[mubios] Add EDD parameters and normalize PS/2 input

5 files changed, 129 insertions, 4 deletions

diff --git a/mubios/arch/irq.S b/mubios/arch/irq.S
index 0c192ff..99eb9b3 100644
--- a/mubios/arch/irq.S
+++ b/mubios/arch/irq.S
@@ -25,6 +25,7 @@
 	.equ BDA_BASE, 0x0400
 	.equ BDA_KBD_BUFFER_START, 0x001E
 	.equ BDA_KBD_BUFFER_END, 0x003E
+	.equ BDA_KBD_BREAK_PREFIX, 0x0497
 
 	.equ TIMER_TICKS_PER_DAY_LOW, 0x00B0
 	.equ TIMER_TICKS_PER_DAY_HIGH, 0x0018
@@ -83,12 +84,25 @@ irq1_entry:
 	in al, 0x60
 	mov dl, al
 
-	test dl, 0x80
-	jnz irq1_send_eoi
-
 	xor ax, ax
 	mov ds, ax
 
+	# Ignore a PS/2 set-2 break prefix and its following release code.
+	cmp dl, 0xF0
+	jne irq1_check_break_prefix
+	mov byte ptr [BDA_KBD_BREAK_PREFIX], 1
+	jmp irq1_send_eoi
+
+irq1_check_break_prefix:
+	cmp byte ptr [BDA_KBD_BREAK_PREFIX], 0
+	je irq1_check_set1_break
+	mov byte ptr [BDA_KBD_BREAK_PREFIX], 0
+	jmp irq1_send_eoi
+
+irq1_check_set1_break:
+	test dl, 0x80
+	jnz irq1_send_eoi
+
 	mov bx, word ptr [0x041C]
 	mov ax, bx
 	add ax, 2
diff --git a/mubios/drivers/ata.c b/mubios/drivers/ata.c
index 928a7d1..a7c6d8d 100644
--- a/mubios/drivers/ata.c
+++ b/mubios/drivers/ata.c
@@ -36,6 +36,7 @@
 #define ATA_STATUS_BSY 0x80u
 
 #define ATA_CMD_READ_SECTORS 0x20u
+#define ATA_CMD_IDENTIFY 0xECu
 
 static u8
 ata_wait_not_busy (void)
@@ -111,3 +112,42 @@ ata_read_sectors28 (u32 lba, u16 *buffer, u16 count)
 
   return 0;
 }
+
+u8
+ata_identify (u16 *cylinders, u16 *heads, u16 *sectors_per_track,
+              u32 *total_sectors_low, u32 *total_sectors_high)
+{
+  u16 identify_data[256];
+  u8 status;
+  u16 index;
+
+  status = ata_wait_not_busy ();
+  if ((status & ATA_STATUS_ERR) != 0)
+    return 1;
+
+  io_out8 (ATA_DRIVE, 0xE0u);
+  ata_delay_400ns ();
+
+  io_out8 (ATA_SECTOR_COUNT, 0);
+  io_out8 (ATA_LBA_LOW, 0);
+  io_out8 (ATA_LBA_MID, 0);
+  io_out8 (ATA_LBA_HIGH, 0);
+  io_out8 (ATA_COMMAND, ATA_CMD_IDENTIFY);
+
+  status = ata_wait_not_busy ();
+  if ((status & ATA_STATUS_ERR) != 0 || (status & ATA_STATUS_DRQ) == 0)
+    return 1;
+
+  for (index = 0; index < 256; ++index)
+    identify_data[index] = io_in16 (ATA_DATA);
+
+  *cylinders = identify_data[1];
+  *heads = identify_data[3];
+  *sectors_per_track = identify_data[6];
+  *total_sectors_low
+      = (u32)identify_data[60] | ((u32)identify_data[61] << 16);
+  *total_sectors_high
+      = (u32)identify_data[100] | ((u32)identify_data[101] << 16);
+
+  return 0;
+}
diff --git a/mubios/include/bios.h b/mubios/include/bios.h
index 456d212..7ec2198 100644
--- a/mubios/include/bios.h
+++ b/mubios/include/bios.h
@@ -51,6 +51,8 @@ void ioapic_init (void);
 void ivt_init (void);
 
 u8 ata_read_sectors28 (u32 lba, u16 *buffer, u16 count);
+u8 ata_identify (u16 *cylinders, u16 *heads, u16 *sectors_per_track,
+                 u32 *total_sectors_low, u32 *total_sectors_high);
 
 struct bios_regs;
 
diff --git a/mubios/services/int13.c b/mubios/services/int13.c
index 2c12261..73d553b 100644
--- a/mubios/services/int13.c
+++ b/mubios/services/int13.c
@@ -35,6 +35,19 @@ struct edd_packet
   u32 lba_high;
 } __attribute__ ((packed));
 
+struct edd_parameters
+{
+  u16 size;
+  u16 flags;
+  u32 cylinders_low;
+  u32 cylinders_high;
+  u32 heads;
+  u32 sectors_per_track;
+  u32 total_sectors_low;
+  u32 total_sectors_high;
+  u16 bytes_per_sector;
+} __attribute__ ((packed));
+
 static void
 int13_fail (struct bios_regs *regs)
 {
@@ -51,6 +64,15 @@ get_edd_packet (struct bios_regs *regs)
   return (struct edd_packet *)address;
 }
 
+static struct edd_parameters *
+get_edd_parameters (struct bios_regs *regs)
+{
+  u32 address;
+
+  address = ((u32)regs->ds << 4) + (u16)regs->esi;
+  return (struct edd_parameters *)address;
+}
+
 void
 int13_service (struct bios_regs *regs)
 {
@@ -103,5 +125,40 @@ int13_service (struct bios_regs *regs)
       return;
     }
 
+  if (function == 0x48u)
+    {
+      struct edd_parameters *parameters;
+      u16 cylinders;
+      u16 heads;
+      u16 sectors_per_track;
+      u32 total_sectors_low;
+      u32 total_sectors_high;
+
+      parameters = get_edd_parameters (regs);
+
+      if (parameters->size < 0x001Eu
+          || ata_identify (&cylinders, &heads, &sectors_per_track,
+                           &total_sectors_low, &total_sectors_high)
+                 != 0)
+        {
+          int13_fail (regs);
+          return;
+        }
+
+      parameters->size = 0x001Eu;
+      parameters->flags = 0;
+      parameters->cylinders_low = cylinders;
+      parameters->cylinders_high = 0;
+      parameters->heads = heads;
+      parameters->sectors_per_track = sectors_per_track;
+      parameters->total_sectors_low = total_sectors_low;
+      parameters->total_sectors_high = total_sectors_high;
+      parameters->bytes_per_sector = 512;
+
+      regs->eax = 0;
+      regs->flags &= (u16)~BIOS_CF;
+      return;
+    }
+
   int13_fail (regs);
 }
diff --git a/mubios/services/int16.c b/mubios/services/int16.c
index 4a04828..5872fb1 100644
--- a/mubios/services/int16.c
+++ b/mubios/services/int16.c
@@ -27,6 +27,18 @@
 #define BDA_KBD_BUFFER_END 0x003Eu
 
 static u8
+normalize_scancode (u8 scancode)
+{
+  switch (scancode)
+    {
+    case 0x5Au:
+      return 0x1Cu;
+    default:
+      return scancode;
+    }
+}
+
+static u8
 scancode_to_ascii (u8 scancode)
 {
   switch (scancode)
@@ -126,7 +138,7 @@ int16_service (struct bios_regs *regs)
 
   position = *head;
   value = buffer[(position - BDA_KBD_BUFFER_START) >> 1];
-  scancode = (u8)(value >> 8);
+  scancode = normalize_scancode ((u8)(value >> 8));
   ascii = scancode_to_ascii (scancode);
 
   regs->eax = ((u32)scancode << 8) | ascii;