write-multiple support

Is flush-ata-cache even needed? Reading the ATA 5 spec more closely, it
looks like it's only required by ATAPI devices! (Packet Interface is what
the 'PI' stands for!) And it's unclear if my driver actually supports ATAPI
at the moment.

1 files changed, 24 insertions, 3 deletions

diff --git a/boot.subx b/boot.subx
index 0b840d58..b2ac17b6 100644
--- a/boot.subx
+++ b/boot.subx
@@ -347,7 +347,7 @@ keyboard-interrupt-handler:
   # check output buffer of 8042 keyboard controller (https://web.archive.org/web/20040604041507/http://panda.cs.ndsu.nodak.edu/~achapwes/PICmicro/keyboard/atkeyboard.html)
   e4/read-port-into-al 0x64/imm8
   a8/test-bits-in-al 0x01/imm8  # set zf if bit 0 (least significant) is not set
-  74/jump-if-not-set $keyboard-interrupt-handler:epilogue/disp8
+  0f 84/jump-if-not-set $keyboard-interrupt-handler:epilogue/disp32
   # - if keyboard buffer is full, return
   # var dest-addr/ecx: (addr byte) = (keyboard-buffer + *keyboard-buffer:write)
   31/xor %ecx 1/r32/ecx
@@ -357,7 +357,7 @@ keyboard-interrupt-handler:
   8a/byte-> *ecx 0/r32/al
   # if (al != 0) return
   3c/compare-al-and 0/imm8
-  75/jump-if-!= $keyboard-interrupt-handler:epilogue/disp8
+  0f 85/jump-if-!= $keyboard-interrupt-handler:epilogue/disp32
   # - read keycode
   e4/read-port-into-al 0x60/imm8
   # - key released
@@ -950,6 +950,7 @@ load-sectors:  # disk: (addr disk), lba: int, n: int, out: (addr stream byte)
       49/decrement-ecx
       eb/jump loop/disp8
     }
+    # next sector
     ff 1/subop/decrement *(ebp+0x10)
 #?     (draw-int32-decimal-wrapping-right-then-down-from-cursor-over-full-screen 0 *(ebp+0x10) 0xc 0)
     81 7/subop/compare *(ebp+0x10) 0/imm32
@@ -988,6 +989,8 @@ store-sectors:  # disk: (addr disk), lba: int, n: int, in: (addr stream byte)
   (ata-lba *(ebp+8) *(ebp+0xc))
   (ata-command *(ebp+8) 0x30)  # write sectors with retries
   # for each sector
+#?   (set-cursor-position 0 0 0)
+#?   (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "0" 7 0)
   {
     # wait
     (while-ata-busy *(ebp+8))
@@ -1000,6 +1003,7 @@ store-sectors:  # disk: (addr disk), lba: int, n: int, in: (addr stream byte)
     # . var first-byte/ebx: byte
     # . when it's more than 0xff, we're at an even-numbered byte
     bb/copy-to-ebx 0xffff/imm32
+#?     (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "D" 7 0)
 $store-sectors:store-sector:
     {
       81 7/subop/compare %ecx 0/imm32
@@ -1028,6 +1032,7 @@ $store-sectors:store-sector:
       eb/jump loop/disp8
     }
     # write out final first-byte if necessary
+#?     (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "I" 7 0)
     81 7/subop/compare %ebx 0xff/imm32
     {
       7f/jump-if-> break/disp8
@@ -1037,6 +1042,7 @@ $store-sectors:store-sector:
       49/decrement-ecx
     }
     # pad zeroes
+#?     (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "P" 7 0)
     31/xor %eax 0/r32/eax
     {
       81 7/subop/compare %ecx 0/imm32
@@ -1046,8 +1052,19 @@ $store-sectors:store-sector:
       49/decrement-ecx
       eb/jump loop/disp8
     }
+    # next sector
+#?     (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "N" 7 0)
+    ff 1/subop/decrement *(ebp+0x10)
+    81 7/subop/compare *(ebp+0x10) 0/imm32
+    7e/jump-if-<= break/disp8
+#?     (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "W" 7 0)
+    (wait-400ns *(ebp+8))
+#?     (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "L" 7 0)
+    e9/jump loop/disp32
   }
+#?   (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "F" 7 0)
   (flush-ata-cache *(ebp+8))
+#?   (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "Y" 7 0)
 $store-sectors:end:
   # . restore registers
   5b/pop-to-ebx
@@ -1335,8 +1352,12 @@ flush-ata-cache:  # disk: (addr disk)
   #
   (ata-drive-select *(ebp+8) 0)
   (ata-command *(ebp+8) 0xe7)  # flush cache
+#?   (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "W" 7 0)
   (while-ata-busy *(ebp+8))
-  (until-ata-ready-for-data *(ebp+8))
+#?   (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "X" 7 0)
+  # TODO: seems unneeded? works for a single sector but Qemu hangs with multiple
+  # sectors. Data is still written.
+#?   (until-ata-ready-for-data *(ebp+8))
 $flush-ata-cache:end:
   # . epilogue
   89/<- %esp 5/r32/ebp