x86/platform/UV: Add obtaining GAM Range Table from UV BIOS

UV4 uses a GAM (globally addressed memory) architecture that supports
variable sized memory per node.  This replaces the old "M" value (number
of address bits per node) with a range table for conversions between
addresses and physical node (pnode) id's.  This table is obtained from UV
BIOS via the EFI UVsystab table.  Support for older EFI UVsystab tables
is maintained.

Tested-by: Dimitri Sivanich <sivanich@sgi.com>
Tested-by: John Estabrook <estabrook@sgi.com>
Tested-by: Gary Kroening <gfk@sgi.com>
Tested-by: Nathan Zimmer <nzimmer@sgi.com>
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Andrew Banman <abanman@sgi.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russ Anderson <rja@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160429215405.329827545@asylum.americas.sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 23 insertions, 25 deletions

diff --git a/arch/x86/platform/uv/bios_uv.c b/arch/x86/platform/uv/bios_uv.c
index 1584cbed0dce..815fec6e05e2 100644
--- a/arch/x86/platform/uv/bios_uv.c
+++ b/arch/x86/platform/uv/bios_uv.c
@@ -21,19 +21,20 @@
 
 #include <linux/efi.h>
 #include <linux/export.h>
+#include <linux/slab.h>
 #include <asm/efi.h>
 #include <linux/io.h>
 #include <asm/uv/bios.h>
 #include <asm/uv/uv_hub.h>
 
-static struct uv_systab uv_systab;
+struct uv_systab *uv_systab;
 
 s64 uv_bios_call(enum uv_bios_cmd which, u64 a1, u64 a2, u64 a3, u64 a4, u64 a5)
 {
-	struct uv_systab *tab = &uv_systab;
+	struct uv_systab *tab = uv_systab;
 	s64 ret;
 
-	if (!tab->function)
+	if (!tab || !tab->function)
 		/*
 		 * BIOS does not support UV systab
 		 */
@@ -183,34 +184,31 @@ int uv_bios_set_legacy_vga_target(bool decode, int domain, int bus)
 }
 EXPORT_SYMBOL_GPL(uv_bios_set_legacy_vga_target);
 
-
 #ifdef CONFIG_EFI
 void uv_bios_init(void)
 {
-	struct uv_systab *tab;
-
-	if ((efi.uv_systab == EFI_INVALID_TABLE_ADDR) ||
-	    (efi.uv_systab == (unsigned long)NULL)) {
-		printk(KERN_CRIT "No EFI UV System Table.\n");
-		uv_systab.function = (unsigned long)NULL;
+	uv_systab = NULL;
+	if ((efi.uv_systab == EFI_INVALID_TABLE_ADDR) || !efi.uv_systab) {
+		pr_crit("UV: UVsystab: missing\n");
 		return;
 	}
 
-	tab = (struct uv_systab *)ioremap(efi.uv_systab,
-					sizeof(struct uv_systab));
-	if (strncmp(tab->signature, "UVST", 4) != 0)
-		printk(KERN_ERR "bad signature in UV system table!");
-
-	/*
-	 * Copy table to permanent spot for later use.
-	 */
-	memcpy(&uv_systab, tab, sizeof(struct uv_systab));
-	iounmap(tab);
+	uv_systab = ioremap(efi.uv_systab, 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);
+		return;
+	}
 
-	printk(KERN_INFO "EFI UV System Table Revision %d\n",
-					uv_systab.revision);
+	if (uv_systab->revision >= UV_SYSTAB_VERSION_UV4) {
+		iounmap(uv_systab);
+		uv_systab = ioremap(efi.uv_systab, uv_systab->size);
+		if (!uv_systab) {
+			pr_err("UV: UVsystab: ioremap(%d) failed!\n",
+				uv_systab->size);
+			return;
+		}
+	}
+	pr_info("UV: UVsystab: Revision:%x\n", uv_systab->revision);
 }
-#else	/* !CONFIG_EFI */
-
-void uv_bios_init(void) { }
 #endif