On Fri, Oct 23, 2020 at 10:04 AM Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx> wrote: > > Initial support for S2Idle based on the Intel implementation[1] does not > work for AMD as the BIOS implementation for ACPI methods like the _DSM > are not standardized. > > So, the way in which the UUID's were parsed and the ACPI packages were > retrieved out of the ACPI objects are not the same between Intel and AMD. > > This patch adds AMD support for S2Idle to parse the UUID, evaluate the > _DSM methods, preparing the Idle constaint list etc. constraint > Link: https://uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf # [1] > Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx> > --- > drivers/acpi/sleep.c | 166 ++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 158 insertions(+), 8 deletions(-) > > diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c > index aff13bf4d947..a36b4ddcd1e9 100644 > --- a/drivers/acpi/sleep.c > +++ b/drivers/acpi/sleep.c > @@ -710,6 +710,11 @@ static const struct acpi_device_id lps0_device_ids[] = { > #define ACPI_LPS0_ENTRY 5 > #define ACPI_LPS0_EXIT 6 > > +/* AMD */ > +#define ACPI_LPS0_DSM_UUID_AMD "e3f32452-febc-43ce-9039-932122d37721" > +#define ACPI_LPS0_SCREEN_OFF_AMD 4 > +#define ACPI_LPS0_SCREEN_ON_AMD 5 > + > static acpi_handle lps0_device_handle; > static guid_t lps0_dsm_guid; > static char lps0_dsm_func_mask; > @@ -733,8 +738,128 @@ struct lpi_constraints { > int min_dstate; > }; > > +/* AMD */ > +/* Device constraint entry structure */ > +struct lpi_device_info_amd { > + int revision; > + int count; > + union acpi_object *package; > +}; > + > +/* Constraint package structure */ > +struct lpi_device_constraint_amd { > + char *name; > + int enabled; > + int function_states; > + int min_dstate; > +}; > + > static struct lpi_constraints *lpi_constraints_table; > static int lpi_constraints_table_size; > +static int rev_id; > + > +static void lpi_device_get_constraints_amd(void) > +{ > + union acpi_object *out_obj; > + int i, j, k; > + > + out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid, > + 1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS, > + NULL, ACPI_TYPE_PACKAGE); > + > + if (!out_obj) > + return; > + > + acpi_handle_info(lps0_device_handle, "_DSM function 1 eval %s\n", > + out_obj ? "successful" : "failed"); The existing lpi_device_get_constraints() uses acpi_handle_debug(). Why is it necessary to use acpi_handle_info() here? > + > + for (i = 0; i < out_obj->package.count; i++) { > + union acpi_object *package = &out_obj->package.elements[i]; > + struct lpi_device_info_amd info = { }; > + > + if (package->type == ACPI_TYPE_INTEGER) { > + switch (i) { > + case 0: > + info.revision = package->integer.value; > + break; > + case 1: > + info.count = package->integer.value; > + break; > + default: > + break; Not needed AFAICS. > + } > + } else if (package->type == ACPI_TYPE_PACKAGE) { > + lpi_constraints_table = kcalloc(package->package.count, > + sizeof(*lpi_constraints_table), > + GFP_KERNEL); > + > + if (!lpi_constraints_table) > + goto free_acpi_buffer; > + > + acpi_handle_info(lps0_device_handle, > + "LPI: constraints list begin:\n"); > + > + for (j = 0; j < package->package.count; ++j) { > + union acpi_object *info_obj = &package->package.elements[j]; > + struct lpi_device_constraint_amd dev_info = {}; > + struct lpi_constraints *list; > + acpi_status status; > + > + for (k = 0; k < info_obj->package.count; ++k) { > + union acpi_object *obj = &info_obj->package.elements[k]; > + union acpi_object *obj_new; > + > + list = &lpi_constraints_table[lpi_constraints_table_size]; > + list->min_dstate = -1; > + > + obj_new = &obj[k]; > + switch (k) { > + case 0: > + dev_info.enabled = obj->integer.value; > + break; > + case 1: > + dev_info.name = obj->string.pointer; > + break; > + case 2: > + dev_info.function_states = obj->integer.value; > + break; > + case 3: > + dev_info.min_dstate = obj->integer.value; > + break; > + default: > + break; Likewise. > + } > + > + if (!dev_info.enabled || !dev_info.name || > + !dev_info.min_dstate) > + continue; > + > + status = acpi_get_handle(NULL, dev_info.name, > + &list->handle); > + if (ACPI_FAILURE(status)) > + continue; > + > + acpi_handle_info(lps0_device_handle, > + "index:%d Name:%s\n", k, dev_info.name); > + > + list->min_dstate = dev_info.min_dstate; > + > + if (list->min_dstate < 0) { > + acpi_handle_info(lps0_device_handle, > + "Incomplete constraint defined\n"); > + continue; > + } > + } > + lpi_constraints_table_size++; > + } > + } > + } > + > + acpi_handle_info(lps0_device_handle, "LPI: constraints list end\n"); > + > +free_acpi_buffer: > + ACPI_FREE(out_obj); > +} > > static void lpi_device_get_constraints(void) > { > @@ -883,7 +1008,7 @@ static void acpi_sleep_run_lps0_dsm(unsigned int func) > if (!(lps0_dsm_func_mask & (1 << func))) > return; > > - out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, 1, func, NULL); > + out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL); > ACPI_FREE(out_obj); > > acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n", > @@ -894,6 +1019,7 @@ static int lps0_device_attach(struct acpi_device *adev, > const struct acpi_device_id *not_used) > { > union acpi_object *out_obj; > + struct cpuinfo_x86 *c = &boot_cpu_data; Why do you need this pointer on the stack? What would be wrong with accessing boot_cpu_data directly below? Besides, this file doesn't depend on X86 and it may not build on the other architectures after your changes.
