apei, mce: Factor out APEI architecture specific MCE calls.

This commit abstracts MCE calls and provides weak corresponding default
implementation for those architectures which do not need arch specific
actions. Each platform willing to do additional architectural actions
should provides desired function definition. It allows us to avoid wrap
code into #ifdef in generic code and prevent new platform from introducing
dummy stub function too.

Initially, there are two APEI arch-specific calls:
- arch_apei_enable_cmcff()
- arch_apei_report_mem_error()
Both interact with MCE driver for X86 architecture.

Signed-off-by: Tomasz Nowicki <[e-mail]>
Acked-by: Borislav Petkov <[e-mail]>
Signed-off-by: Tony Luck <[e-mail]>

arch/x86/kernel/acpi/Makefile

···
 obj-$(CONFIG_ACPI)		+= boot.o
 obj-$(CONFIG_ACPI_SLEEP)	+= sleep.o wakeup_$(BITS).o
+obj-$(CONFIG_ACPI_APEI)		+= apei.o
 
 ifneq ($(CONFIG_ACPI_PROCESSOR),)
 obj-y				+= cstate.o

arch/x86/kernel/acpi/apei.c

···
+/*
+ * Arch-specific APEI-related functions.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <acpi/apei.h>
+
+#include <asm/mce.h>
+
+int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data)
+{
+#ifdef CONFIG_X86_MCE
+	int i;
+	struct acpi_hest_ia_corrected *cmc;
+	struct acpi_hest_ia_error_bank *mc_bank;
+
+	if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
+		return 0;
+
+	cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
+	if (!cmc->enabled)
+		return 0;
+
+	/*
+	 * We expect HEST to provide a list of MC banks that report errors
+	 * in firmware first mode. Otherwise, return non-zero value to
+	 * indicate that we are done parsing HEST.
+	 */
+	if (!(cmc->flags & ACPI_HEST_FIRMWARE_FIRST) ||
+	    !cmc->num_hardware_banks)
+		return 1;
+
+	pr_info("HEST: Enabling Firmware First mode for corrected errors.\n");
+
+	mc_bank = (struct acpi_hest_ia_error_bank *)(cmc + 1);
+	for (i = 0; i < cmc->num_hardware_banks; i++, mc_bank++)
+		mce_disable_bank(mc_bank->bank_number);
+#endif
+	return 1;
+}
+
+void arch_apei_report_mem_error(int sev, struct cper_sec_mem_err *mem_err)
+{
+#ifdef CONFIG_X86_MCE
+	apei_mce_report_mem_error(sev, mem_err);
+#endif
+}

drivers/acpi/apei/apei-base.c

···
 }
 EXPORT_SYMBOL_GPL(apei_get_debugfs_dir);
 
+int __weak arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr,
+				  void *data)
+{
+	return 1;
+}
+EXPORT_SYMBOL_GPL(arch_apei_enable_cmcff);
+
+void __weak arch_apei_report_mem_error(int sev,
+				       struct cper_sec_mem_err *mem_err)
+{
+}
+EXPORT_SYMBOL_GPL(arch_apei_report_mem_error);
+
 int apei_osc_setup(void)
 {
 	static u8 whea_uuid_str[] = "ed855e0c-6c90-47bf-a62a-26de0fc5ad5c";

drivers/acpi/apei/ghes.c

···
 #include <linux/aer.h>
 
 #include <acpi/ghes.h>
-#include <asm/mce.h>
+#include <acpi/apei.h>
 #include <asm/tlbflush.h>
 #include <asm/nmi.h>
 
···
 			mem_err = (struct cper_sec_mem_err *)(gdata+1);
 			ghes_edac_report_mem_error(ghes, sev, mem_err);
 
-#ifdef CONFIG_X86_MCE
-			apei_mce_report_mem_error(sev, mem_err);
-#endif
+			arch_apei_report_mem_error(sev, mem_err);
 			ghes_handle_memory_failure(gdata, sev);
 		}
 #ifdef CONFIG_ACPI_APEI_PCIEAER

drivers/acpi/apei/hest.c

···
 #include <linux/io.h>
 #include <linux/platform_device.h>
 #include <acpi/apei.h>
-#include <asm/mce.h>
 
 #include "apei-internal.h"
 
···
  */
 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
 {
-#ifdef CONFIG_X86_MCE
-	int i;
-	struct acpi_hest_ia_corrected *cmc;
-	struct acpi_hest_ia_error_bank *mc_bank;
-
-	if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
-		return 0;
-
-	cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
-	if (!cmc->enabled)
-		return 0;
-
-	/*
-	 * We expect HEST to provide a list of MC banks that report errors
-	 * in firmware first mode. Otherwise, return non-zero value to
-	 * indicate that we are done parsing HEST.
-	 */
-	if (!(cmc->flags & ACPI_HEST_FIRMWARE_FIRST) || !cmc->num_hardware_banks)
-		return 1;
-
-	pr_info(HEST_PFX "Enabling Firmware First mode for corrected errors.\n");
-
-	mc_bank = (struct acpi_hest_ia_error_bank *)(cmc + 1);
-	for (i = 0; i < cmc->num_hardware_banks; i++, mc_bank++)
-		mce_disable_bank(mc_bank->bank_number);
-#endif
-	return 1;
+	return arch_apei_enable_cmcff(hest_hdr, data);
 }
 
 struct ghes_arr {

include/acpi/apei.h

···
 		  size_t buflen);
 int erst_clear(u64 record_id);
 
+int arch_apei_enable_cmcff(struct acpi_hest_header *hest_hdr, void *data);
+void arch_apei_report_mem_error(int sev, struct cper_sec_mem_err *mem_err);
+
 #endif
 #endif