linux/drivers/acpi/arm64/ffh.c
Sudeep Holla 7a7a1cac3c arm64: FFH: Move ACPI specific code into drivers/acpi/arm64/
The ACPI FFH Opregion code can be moved out of arm64 arch code as
it just uses SMCCC. Move all the ACPI FFH Opregion code into
drivers/acpi/arm64/ffh.c

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://lore.kernel.org/r/20240605131458.3341095-4-sudeep.holla@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2024-06-13 10:18:40 +01:00

108 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/acpi.h>
#include <linux/arm-smccc.h>
#include <linux/slab.h>
/*
* 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;
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;
}
ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL);
if (!ffh_ctxt)
return -ENOMEM;
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;
}