src/soc/intel/baytrail/int15.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <arch/interrupt.h>
   4 #include <console/console.h>
   5 #include <soc/int15.h>
   6 #include <x86emu/x86emu.h>
   7
   8 static int int15_handler(void)
   9 {
  10         int res = 1;
  11
  12         printk(BIOS_DEBUG, "%s: AX=%04x BX=%04x CX=%04x DX=%04x\n",
  13                __func__, X86_AX, X86_BX, X86_CX, X86_DX);
  14
  15         switch (X86_AX) {
  16         case 0x5f34:
  17                 /*
  18                  * Set Panel Fitting Hook:
  19                  *  bit 2 = Graphics Stretching
  20                  *  bit 1 = Text Stretching
  21                  *  bit 0 = Centering (do not set with bit1 or bit2)
  22                  *  0     = video BIOS default
  23                  */
  24                 X86_AX = 0x005f;
  25                 X86_CX = 0x0001;
  26                 res = 1;
  27                 break;
  28         case 0x5f35:
  29                 /*
  30                  * Boot Display Device Hook:
  31                  *  bit 0 = CRT
  32                  *  bit 1 = TV
  33                  *  bit 2 = EFP (HDMI)
  34                  *  bit 3 = LFP (eDP)*
  35                  *  bit 4 = CRT2
  36                  *  bit 5 = TV2
  37                  *  bit 6 = EFP2
  38                  *  bit 7 = LFP2
  39                  */
  40                 X86_AX = 0x005f;
  41                 X86_CX = 0x0008;
  42                 res = 1;
  43                 break;
  44         case 0x5f51:
  45                 /*
  46                  * Hook to select active LFP configuration:
  47                  *  00h = No LVDS, VBIOS does not enable LVDS
  48                  *  01h = Int-LVDS, LFP driven by integrated LVDS decoder
  49                  *  02h = SVDO-LVDS, LFP driven by SVDO decoder
  50                  *  03h = eDP, LFP Driven by Int-DisplayPort encoder
  51                  */
  52                 X86_AX = 0x005f;
  53                 X86_CX = 0x0003;
  54                 res = 1;
  55                 break;
  56         case 0x5f70:
  57                 switch ((X86_CX >> 8) & 0xff) {
  58                 case 0:
  59                         /* Get Mux */
  60                         X86_AX = 0x005f;
  61                         X86_CX = 0x0000;
  62                         res = 1;
  63                         break;
  64                 case 1:
  65                         /* Set Mux */
  66                         X86_AX = 0x005f;
  67                         X86_CX = 0x0000;
  68                         res = 1;
  69                         break;
  70                 case 2:
  71                         /* Get SG/Non-SG mode */
  72                         X86_AX = 0x005f;
  73                         X86_CX = 0x0000;
  74                         res = 1;
  75                         break;
  76                 default:
  77                         /* Interrupt was not handled */
  78                         printk(BIOS_DEBUG,
  79                                "Unknown INT15 5f70 function: 0x%02x\n",
  80                                 ((X86_CX >> 8) & 0xff));
  81                         break;
  82                 }
  83                 break;
  84
  85         default:
  86                 printk(BIOS_DEBUG, "Unknown INT15 function %04x!\n", X86_AX);
  87                 break;
  88         }
  89         return res;
  90 }
  91
  92 void install_baytrail_vga_int15_handler(void)
  93 {
  94         mainboard_interrupt_handlers(0x15, &int15_handler);
  95 }