efifb: Support overriding fields FW tells us with the DMI data.

Some machines apparently give us bogus linelength/stride/pitch data, so
we need to support letting the DMI table override the supplied data.

I bet you can't guess whose machines I'm talking about.

Signed-off-by: Peter Jones <pjones@redhat.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/drivers/video/efifb.c b/drivers/video/efifb.c
index a9645b8..2359b64 100644 (file)
--- a/drivers/video/efifb.c
+++ b/drivers/video/efifb.c
@@ -68,41 +68,48 @@ enum {
        M_UNKNOWN       /* placeholder */
 };
 
+#define OVERRIDE_NONE  0x0
+#define OVERRIDE_BASE  0x1
+#define OVERRIDE_STRIDE        0x2
+#define OVERRIDE_HEIGHT        0x4
+#define OVERRIDE_WIDTH 0x8
+
 static struct efifb_dmi_info {
        char *optname;
        unsigned long base;
        int stride;
        int width;
        int height;
+       int flags;
 } dmi_list[] __initdata = {
-       [M_I17] = { "i17", 0x80010000, 1472 * 4, 1440, 900 },
-       [M_I20] = { "i20", 0x80010000, 1728 * 4, 1680, 1050 }, /* guess */
-       [M_I20_SR] = { "imac7", 0x40010000, 1728 * 4, 1680, 1050 },
-       [M_I24] = { "i24", 0x80010000, 2048 * 4, 1920, 1200 }, /* guess */
-       [M_I24_8_1] = { "imac8", 0xc0060000, 2048 * 4, 1920, 1200 },
-       [M_I24_10_1] = { "imac10", 0xc0010000, 2048 * 4, 1920, 1080 },
-       [M_I27_11_1] = { "imac11", 0xc0010000, 2560 * 4, 2560, 1440 },
-       [M_MINI]= { "mini", 0x80000000, 2048 * 4, 1024, 768 },
-       [M_MINI_3_1] = { "mini31", 0x40010000, 1024 * 4, 1024, 768 },
-       [M_MINI_4_1] = { "mini41", 0xc0010000, 2048 * 4, 1920, 1200 },
-       [M_MB] = { "macbook", 0x80000000, 2048 * 4, 1280, 800 },
-       [M_MB_5_1] = { "macbook51", 0x80010000, 2048 * 4, 1280, 800 },
-       [M_MB_6_1] = { "macbook61", 0x80010000, 2048 * 4, 1280, 800 },
-       [M_MB_7_1] = { "macbook71", 0x80010000, 2048 * 4, 1280, 800 },
-       [M_MBA] = { "mba", 0x80000000, 2048 * 4, 1280, 800 },
-       [M_MBP] = { "mbp", 0x80010000, 1472 * 4, 1440, 900 },
-       [M_MBP_2] = { "mbp2", 0, 0, 0, 0 }, /* placeholder */
-       [M_MBP_2_2] = { "mbp22", 0x80010000, 1472 * 4, 1440, 900 },
-       [M_MBP_SR] = { "mbp3", 0x80030000, 2048 * 4, 1440, 900 },
-       [M_MBP_4] = { "mbp4", 0xc0060000, 2048 * 4, 1920, 1200 },
-       [M_MBP_5_1] = { "mbp51", 0xc0010000, 2048 * 4, 1440, 900 },
-       [M_MBP_5_2] = { "mbp52", 0xc0010000, 2048 * 4, 1920, 1200 },
-       [M_MBP_5_3] = { "mbp53", 0xd0010000, 2048 * 4, 1440, 900 },
-       [M_MBP_6_1] = { "mbp61", 0x90030000, 2048 * 4, 1920, 1200 },
-       [M_MBP_6_2] = { "mbp62", 0x90030000, 2048 * 4, 1680, 1050 },
-       [M_MBP_7_1] = { "mbp71", 0xc0010000, 2048 * 4, 1280, 800 },
-       [M_MBP_8_2] = { "mbp82", 0x90010000, 1472 * 4, 1440, 900 },
-       [M_UNKNOWN] = { NULL, 0, 0, 0, 0 }
+       [M_I17] = { "i17", 0x80010000, 1472 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_I20] = { "i20", 0x80010000, 1728 * 4, 1680, 1050, OVERRIDE_NONE }, /* guess */
+       [M_I20_SR] = { "imac7", 0x40010000, 1728 * 4, 1680, 1050, OVERRIDE_NONE },
+       [M_I24] = { "i24", 0x80010000, 2048 * 4, 1920, 1200, OVERRIDE_NONE }, /* guess */
+       [M_I24_8_1] = { "imac8", 0xc0060000, 2048 * 4, 1920, 1200, OVERRIDE_NONE },
+       [M_I24_10_1] = { "imac10", 0xc0010000, 2048 * 4, 1920, 1080, OVERRIDE_NONE },
+       [M_I27_11_1] = { "imac11", 0xc0010000, 2560 * 4, 2560, 1440, OVERRIDE_NONE },
+       [M_MINI]= { "mini", 0x80000000, 2048 * 4, 1024, 768, OVERRIDE_NONE },
+       [M_MINI_3_1] = { "mini31", 0x40010000, 1024 * 4, 1024, 768, OVERRIDE_NONE },
+       [M_MINI_4_1] = { "mini41", 0xc0010000, 2048 * 4, 1920, 1200, OVERRIDE_NONE },
+       [M_MB] = { "macbook", 0x80000000, 2048 * 4, 1280, 800, OVERRIDE_NONE },
+       [M_MB_5_1] = { "macbook51", 0x80010000, 2048 * 4, 1280, 800, OVERRIDE_NONE },
+       [M_MB_6_1] = { "macbook61", 0x80010000, 2048 * 4, 1280, 800, OVERRIDE_NONE },
+       [M_MB_7_1] = { "macbook71", 0x80010000, 2048 * 4, 1280, 800, OVERRIDE_NONE },
+       [M_MBA] = { "mba", 0x80000000, 2048 * 4, 1280, 800, OVERRIDE_NONE },
+       [M_MBP] = { "mbp", 0x80010000, 1472 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_MBP_2] = { "mbp2", 0, 0, 0, 0, OVERRIDE_NONE }, /* placeholder */
+       [M_MBP_2_2] = { "mbp22", 0x80010000, 1472 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_MBP_SR] = { "mbp3", 0x80030000, 2048 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_MBP_4] = { "mbp4", 0xc0060000, 2048 * 4, 1920, 1200, OVERRIDE_NONE },
+       [M_MBP_5_1] = { "mbp51", 0xc0010000, 2048 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_MBP_5_2] = { "mbp52", 0xc0010000, 2048 * 4, 1920, 1200, OVERRIDE_NONE },
+       [M_MBP_5_3] = { "mbp53", 0xd0010000, 2048 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_MBP_6_1] = { "mbp61", 0x90030000, 2048 * 4, 1920, 1200, OVERRIDE_NONE },
+       [M_MBP_6_2] = { "mbp62", 0x90030000, 2048 * 4, 1680, 1050, OVERRIDE_NONE },
+       [M_MBP_7_1] = { "mbp71", 0xc0010000, 2048 * 4, 1280, 800, OVERRIDE_NONE },
+       [M_MBP_8_2] = { "mbp82", 0x90010000, 1472 * 4, 1440, 900, OVERRIDE_NONE },
+       [M_UNKNOWN] = { NULL, 0, 0, 0, 0, OVERRIDE_NONE }
 };
 
 static int set_system(const struct dmi_system_id *id);
@@ -157,16 +164,22 @@ static const struct dmi_system_id dmi_system_table[] __initconst = {
        {},
 };
 
+#define choose_value(dmivalue, fwvalue, field, flags) ({       \
+               typeof(fwvalue) _ret_ = fwvalue;                \
+               if ((flags) & (field))                          \
+                       _ret_ = dmivalue;                       \
+               else if ((fwvalue) == 0)                        \
+                       _ret_ = dmivalue;                       \
+               _ret_;                                          \
+       })
+
 static int set_system(const struct dmi_system_id *id)
 {
        struct efifb_dmi_info *info = id->driver_data;
-       if (info->base == 0)
-               return 0;
 
-       printk(KERN_INFO "efifb: dmi detected %s - framebuffer at %p "
-                        "(%dx%d, stride %d)\n", id->ident,
-                        (void *)info->base, info->width, info->height,
-                        info->stride);
+       if (info->base == 0 && info->height == 0 && info->width == 0
+                       && info->stride == 0)
+               return 0;
 
        /* Trust the bootloader over the DMI tables */
        if (screen_info.lfb_base == 0) {
@@ -174,40 +187,47 @@ static int set_system(const struct dmi_system_id *id)
                struct pci_dev *dev = NULL;
                int found_bar = 0;
 #endif
-               screen_info.lfb_base = info->base;
+               if (info->base) {
+                       screen_info.lfb_base = choose_value(info->base,
+                               screen_info.lfb_base, OVERRIDE_BASE,
+                               info->flags);
 
 #if defined(CONFIG_PCI)
-               /* make sure that the address in the table is actually on a
-                * VGA device's PCI BAR */
-
-               for_each_pci_dev(dev) {
-                       int i;
-                       if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
-                               continue;
-                       for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
-                               resource_size_t start, end;
-
-                               start = pci_resource_start(dev, i);
-                               if (start == 0)
-                                       break;
-                               end = pci_resource_end(dev, i);
-                               if (screen_info.lfb_base >= start &&
-                                               screen_info.lfb_base < end) {
-                                       found_bar = 1;
+                       /* make sure that the address in the table is actually
+                        * on a VGA device's PCI BAR */
+
+                       for_each_pci_dev(dev) {
+                               int i;
+                               if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
+                                       continue;
+                               for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
+                                       resource_size_t start, end;
+
+                                       start = pci_resource_start(dev, i);
+                                       if (start == 0)
+                                               break;
+                                       end = pci_resource_end(dev, i);
+                                       if (screen_info.lfb_base >= start &&
+                                           screen_info.lfb_base < end) {
+                                               found_bar = 1;
+                                       }
                                }
                        }
-               }
-               if (!found_bar)
-                       screen_info.lfb_base = 0;
+                       if (!found_bar)
+                               screen_info.lfb_base = 0;
 #endif
+               }
        }
        if (screen_info.lfb_base) {
-               if (screen_info.lfb_linelength == 0)
-                       screen_info.lfb_linelength = info->stride;
-               if (screen_info.lfb_width == 0)
-                       screen_info.lfb_width = info->width;
-               if (screen_info.lfb_height == 0)
-                       screen_info.lfb_height = info->height;
+               screen_info.lfb_linelength = choose_value(info->stride,
+                       screen_info.lfb_linelength, OVERRIDE_STRIDE,
+                       info->flags);
+               screen_info.lfb_width = choose_value(info->width,
+                       screen_info.lfb_width, OVERRIDE_WIDTH,
+                       info->flags);
+               screen_info.lfb_height = choose_value(info->height,
+                       screen_info.lfb_height, OVERRIDE_HEIGHT,
+                       info->flags);
                if (screen_info.orig_video_isVGA == 0)
                        screen_info.orig_video_isVGA = VIDEO_TYPE_EFI;
        } else {
@@ -217,6 +237,13 @@ static int set_system(const struct dmi_system_id *id)
                screen_info.orig_video_isVGA = 0;
                return 0;
        }
+
+       printk(KERN_INFO "efifb: dmi detected %s - framebuffer at %p "
+                        "(%dx%d, stride %d)\n", id->ident,
+                        (void *)screen_info.lfb_base, screen_info.lfb_width,
+                        screen_info.lfb_height, screen_info.lfb_linelength);
+
+
        return 1;
 }