diff --git a/hw/acpi/cxl.c b/hw/acpi/cxl.c index 92b46bc932..9cd7905ea2 100644 --- a/hw/acpi/cxl.c +++ b/hw/acpi/cxl.c @@ -30,6 +30,75 @@ #include "qapi/error.h" #include "qemu/uuid.h" +void build_cxl_dsm_method(Aml *dev) +{ + Aml *method, *ifctx, *ifctx2; + + method = aml_method("_DSM", 4, AML_SERIALIZED); + { + Aml *function, *uuid; + + uuid = aml_arg(0); + function = aml_arg(2); + /* CXL spec v3.0 9.17.3.1 _DSM Function for Retrieving QTG ID */ + ifctx = aml_if(aml_equal( + uuid, aml_touuid("F365F9A6-A7DE-4071-A66A-B40C0B4F8E52"))); + + /* Function 0, standard DSM query function */ + ifctx2 = aml_if(aml_equal(function, aml_int(0))); + { + uint8_t byte_list[1] = { 0x01 }; /* function 1 only */ + + aml_append(ifctx2, + aml_return(aml_buffer(sizeof(byte_list), byte_list))); + } + aml_append(ifctx, ifctx2); + + /* + * Function 1 + * Creating a package with static values. The max supported QTG ID will + * be 1 and recommended QTG IDs are 0 and then 1. + * The values here are statically created to simplify emulation. Values + * from a real BIOS would be determined by the performance of all the + * present CXL memory and then assigned. + */ + ifctx2 = aml_if(aml_equal(function, aml_int(1))); + { + Aml *pak, *pak1; + + /* + * Return: A package containing two elements - a WORD that returns + * the maximum throttling group that the platform supports, and a + * package containing the QTG ID(s) that the platform recommends. + * Package { + * Max Supported QTG ID + * Package {QTG Recommendations} + * } + * + * While the SPEC specified WORD that hints at the value being + * 16bit, the ACPI dump of BIOS DSDT table showed that the values + * are integers with no specific size specification. aml_int() will + * be used for the values. + */ + pak1 = aml_package(2); + /* Set QTG ID of 0 */ + aml_append(pak1, aml_int(0)); + /* Set QTG ID of 1 */ + aml_append(pak1, aml_int(1)); + + pak = aml_package(2); + /* Set Max QTG 1 */ + aml_append(pak, aml_int(1)); + aml_append(pak, pak1); + + aml_append(ifctx2, aml_return(pak)); + } + aml_append(ifctx, ifctx2); + } + aml_append(method, ifctx); + aml_append(dev, method); +} + static void cedt_build_chbs(GArray *table_data, PXBCXLDev *cxl) { PXBDev *pxb = PXB_DEV(cxl); diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c index b0e1f074f1..80db183b78 100644 --- a/hw/i386/acpi-build.c +++ b/hw/i386/acpi-build.c @@ -1417,6 +1417,7 @@ static void build_acpi0017(Aml *table) method = aml_method("_STA", 0, AML_NOTSERIALIZED); aml_append(method, aml_return(aml_int(0x01))); aml_append(dev, method); + build_cxl_dsm_method(dev); aml_append(scope, dev); aml_append(table, scope); diff --git a/include/hw/acpi/cxl.h b/include/hw/acpi/cxl.h index acf4418886..8f22c71530 100644 --- a/include/hw/acpi/cxl.h +++ b/include/hw/acpi/cxl.h @@ -25,5 +25,6 @@ void cxl_build_cedt(GArray *table_offsets, GArray *table_data, BIOSLinker *linker, const char *oem_id, const char *oem_table_id, CXLState *cxl_state); void build_cxl_osc_method(Aml *dev); +void build_cxl_dsm_method(Aml *dev); #endif