Merge branch 'acpi-scan' into acpi-cleanup

[firefly-linux-kernel-4.4.55.git] / arch / x86 / kernel / setup.c

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 23ddd558fbd52d1376576b200122448d94165708..00f6c1472b850472e5f9759dd5ad9613f6c026be 100644 (file)
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -610,6 +610,83 @@ static __init void reserve_ibft_region(void)
 
 static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
 
+static bool __init snb_gfx_workaround_needed(void)
+{
+#ifdef CONFIG_PCI
+       int i;
+       u16 vendor, devid;
+       static const __initconst u16 snb_ids[] = {
+               0x0102,
+               0x0112,
+               0x0122,
+               0x0106,
+               0x0116,
+               0x0126,
+               0x010a,
+       };
+
+       /* Assume no if something weird is going on with PCI */
+       if (!early_pci_allowed())
+               return false;
+
+       vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
+       if (vendor != 0x8086)
+               return false;
+
+       devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
+       for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
+               if (devid == snb_ids[i])
+                       return true;
+#endif
+
+       return false;
+}
+
+/*
+ * Sandy Bridge graphics has trouble with certain ranges, exclude
+ * them from allocation.
+ */
+static void __init trim_snb_memory(void)
+{
+       static const __initconst unsigned long bad_pages[] = {
+               0x20050000,
+               0x20110000,
+               0x20130000,
+               0x20138000,
+               0x40004000,
+       };
+       int i;
+
+       if (!snb_gfx_workaround_needed())
+               return;
+
+       printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
+
+       /*
+        * Reserve all memory below the 1 MB mark that has not
+        * already been reserved.
+        */
+       memblock_reserve(0, 1<<20);
+       
+       for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
+               if (memblock_reserve(bad_pages[i], PAGE_SIZE))
+                       printk(KERN_WARNING "failed to reserve 0x%08lx\n",
+                              bad_pages[i]);
+       }
+}
+
+/*
+ * Here we put platform-specific memory range workarounds, i.e.
+ * memory known to be corrupt or otherwise in need to be reserved on
+ * specific platforms.
+ *
+ * If this gets used more widely it could use a real dispatch mechanism.
+ */
+static void __init trim_platform_memory_ranges(void)
+{
+       trim_snb_memory();
+}
+
 static void __init trim_bios_range(void)
 {
        /*
@@ -630,6 +707,7 @@ static void __init trim_bios_range(void)
         * take them out.
         */
        e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
+
        sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 }
 
@@ -908,6 +986,8 @@ void __init setup_arch(char **cmdline_p)
 
        setup_real_mode();
 
+       trim_platform_memory_ranges();
+
        init_gbpages();
 
        /* max_pfn_mapped is updated here */