efi/x86: move UV_SYSTAB handling into arch/x86

The SGI UV UEFI machines are tightly coupled to the x86 architecture
so there is no need to keep any awareness of its existence in the
generic EFI layer, especially since we already have the infrastructure
to handle arch-specific configuration tables, and were even already
using it to some extent.
Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>

arch/x86/include/asm/uv/uv.h

@@ -12,10 +12,12 @@ struct mm_struct;
 #ifdef CONFIG_X86_UV
 #include <linux/efi.h>
 
+extern unsigned long uv_systab_phys;
+
 extern enum uv_system_type get_uv_system_type(void);
 static inline bool is_early_uv_system(void)
 {
-	return !((efi.uv_systab == EFI_INVALID_TABLE_ADDR) || !efi.uv_systab);
+	return uv_systab_phys && uv_systab_phys != EFI_INVALID_TABLE_ADDR;
 }
 extern int is_uv_system(void);
 extern int is_uv_hubless(void);

arch/x86/platform/efi/efi.c

@@ -59,7 +59,7 @@ static efi_system_table_t efi_systab __initdata;
 
 static efi_config_table_type_t arch_tables[] __initdata = {
 #ifdef CONFIG_X86_UV
-	{UV_SYSTEM_TABLE_GUID, "UVsystab", &efi.uv_systab},
+	{UV_SYSTEM_TABLE_GUID, "UVsystab", &uv_systab_phys},
 #endif
 	{NULL_GUID, NULL, NULL},
 };
@@ -74,7 +74,9 @@ static const unsigned long * const efi_tables[] = {
 	&efi.boot_info,
 	&efi.hcdp,
 	&efi.uga,
-	&efi.uv_systab,
+#ifdef CONFIG_X86_UV
+	&uv_systab_phys,
+#endif
 	&efi.fw_vendor,
 	&efi.runtime,
 	&efi.config_table,

arch/x86/platform/uv/bios_uv.c

@@ -14,6 +14,8 @@
 #include <asm/uv/bios.h>
 #include <asm/uv/uv_hub.h>
 
+unsigned long uv_systab_phys __ro_after_init = EFI_INVALID_TABLE_ADDR;
+
 struct uv_systab *uv_systab;
 
 static s64 __uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3,
@@ -185,13 +187,13 @@ EXPORT_SYMBOL_GPL(uv_bios_set_legacy_vga_target);
 void uv_bios_init(void)
 {
 	uv_systab = NULL;
-	if ((efi.uv_systab == EFI_INVALID_TABLE_ADDR) ||
-	    !efi.uv_systab || efi_runtime_disabled()) {
+	if ((uv_systab_phys == EFI_INVALID_TABLE_ADDR) ||
+	    !uv_systab_phys || efi_runtime_disabled()) {
 		pr_crit("UV: UVsystab: missing\n");
 		return;
 	}
 
-	uv_systab = ioremap(efi.uv_systab, sizeof(struct uv_systab));
+	uv_systab = ioremap(uv_systab_phys, sizeof(struct uv_systab));
 	if (!uv_systab || strncmp(uv_systab->signature, UV_SYSTAB_SIG, 4)) {
 		pr_err("UV: UVsystab: bad signature!\n");
 		iounmap(uv_systab);
@@ -203,7 +205,7 @@ void uv_bios_init(void)
 		int size = uv_systab->size;
 
 		iounmap(uv_systab);
-		uv_systab = ioremap(efi.uv_systab, size);
+		uv_systab = ioremap(uv_systab_phys, size);
 		if (!uv_systab) {
 			pr_err("UV: UVsystab: ioremap(%d) failed!\n", size);
 			return;

drivers/firmware/efi/efi.c

@@ -43,7 +43,6 @@ struct efi __read_mostly efi = {
 	.boot_info		= EFI_INVALID_TABLE_ADDR,
 	.hcdp			= EFI_INVALID_TABLE_ADDR,
 	.uga			= EFI_INVALID_TABLE_ADDR,
-	.uv_systab		= EFI_INVALID_TABLE_ADDR,
 	.fw_vendor		= EFI_INVALID_TABLE_ADDR,
 	.runtime		= EFI_INVALID_TABLE_ADDR,
 	.config_table		= EFI_INVALID_TABLE_ADDR,

include/linux/efi.h

@@ -988,7 +988,6 @@ extern struct efi {
 	unsigned long boot_info;	/* boot info table */
 	unsigned long hcdp;		/* HCDP table */
 	unsigned long uga;		/* UGA table */
-	unsigned long uv_systab;	/* UV system table */
 	unsigned long fw_vendor;	/* fw_vendor */
 	unsigned long runtime;		/* runtime table */
 	unsigned long config_table;	/* config tables */