[SeaBIOS] [PATCHv3] support T13 EDD3.0 spec

[Sebastian Herbszt]

Gleb Natapov wrote:
> On Mon, Jan 10, 2011 at 09:15:19PM +0100, Sebastian Herbszt wrote:
>> Gleb Natapov wrote:
>> >Some guests (such as Linux) expect BIOS to behave according to T13
>> 
>> "Some software expects BIOS ..." instead? "Guests" sounds misleading since
>> this feature can also be expected by userland software.
>> 
>> >EDD3.0 spec. T13 spec is much better then Phoenix since it provides
>> >more information about interface and device paths. This patch adds
>> 
>> "T13 spec provides more information about interface and device paths."
>> 
>> >support for the spec. If guest provides buffer with enough space for
>> 
>> "If caller provides ...".
>> 
> Yeah, I have to admit my head is full of vitalization ;)
> 
>> >T13 EDD info return EDD according to T13 spec otherwise use Phoenix
>> >one.
>> >
>> >Signed-off-by: Gleb Natapov <gleb at redhat.com>
>> >diff --git a/src/disk.c b/src/disk.c
>> >index f7bfe9c..8f7c61f 100644
>> >--- a/src/disk.c
>> >+++ b/src/disk.c
>> >@@ -503,6 +503,7 @@ static void
>> >disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >{
>> >    u16 size = GET_INT13DPT(regs, size);
>> >+    u16 t13 = size == 74;
>> >
>> >    // Buffer is too small
>> >    if (size < 26) {
>> >@@ -553,8 +554,9 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >    // EDD 2.x
>> >
>> >    int bdf;
>> >-    u16 iobase1;
>> >-    u64 device_path;
>> >+    u16 iobase1 = 0;
>> >+    u64 device_path = 0;
>> >+    u8 channel = 0;
>> >    SET_INT13DPT(regs, size, 30);
>> >    if (type == DTYPE_ATA || type == DTYPE_ATAPI) {
>> >        u16 ebda_seg = get_ebda_seg();
>> >@@ -573,6 +575,7 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >        iobase1 = GET_GLOBALFLAT(chan_gf->iobase1);
>> >        bdf = GET_GLOBALFLAT(chan_gf->pci_bdf);
>> >        device_path = slave;
>> >+        channel = GET_GLOBALFLAT(chan_gf->chanid);
>> >
>> >        u16 options = 0;
>> >        if (type == DTYPE_ATA) {
>> >@@ -613,8 +616,6 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >        SET_INT13DPT(regs, dpte_segment, 0);
>> >        SET_INT13DPT(regs, dpte_offset, 0);
>> >        bdf = GET_GLOBAL(drive_g->cntl_id);
>> >-        device_path = 0;
>> >-        iobase1 = 0;
>> >    }
>> >
>> >    if (size < 66) {
>> >@@ -624,7 +625,7 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >
>> >    // EDD 3.x
>> >    SET_INT13DPT(regs, key, 0xbedd);
>> >-    SET_INT13DPT(regs, dpi_length, 36);
>> >+    SET_INT13DPT(regs, dpi_length, t13 ? 44 : 36);
>> >    SET_INT13DPT(regs, reserved1, 0);
>> >    SET_INT13DPT(regs, reserved2, 0);
>> >
>> >@@ -632,17 +633,20 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >        SET_INT13DPT(regs, host_bus[0], 'P');
>> >        SET_INT13DPT(regs, host_bus[1], 'C');
>> >        SET_INT13DPT(regs, host_bus[2], 'I');
>> >-        SET_INT13DPT(regs, host_bus[3], 0);
>> >+        SET_INT13DPT(regs, host_bus[3], ' ');
>> >
>> >        u32 path = (pci_bdf_to_bus(bdf) | (pci_bdf_to_dev(bdf) << 8)
>> >                    | (pci_bdf_to_fn(bdf) << 16));
>> >+        if (t13)
>> >+            path |= channel << 24;
>> >+
>> >        SET_INT13DPT(regs, iface_path, path);
>> >    } else {
>> >        // ISA
>> >        SET_INT13DPT(regs, host_bus[0], 'I');
>> >        SET_INT13DPT(regs, host_bus[1], 'S');
>> >        SET_INT13DPT(regs, host_bus[2], 'A');
>> >-        SET_INT13DPT(regs, host_bus[3], 0);
>> >+        SET_INT13DPT(regs, host_bus[3], ' ');
>> >
>> >        SET_INT13DPT(regs, iface_path, iobase1);
>> >    }
>> >@@ -651,22 +655,30 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
>> >        SET_INT13DPT(regs, iface_type[0], 'A');
>> >        SET_INT13DPT(regs, iface_type[1], 'T');
>> >        SET_INT13DPT(regs, iface_type[2], 'A');
>> >-        SET_INT13DPT(regs, iface_type[3], 0);
>> >+        SET_INT13DPT(regs, iface_type[3], ' ');
>> >    } else {
>> >        SET_INT13DPT(regs, iface_type[0], 'S');
>> >        SET_INT13DPT(regs, iface_type[1], 'C');
>> >        SET_INT13DPT(regs, iface_type[2], 'S');
>> >        SET_INT13DPT(regs, iface_type[3], 'I');
>> >    }
>> >-    SET_INT13DPT(regs, iface_type[4], 0);
>> >-    SET_INT13DPT(regs, iface_type[5], 0);
>> >-    SET_INT13DPT(regs, iface_type[6], 0);
>> >-    SET_INT13DPT(regs, iface_type[7], 0);
>> >+    SET_INT13DPT(regs, iface_type[4], ' ');
>> >+    SET_INT13DPT(regs, iface_type[5], ' ');
>> >+    SET_INT13DPT(regs, iface_type[6], ' ');
>> >+    SET_INT13DPT(regs, iface_type[7], ' ');
>> >+
>> >+    if (t13) {
>> >+        SET_INT13DPT(regs, t13.device_path[0], device_path);
>> >+        SET_INT13DPT(regs, t13.device_path[1], 0);
>> >
>> >-    SET_INT13DPT(regs, device_path, device_path);
>> >+        SET_INT13DPT(regs, t13.checksum
>> >+                     , -checksum_far(regs->ds, (void*)(regs->si+30), 43));
>> >+    } else {
>> >+        SET_INT13DPT(regs, phoenix.device_path, device_path);
>> >
>> >-    SET_INT13DPT(regs, checksum
>> >-                 , -checksum_far(regs->ds, (void*)(regs->si+30), 35));
>> >+        SET_INT13DPT(regs, phoenix.checksum
>> >+                     , -checksum_far(regs->ds, (void*)(regs->si+30), 35));
>> >+    }
>> 
>> Should the 0 to space padding part be a separate commit? Some pre-T13 spec
>> BIOS do space padding too.
>> 
> Unless we are planing to port space padding fix to stable branch I do
> not see the need in separate commit.

That change is not directly linked to the T13 EDD 3.0 spec and a separate commit
would point that out. Also bisect would blame the correct change.

Sebastian