[PATCH v7 05/19] acpi/ghes: prepare to change the way HEST offsets are calculated

[Mauro Carvalho Chehab <mchehab+huawei@kernel.org>]

Add a new ags flag to change the way HEST offsets are calculated.
Currently, offsets needed to store ACPI HEST offsets and read ack
are calculated based on a previous knowledge from the logic
which creates the HEST table.

Such logic is not generic, not allowing to easily add more HEST
entries nor replicates what OSPM does.

As the next patches will be adding a more generic logic, add a
new use_hest_addr, set to false, in preparation for such changes.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
---
 hw/acpi/ghes.c           | 39 ++++++++++++++++++++++++---------------
 hw/arm/virt-acpi-build.c | 13 ++++++++++---
 include/hw/acpi/ghes.h   | 12 +++++++++++-
 3 files changed, 45 insertions(+), 19 deletions(-)

diff --git a/hw/acpi/ghes.c b/hw/acpi/ghes.c
index 84b891fd3dcf..9243b5ad4acb 100644
--- a/hw/acpi/ghes.c
+++ b/hw/acpi/ghes.c
@@ -206,7 +206,8 @@ ghes_gen_err_data_uncorrectable_recoverable(GArray *block,
  * Initialize "etc/hardware_errors" and "etc/hardware_errors_addr" fw_cfg blobs.
  * See docs/specs/acpi_hest_ghes.rst for blobs format.
  */
-static void build_ghes_error_table(GArray *hardware_errors, BIOSLinker *linker)
+static void build_ghes_error_table(AcpiGhesState *ags, GArray *hardware_errors,
+                                   BIOSLinker *linker)
 {
     int i, error_status_block_offset;
 
@@ -251,13 +252,15 @@ static void build_ghes_error_table(GArray *hardware_errors, BIOSLinker *linker)
                                        i * ACPI_GHES_MAX_RAW_DATA_LENGTH);
     }
 
-    /*
-     * tell firmware to write hardware_errors GPA into
-     * hardware_errors_addr fw_cfg, once the former has been initialized.
-     */
-    bios_linker_loader_write_pointer(linker, ACPI_HW_ERROR_ADDR_FW_CFG_FILE, 0,
-                                     sizeof(uint64_t),
-                                     ACPI_HW_ERROR_FW_CFG_FILE, 0);
+    if (!ags->use_hest_addr) {
+        /*
+         * Tell firmware to write hardware_errors GPA into
+         * hardware_errors_addr fw_cfg, once the former has been initialized.
+         */
+        bios_linker_loader_write_pointer(linker, ACPI_HW_ERROR_ADDR_FW_CFG_FILE,
+                                         0, sizeof(uint64_t),
+                                         ACPI_HW_ERROR_FW_CFG_FILE, 0);
+    }
 }
 
 /* Build Generic Hardware Error Source version 2 (GHESv2) */
@@ -331,14 +334,15 @@ static void build_ghes_v2(GArray *table_data,
 }
 
 /* Build Hardware Error Source Table */
-void acpi_build_hest(GArray *table_data, GArray *hardware_errors,
+void acpi_build_hest(AcpiGhesState *ags, GArray *table_data,
+                     GArray *hardware_errors,
                      BIOSLinker *linker,
                      const char *oem_id, const char *oem_table_id)
 {
     AcpiTable table = { .sig = "HEST", .rev = 1,
                         .oem_id = oem_id, .oem_table_id = oem_table_id };
 
-    build_ghes_error_table(hardware_errors, linker);
+    build_ghes_error_table(ags, hardware_errors, linker);
 
     acpi_table_begin(&table, table_data);
 
@@ -357,9 +361,11 @@ void acpi_ghes_add_fw_cfg(AcpiGhesState *ags, FWCfgState *s,
     fw_cfg_add_file(s, ACPI_HW_ERROR_FW_CFG_FILE, hardware_error->data,
                     hardware_error->len);
 
-    /* Create a read-write fw_cfg file for Address */
-    fw_cfg_add_file_callback(s, ACPI_HW_ERROR_ADDR_FW_CFG_FILE, NULL, NULL,
-        NULL, &(ags->hw_error_le), sizeof(ags->hw_error_le), false);
+    if (!ags->use_hest_addr) {
+        /* Create a read-write fw_cfg file for Address */
+        fw_cfg_add_file_callback(s, ACPI_HW_ERROR_ADDR_FW_CFG_FILE, NULL, NULL,
+            NULL, &(ags->hw_error_le), sizeof(ags->hw_error_le), false);
+    }
 }
 
 static void get_hw_error_offsets(uint64_t ghes_addr,
@@ -395,8 +401,11 @@ void ghes_record_cper_errors(AcpiGhesState *ags, const void *cper, size_t len,
     }
 
     assert(ACPI_GHES_ERROR_SOURCE_COUNT == 1);
-    get_hw_error_offsets(le64_to_cpu(ags->hw_error_le),
-                         &cper_addr, &read_ack_register_addr);
+
+    if (!ags->use_hest_addr) {
+        get_hw_error_offsets(le64_to_cpu(ags->hw_error_le),
+                             &cper_addr, &read_ack_register_addr);
+    }
 
     cpu_physical_memory_read(read_ack_register_addr,
                              &read_ack_register, sizeof(read_ack_register));
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 3ac8f8e17861..040d875d4e83 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -946,9 +946,16 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables)
     build_dbg2(tables_blob, tables->linker, vms);
 
     if (vms->ras) {
-        acpi_add_table(table_offsets, tables_blob);
-        acpi_build_hest(tables_blob, tables->hardware_errors, tables->linker,
-                        vms->oem_id, vms->oem_table_id);
+        AcpiGedState *acpi_ged_state;
+        AcpiGhesState *ags;
+
+        acpi_ged_state = ACPI_GED(vms->acpi_dev);
+        ags = &acpi_ged_state->ghes_state;
+        if (ags) {
+            acpi_add_table(table_offsets, tables_blob);
+            acpi_build_hest(ags, tables_blob, tables->hardware_errors,
+                            tables->linker, vms->oem_id, vms->oem_table_id);
+        }
     }
 
     if (ms->numa_state->num_nodes > 0) {
diff --git a/include/hw/acpi/ghes.h b/include/hw/acpi/ghes.h
index f96ac3e85ca2..411f592662af 100644
--- a/include/hw/acpi/ghes.h
+++ b/include/hw/acpi/ghes.h
@@ -64,11 +64,21 @@ enum {
     ACPI_GHES_ERROR_SOURCE_COUNT
 };
 
+/*
+ * AcpiGhesState stores GPA values that will be used to fill HEST entries.
+ *
+ * When use_hest_addr is false, the GPA of the etc/hardware_errors firmware
+ * is stored at hw_error_le. This is the default on QEMU 9.x.
+ *
+ * An GPA value equal to zero means that GHES is not present.
+ */
 typedef struct AcpiGhesState {
     uint64_t hw_error_le;
+    bool use_hest_addr;         /* Currently, always false */
 } AcpiGhesState;
 
-void acpi_build_hest(GArray *table_data, GArray *hardware_errors,
+void acpi_build_hest(AcpiGhesState *ags, GArray *table_data,
+                     GArray *hardware_errors,
                      BIOSLinker *linker,
                      const char *oem_id, const char *oem_table_id);
 void acpi_ghes_add_fw_cfg(AcpiGhesState *vms, FWCfgState *s,
-- 
2.48.1