On Wed, May 18, 2022 at 11:09 AM Pierre Gondois <pierre.gondois@xxxxxxx> wrote:
>
> ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities':
> Starting with ACPI Specification 6.2, all _CPC registers can be in
> PCC, System Memory, System IO, or Functional Fixed Hardware address
> spaces. OSPM support for this more flexible register space scheme is
> indicated by the “Flexible Address Space for CPPC Registers” _OSC bit
>
> Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in:
> - PCC or Functional Fixed Hardware address space if defined
> - SystemMemory address space (NULL register) if not defined
>
> Add the corresponding _OSC bit and check it when parsing _CPC objects.
>
> Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
> Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> ---
> drivers/acpi/bus.c | 18 ++++++++++++++++++
> drivers/acpi/cppc_acpi.c | 9 +++++++++
> include/linux/acpi.h | 2 ++
> 3 files changed, 29 insertions(+)
>
> diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c
> index 3e58b613a2c4..9eca43d1d941 100644
> --- a/drivers/acpi/bus.c
> +++ b/drivers/acpi/bus.c
> @@ -278,6 +278,20 @@ bool osc_sb_apei_support_acked;
> bool osc_pc_lpi_support_confirmed;
> EXPORT_SYMBOL_GPL(osc_pc_lpi_support_confirmed);
>
> +/*
> + * ACPI 6.2 Section 6.2.11.2 'Platform-Wide OSPM Capabilities':
> + * Starting with ACPI Specification 6.2, all _CPC registers can be in
> + * PCC, System Memory, System IO, or Functional Fixed Hardware address
> + * spaces. OSPM support for this more flexible register space scheme is
> + * indicated by the “Flexible Address Space for CPPC Registers” _OSC bit.
> + *
> + * Otherwise (cf ACPI 6.1, s8.4.7.1.1.X), _CPC registers must be in:
> + * - PCC or Functional Fixed Hardware address space if defined
> + * - SystemMemory address space (NULL register) if not defined
> + */
> +bool osc_cpc_flexible_adr_space_confirmed;
> +EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed);
> +
> /*
> * ACPI 6.4 Operating System Capabilities for USB.
> */
> @@ -321,6 +335,8 @@ static void acpi_bus_osc_negotiate_platform_control(void)
> }
> #endif
>
> + capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
> +
> if (IS_ENABLED(CONFIG_SCHED_MC_PRIO))
> capbuf[OSC_SUPPORT_DWORD] |= OSC_SB_CPC_DIVERSE_HIGH_SUPPORT;
>
> @@ -366,6 +382,8 @@ static void acpi_bus_osc_negotiate_platform_control(void)
> capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_PCLPI_SUPPORT;
> osc_sb_native_usb4_support_confirmed =
> capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT;
> + osc_cpc_flexible_adr_space_confirmed =
> + capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE;
> }
>
> kfree(context.ret.pointer);
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index bc1454789a06..6f09fe011544 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -736,6 +736,11 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
> if (gas_t->address) {
> void __iomem *addr;
>
> + if (!osc_cpc_flexible_adr_space_confirmed) {
> + pr_debug("Flexible address space capability not supported\n");
> + goto out_free;
> + }
> +
> addr = ioremap(gas_t->address, gas_t->bit_width/8);
> if (!addr)
> goto out_free;
> @@ -758,6 +763,10 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
> gas_t->address);
> goto out_free;
> }
> + if (!osc_cpc_flexible_adr_space_confirmed) {
> + pr_debug("Flexible address space capability not supported\n");
> + goto out_free;
> + }
> } else {
> if (gas_t->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE || !cpc_ffh_supported()) {
> /* Support only PCC, SystemMemory, SystemIO, and FFH type regs. */
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index d7136d13aa44..03465db16b68 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -574,6 +574,7 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context);
> #define OSC_SB_OSLPI_SUPPORT 0x00000100
> #define OSC_SB_CPC_DIVERSE_HIGH_SUPPORT 0x00001000
> #define OSC_SB_GENERIC_INITIATOR_SUPPORT 0x00002000
> +#define OSC_SB_CPC_FLEXIBLE_ADR_SPACE 0x00004000
> #define OSC_SB_NATIVE_USB4_SUPPORT 0x00040000
> #define OSC_SB_PRM_SUPPORT 0x00200000
>
> @@ -581,6 +582,7 @@ extern bool osc_sb_apei_support_acked;
> extern bool osc_pc_lpi_support_confirmed;
> extern bool osc_sb_native_usb4_support_confirmed;
> extern bool osc_sb_cppc_not_supported;
> +extern bool osc_cpc_flexible_adr_space_confirmed;
>
> /* USB4 Capabilities */
> #define OSC_USB_USB3_TUNNELING 0x00000001
> --
Applied as 5.19 material along with the rest of the series, thanks!
