| Message ID | 20221110134505.1375955-3-sudeep.holla@arm.com (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Headers | show |
| Series | ACPI: Implement FFH OpRegion support | expand |
On Thu, Nov 10, 2022 at 01:45:05PM +0000, Sudeep Holla wrote: > FFH Operation Region space can be used to trigger SMC or HVC calls, > using the Arm SMC Calling Convention (SMCCC). The choice of conduit > (SMC or HVC) is based on what the kernel choose based on PSCI as with > any other users of SMCCC within the kernel. > > Function identifiers only in the SMCCC SiP Service, OEM Service and FF-A > specific call range are allowed in FFH Opregions. > > Offset can be either 0(32 bit calling convention) or 1(64 bit calling > convention). The length must be set with the range applicable based > on the value of the offset. > > Acked-by: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > --- > Hi Will, > > Catalin had acked the changes to be routed via PM tree for last or the > one previous merge window. Since we were waiting for ACPICA changes, it > was not merged. Now that ACPICA changes are queued(via PM tree), I will > ask Rafael to take these patches now. Just thought I will let you know > since you are handling upcoming merge window and I do see few ACPI related > changes there. I don't see any conflict with this, so it should be fine. > > Please let me know if you are fine with that and ack is an add-on :). I'm happy either way, so I'll leave this for Rafael but just poke me if you want me to queue them instead. Will
On Mon, Nov 14, 2022 at 7:05 PM Will Deacon <will@kernel.org> wrote: > > On Thu, Nov 10, 2022 at 01:45:05PM +0000, Sudeep Holla wrote: > > FFH Operation Region space can be used to trigger SMC or HVC calls, > > using the Arm SMC Calling Convention (SMCCC). The choice of conduit > > (SMC or HVC) is based on what the kernel choose based on PSCI as with > > any other users of SMCCC within the kernel. > > > > Function identifiers only in the SMCCC SiP Service, OEM Service and FF-A > > specific call range are allowed in FFH Opregions. > > > > Offset can be either 0(32 bit calling convention) or 1(64 bit calling > > convention). The length must be set with the range applicable based > > on the value of the offset. > > > > Acked-by: Catalin Marinas <catalin.marinas@arm.com> > > Cc: Will Deacon <will@kernel.org> > > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> > > --- > > Hi Will, > > > > Catalin had acked the changes to be routed via PM tree for last or the > > one previous merge window. Since we were waiting for ACPICA changes, it > > was not merged. Now that ACPICA changes are queued(via PM tree), I will > > ask Rafael to take these patches now. Just thought I will let you know > > since you are handling upcoming merge window and I do see few ACPI related > > changes there. I don't see any conflict with this, so it should be fine. > > > > Please let me know if you are fine with that and ack is an add-on :). > > I'm happy either way, so I'll leave this for Rafael but just poke me if you > want me to queue them instead. Both patches in the series applied as 6.2 material, thank you!
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index a5a256e3f9fe..378453faa87e 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -13,6 +13,7 @@ #define pr_fmt(fmt) "ACPI: " fmt #include <linux/acpi.h> +#include <linux/arm-smccc.h> #include <linux/cpumask.h> #include <linux/efi.h> #include <linux/efi-bgrt.h> @@ -411,3 +412,108 @@ void arch_reserve_mem_area(acpi_physical_address addr, size_t size) { memblock_mark_nomap(addr, size); } + +#ifdef CONFIG_ACPI_FFH +/* + * Implements ARM64 specific callbacks to support ACPI FFH Operation Region as + * specified in https://developer.arm.com/docs/den0048/latest + */ +struct acpi_ffh_data { + struct acpi_ffh_info info; + void (*invoke_ffh_fn)(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 *args, + struct arm_smccc_quirk *res); + void (*invoke_ffh64_fn)(const struct arm_smccc_1_2_regs *args, + struct arm_smccc_1_2_regs *res); +}; + +int acpi_ffh_address_space_arch_setup(void *handler_ctxt, void **region_ctxt) +{ + enum arm_smccc_conduit conduit; + struct acpi_ffh_data *ffh_ctxt; + + ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL); + if (!ffh_ctxt) + return -ENOMEM; + + if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) + return -EOPNOTSUPP; + + conduit = arm_smccc_1_1_get_conduit(); + if (conduit == SMCCC_CONDUIT_NONE) { + pr_err("%s: invalid SMCCC conduit\n", __func__); + return -EOPNOTSUPP; + } + + if (conduit == SMCCC_CONDUIT_SMC) { + ffh_ctxt->invoke_ffh_fn = __arm_smccc_smc; + ffh_ctxt->invoke_ffh64_fn = arm_smccc_1_2_smc; + } else { + ffh_ctxt->invoke_ffh_fn = __arm_smccc_hvc; + ffh_ctxt->invoke_ffh64_fn = arm_smccc_1_2_hvc; + } + + memcpy(ffh_ctxt, handler_ctxt, sizeof(ffh_ctxt->info)); + + *region_ctxt = ffh_ctxt; + return AE_OK; +} + +static bool acpi_ffh_smccc_owner_allowed(u32 fid) +{ + int owner = ARM_SMCCC_OWNER_NUM(fid); + + if (owner == ARM_SMCCC_OWNER_STANDARD || + owner == ARM_SMCCC_OWNER_SIP || owner == ARM_SMCCC_OWNER_OEM) + return true; + + return false; +} + +int acpi_ffh_address_space_arch_handler(acpi_integer *value, void *region_context) +{ + int ret = 0; + struct acpi_ffh_data *ffh_ctxt = region_context; + + if (ffh_ctxt->info.offset == 0) { + /* SMC/HVC 32bit call */ + struct arm_smccc_res res; + u32 a[8] = { 0 }, *ptr = (u32 *)value; + + if (!ARM_SMCCC_IS_FAST_CALL(*ptr) || ARM_SMCCC_IS_64(*ptr) || + !acpi_ffh_smccc_owner_allowed(*ptr) || + ffh_ctxt->info.length > 32) { + ret = AE_ERROR; + } else { + int idx, len = ffh_ctxt->info.length >> 2; + + for (idx = 0; idx < len; idx++) + a[idx] = *(ptr + idx); + + ffh_ctxt->invoke_ffh_fn(a[0], a[1], a[2], a[3], a[4], + a[5], a[6], a[7], &res, NULL); + memcpy(value, &res, sizeof(res)); + } + + } else if (ffh_ctxt->info.offset == 1) { + /* SMC/HVC 64bit call */ + struct arm_smccc_1_2_regs *r = (struct arm_smccc_1_2_regs *)value; + + if (!ARM_SMCCC_IS_FAST_CALL(r->a0) || !ARM_SMCCC_IS_64(r->a0) || + !acpi_ffh_smccc_owner_allowed(r->a0) || + ffh_ctxt->info.length > sizeof(*r)) { + ret = AE_ERROR; + } else { + ffh_ctxt->invoke_ffh64_fn(r, r); + memcpy(value, r, ffh_ctxt->info.length); + } + } else { + ret = AE_ERROR; + } + + return ret; +} +#endif /* CONFIG_ACPI_FFH */