fcf351b5634..e6a211001bd3 100644 --- a/arch/arm64/include/asm/rsi_cmds.h +++ b/arch/arm64/include/asm/rsi_cmds.h @@ -45,6 +45,27 @@ static inline unsigned long rsi_get_realm_config(struct realm_config *cfg) return res.a0; } +static inline unsigned long rsi_ipa_state_get(phys_addr_t start, + phys_addr_t end, + enum ripas *state, + phys_addr_t *top) +{ + struct arm_smccc_res res; + + arm_smccc_smc(SMC_RSI_IPA_STATE_GET, + start, end, 0, 0, 0, 0, 0, + &res); + + if (res.a0 == RSI_SUCCESS) { + if (top) + *top = res.a1; + if (state) + *state = res.a2; + } + + return res.a0; +} + static inline long rsi_set_addr_range_state(phys_addr_t start, phys_addr_t end, enum ripas state, diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c index cea8f0d39591..7e7934c4fca0 100644 --- a/arch/arm64/kernel/rsi.c +++ b/arch/arm64/kernel/rsi.c @@ -67,6 +67,32 @@ static void __init arm64_rsi_setup_memory(void) } } +bool __arm64_is_protected_mmio(phys_addr_t base, size_t size) +{ + enum ripas ripas; + phys_addr_t end, top; + + /* Overflow ? */ + if (WARN_ON(base + size <= base)) + return false; + + end = ALIGN(base + size, RSI_GRANULE_SIZE); + base = ALIGN_DOWN(base, RSI_GRANULE_SIZE); + + while (base < end) { + if (WARN_ON(rsi_ipa_state_get(base, end, &ripas, &top))) + break; + if (WARN_ON(top <= base)) + break; + if (ripas != RSI_RIPAS_DEV) + break; + base = top; + } + + return base >= end; +} +EXPORT_SYMBOL(__arm64_is_protected_mmio); + void __init arm64_rsi_init(void) { if (arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_SMC) -- 2.18.0.huawei.25