src/mainboard/lenovo/t420/early_init.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <device/pci_ops.h>
   4 #include <drivers/lenovo/hybrid_graphics/hybrid_graphics.h>
   5 #include <northbridge/intel/sandybridge/sandybridge.h>
   6
   7 static void hybrid_graphics_init(void)
   8 {
   9         bool peg, igd;
  10         u32 reg32;
  11
  12         early_hybrid_graphics(&igd, &peg);
  13
  14         if (peg && igd)
  15                 return;
  16
  17         /* Hide disabled devices */
  18         reg32 = pci_read_config32(PCI_DEV(0, 0, 0), DEVEN);
  19         reg32 &= ~(DEVEN_PEG10 | DEVEN_IGD);
  20
  21         if (peg)
  22                 reg32 |= DEVEN_PEG10;
  23
  24         if (igd)
  25                 reg32 |= DEVEN_IGD;
  26         else
  27                 /* Disable IGD VGA decode, no GTT or GFX stolen */
  28                 pci_write_config16(PCI_DEV(0, 0, 0), GGC, 2);
  29
  30         pci_write_config32(PCI_DEV(0, 0, 0), DEVEN, reg32);
  31 }
  32
  33 void mainboard_early_init(int s3resume)
  34 {
  35         hybrid_graphics_init();
  36 }