December 2021 - SeaBIOS - mail.coreboot.org

Re: INT 14H
by Paul Edwards Sept. 29, 2022

Sept. 29, 2022

Hi Gerd. Thanks for your reply. Sorry for the delay, was swamped with other things. >> Currently I don't know what to recommend, because I >> don't understand the other side of the INT 13H/14H, >> only the OS side. > Well, the other side talks to the hardware, > and needs drivers to do so. See src/hw > Surely one can write a serial driver which connects to a remote place > using some bluetooth protocol instead of talking to a 16550. That'll > be *alot* of work though, you basically have to implement both > bluetooth stack and hardware driver. I expected to assemble, rather than write, such a thing. If not from the Linux source code, then FreeBSD or ReactOS. If for some reason (what would that be?) no-one has abstracted bluetooth to have a clean interface that I could have trivially reused, then I will put aside my bluetooth dreams and switch to a different technology. How about Wifi? Does that exist in a state usable for my purposes? >> Sure. For now, I want PDOS/386 to remain traditional. >> When I have exhausted everything that is possible >> via the BIOS, I will consider adding UEFI support. > If you want your firmware provide drivers to you for modern hardware you > are in a *much* better position with UEFI. Well, on some/many/most modern machines there is absolutely no other choice - the BIOS doesn't exist, even as CSM. > There is a bluetooth > protocol specification for example, although I'm not sure how common it > is to find an actual uefi driver for bluetooth hardware in the firmware. > Talking to ethernet using the firmware-provided uefi driver shouldn't be > much of a problem though b/c network boot is a rather standard feature. Ok, maybe in the medium term I should use a hardware device, forget the name, that turns ethernet into Wifi. So then the problem is reduced to me needing to provide a BOOTX64.EFI that converts INT 14H into UEFI ethernet calls. >> But I'd like to transport all of that software, designed for >> that environment, and change nothing at all, and have >> it work on a new environment that includes Wifi, bluetooth >> and maybe ethernet, and maybe infrared, and maybe >> other things I don't know about, but make sense (at >> some level) to be accessed via INT 14H. > Well. In the server world it is rather common to provide access to the > serial line over the network for system management purposes. > One approach for that is to have a separate management controller (bmc), > and the serial port of the machine is linked to the management > controller instead of a D9 socket. You can then connect to the bmc to > manage the machine, and one of the options available is to get serial > console access. Ok, this would allow me to have a BBS. But not allow me to have a "virtual modem" so that I can dial out. > Another approach is to have a virtual 16550 provided by the firmware. > Accessing the virtual 16550 will trap into SMM mode where the firmware > emulates a serial device and allows to access the serial port remotely > over the network, roughly comparable to how qemu provides an virtual > 16550 to virtual machines. Ok, but in the case of qemu I have the same issue - at the end of the day I want to drive a modem, so with qemu I can get it to talk to a "virtual modem". If the firmware is providing the serial to network conversion, I also need to stick in a virtual modem there. And that's what I was hoping SeaBIOS would allow me to do. > Note that both approaches work at hardware level not int14h level, > because modern operating systems use int14h services in bootloaders > only if at all. My operating system, PDOS/386, may not be considered "modern", even though it is in active development, but I do wish to use INT 14H, as that was the traditional BIOS service provided, and I wish to maintain contact with the original 80386 machines. I expect a modern environment to have the CPU, memory etc required to support this basic interface. BFN. Paul.

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[PATCH] fw/coreboot.c: Use coreboot table to find cbfs
by Arthur Heymans April 22, 2022

April 22, 2022

The "cbfs master header" cbfs file is considered a legacy feature in coreboot and is planned for removal in the master branch. Since 2015 the coreboot tables have exported info about the active cbfs. This change uses the cbfs information in the coreboot tables instead of following the cbfs master header pointer in the bootblock to find cbfs. This change makes it possible to access CBFS fmap regions that don't feature a "cbfs master header", which is the case with Googles VBOOT solution. This breaks compatibility with very old coreboot build (build before fb5d5b16 "2015-07-14, cbtable: describe boot media"). Keeping backward compatibility with the "cbfs master header" would complicate the code. Signed-off-by: Arthur Heymans <arthur(a)aheymans.xyz> diff --git a/src/Kconfig b/src/Kconfig index 3a8ffa1..51ba827 100644 --- a/src/Kconfig +++ b/src/Kconfig @@ -93,15 +93,6 @@ endchoice help Support CBFS files compressed using the lzma decompression algorithm. - config CBFS_LOCATION - depends on COREBOOT_FLASH - hex "CBFS memory end location" - default 0 - help - Memory address of where the CBFS data ends. This should - be zero for normal builds. It may be a non-zero value if - the CBFS filesystem is at a non-standard location (eg, - 0xffe00000 if CBFS ends 2Meg below the end of flash). config MULTIBOOT depends on COREBOOT diff --git a/src/fw/coreboot.c b/src/fw/coreboot.c index 7c0954b..8a35c1d 100644 --- a/src/fw/coreboot.c +++ b/src/fw/coreboot.c @@ -88,6 +88,18 @@ struct cbmem_console { #define CBMC_OVERFLOW (1 << 31) static struct cbmem_console *cbcon = NULL; +#define CB_TAG_BOOT_MEDIA_PARAMS 0x30 + +struct cb_boot_media_params { + u32 tag; + u32 size; + /* offsets are relative to start of boot media */ + u64 fmap_offset; + u64 cbfs_offset; + u64 cbfs_size; + u64 boot_media_size; +}; + static u16 ipchksum(char *buf, int count) { @@ -146,7 +158,12 @@ find_cb_subtable(struct cb_header *cbh, u32 tag) struct cb_header * find_cb_table(void) { - struct cb_header *cbh = find_cb_header(0, 0x1000); + static struct cb_header *cbh; + + if (cbh) + return cbh; + + cbh= find_cb_header(0, 0x1000); if (!cbh) return NULL; struct cb_forward *cbf = find_cb_subtable(cbh, CB_TAG_FORWARD); @@ -317,20 +334,8 @@ ulzma(u8 *dst, u32 maxlen, const u8 *src, u32 srclen) * Coreboot flash format ****************************************************************/ -#define CBFS_HEADER_MAGIC 0x4F524243 -#define CBFS_VERSION1 0x31313131 - -struct cbfs_header { - u32 magic; - u32 version; - u32 romsize; - u32 bootblocksize; - u32 align; - u32 offset; - u32 pad[2]; -} PACKED; - #define CBFS_FILE_MAGIC 0x455649484352414cLL // LARCHIVE +#define CBFS_ALIGNMENT 64 struct cbfs_file { u64 magic; @@ -429,30 +434,50 @@ coreboot_cbfs_init(void) if (!CONFIG_COREBOOT_FLASH) return; - struct cbfs_header *hdr = *(void **)(CONFIG_CBFS_LOCATION - 4); - if ((u32)hdr & 0x03) { - dprintf(1, "Invalid CBFS pointer %p\n", hdr); + dprintf(3, "Attempting to initialize coreboot cbfs\n"); + + struct cb_header *cbh = find_cb_table(); + if (!cbh) { + dprintf(1, "cbfs_init: unable to find cb table\n"); return; } - if (CONFIG_CBFS_LOCATION && (u32)hdr > CONFIG_CBFS_LOCATION) - // Looks like the pointer is relative to CONFIG_CBFS_LOCATION - hdr = (void*)hdr + CONFIG_CBFS_LOCATION; - if (hdr->magic != cpu_to_be32(CBFS_HEADER_MAGIC)) { - dprintf(1, "Unable to find CBFS (ptr=%p; got %x not %x)\n" - , hdr, hdr->magic, cpu_to_be32(CBFS_HEADER_MAGIC)); + + struct cb_boot_media_params *cbbmp = + find_cb_subtable(cbh, CB_TAG_BOOT_MEDIA_PARAMS); + + if (!cbbmp) { + dprintf(1, "cbfs_init: unable to find boot media params\n"); return; } - dprintf(1, "Found CBFS header at %p\n", hdr); - u32 romsize = be32_to_cpu(hdr->romsize); - u32 romstart = CONFIG_CBFS_LOCATION - romsize; - struct cbfs_file *fhdr = (void*)romstart + be32_to_cpu(hdr->offset); + const u32 romsize = cbbmp->boot_media_size; + const u32 cbfs_start = cbbmp->cbfs_offset - romsize; + const u32 cbfs_end = cbfs_start + cbbmp->cbfs_size - 1; + + dprintf(3, "cbfs_init: cbfs_start=0x%08x, cbfs_end=0x%08x\n", cbfs_start, + cbfs_end); + + u32 offset = cbfs_start; + for (;;) { - if ((u32)fhdr - romstart > romsize) - break; - u64 magic = fhdr->magic; - if (magic != CBFS_FILE_MAGIC) + if (offset > cbfs_end || offset < cbfs_start) break; + + struct cbfs_file *fhdr = (void*)offset; + + if (fhdr->magic != CBFS_FILE_MAGIC) { + offset++; + offset = ALIGN(offset, CBFS_ALIGNMENT); + continue; + } + + /* Skip empty space */ + if (strcmp(fhdr->filename, "") == 0) { + offset += ALIGN(be32_to_cpu(fhdr->offset) + be32_to_cpu(fhdr->len) + , CBFS_ALIGNMENT); + continue; + } + struct cbfs_romfile_s *cfile = malloc_tmp(sizeof(*cfile)); if (!cfile) { warn_noalloc(); @@ -473,8 +498,8 @@ coreboot_cbfs_init(void) } romfile_add(&cfile->file); - fhdr = (void*)ALIGN((u32)cfile->data + cfile->rawsize - , be32_to_cpu(hdr->align)); + offset = ALIGN((u32)cfile->data + cfile->rawsize + , CBFS_ALIGNMENT); } process_links_file(); -- 2.30.2

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[PATCH v3 0/4] nvme: Add PRP List support
by Alexander Graf Jan. 18, 2022

Jan. 18, 2022

While looking at VM bootup times, we stumbled over the fact that the NVMe code only does I/O operations of up to 4kb at a given point in time. This is usually ok, but if you have an OS that loads a lot of data on boot in combination to network backed storage, it shows in bootup times. There is no need to restrict ourselves to 4kb though. The INT13 call we receive gives us much larger chunks which we can just map into a native bigger NVMe I/O call if the request buffer is page aligned. This patch implements all logic required to do the above and gives a substantial performance boost on boot. v1 -> v2: - fix dprintf - Fix bounds check on PRP list add logic - Reduce PRP list to 15 entries embedded in the ns struct. This reduces BIOS reserved memory footprint by 4kb. v2 -> v3: - new patch: nvme: Split requests by maximum allowed size - Adjust the maximum request size to sector units. The hardware field describes it in pages. Alexander Graf (4): nvme: Record maximum allowed request size nvme: Allow to set PRP2 nvme: Pass large I/O requests as PRP lists nvme: Split requests by maximum allowed size src/hw/nvme-int.h | 16 ++++++- src/hw/nvme.c | 122 +++++++++++++++++++++++++++++++++++++++++++++++------- 2 files changed, 121 insertions(+), 17 deletions(-) -- 2.16.4 Amazon Development Center Germany GmbH Krausenstr. 38 10117 Berlin Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B Sitz: Berlin Ust-ID: DE 289 237 879

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new november release?
by Gerd Hoffmann Jan. 14, 2022

Jan. 14, 2022

Hi, It's been a while since the last release, we have some nice but unreleased bits in the master branch (tpm and nvme improvements for example), time for a new release I think. How about freeze in a week, release by roughly mid-november? take care, Gerd

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[PATCH 1/2] readserial: Improve Python3 compatibility
by Kevin O'Connor Dec. 27, 2021

Dec. 27, 2021

Signed-off-by: Kevin O'Connor <kevin(a)koconnor.net> --- scripts/readserial.py | 28 +++++++++++----------------- 1 file changed, 11 insertions(+), 17 deletions(-) diff --git a/scripts/readserial.py b/scripts/readserial.py index a7383e8..e3f56e5 100755 --- a/scripts/readserial.py +++ b/scripts/readserial.py @@ -10,8 +10,6 @@ import sys, os, time, select, optparse -from python23compat import as_bytes - # Reset time counter after this much idle time. RESTARTINTERVAL = 60 # Number of bits in a transmitted byte - 8N1 is 1 start bit + 8 data @@ -20,11 +18,11 @@ BITSPERBYTE = 10 def calibrateserialwrite(outfile, byteadjust): # Build 4000 bytes of dummy data. - data = "0123456789" * 4 + "012345678" + "\n" + data = b"0123456789" * 4 + b"012345678" + b"\n" data = data * 80 while 1: st = time.time() - outfile.write(as_bytes(data)) + outfile.write(data) outfile.flush() et = time.time() sys.stdout.write( @@ -84,38 +82,34 @@ def readserial(infile, logfile, byteadjust): msg = "\n\n======= %s (adjust=%.1fus)\n" % ( time.asctime(time.localtime(datatime)), byteadjust * 1000000) sys.stdout.write(msg) - logfile.write(as_bytes(msg)) + logfile.write(msg.encode()) lasttime = datatime # Translate unprintable chars; add timestamps - out = as_bytes("") - for c in d: + out = bytearray() + for oc in bytearray(d): if isnewline: delta = datatime - starttime - (charcount * byteadjust) - out += "%06.3f: " % delta + out += b"%06.3f: " % delta isnewline = 0 - oc = ord(c) charcount += 1 datatime += byteadjust if oc == 0x0d: continue if oc == 0x00: - out += "<00>\n" + out += b"<00>\n" isnewline = 1 continue if oc == 0x0a: - out += "\n" + out += b"\n" isnewline = 1 continue if oc < 0x20 or oc >= 0x7f and oc != 0x09: - out += "<%02x>" % oc + out += b"<%02x>" % oc continue - out += c + out.append(oc) - if (sys.version_info > (3, 0)): - sys.stdout.buffer.write(out) - else: - sys.stdout.write(out) + sys.stdout.write(out.decode()) sys.stdout.flush() logfile.write(out) logfile.flush() -- 2.31.1

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SeaBIOS booting issue on Asus P2B-LS board with coreboot
by Keith Hui Dec. 27, 2021

Dec. 27, 2021

Hi all, (All was done with SeaBIOS 1.15.0) I was testing a coreboot change when suddenly both of my two P2B-LS boards failed to boot. I have been booting off a Maxtor 6E040L0 hard drive when the boot started to stall after SeaBIOS. Took me hours but eventually I found a line in my serial log that there has been a DMA timeout. I had to turn UDMA off from coreboot to resolve. I landed a patch there to enable UDMA on all 4 drives by default, thinking it was the reasonable thing to do and should have worked. Does SeaBIOS manage or enable UDMA itself? Is there more to UDMA than just enable it in PIIX4? And while I'm troubleshooting the boot, I plugged in a Promise SATA150 tx2plus card and moved the hard drive there. SeaBIOS caught and and ran its option ROM just fine, but didn't bother booting from it, instead going to the iPXE ROM I managed to insert after freeing enough space in the flash image. Why? Thanks Keith

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[PATCH v4 0/3] virtio-blk: add feature VIRTIO_BLK_F_SIZE_MAX
by Andy Pei Dec. 20, 2021

Dec. 20, 2021

if driver reads data larger than VIRTIO_BLK_F_SIZE_MAX, it will cause some issue to the DMA engine. So add VIRTIO_BLK_F_SIZE_MAX feature support, when upper software wants to read data larger than VIRTIO_BLK_F_SIZE_MAX, virtio-blk driver split one large request into multiple smaller ones. Andy Pei (3): virtio-blk: add feature VIRTIO_BLK_F_SIZE_MAX and VIRTIO_BLK_F_SEG_MAX virtio-blk: abstract a function named virtio_blk_op_one_segment to handle r/w request virtio-blk.: split large IO according to size_max src/block.h | 2 + src/hw/virtio-blk.c | 128 +++++++++++++++++++++++++++++++++++++++++----------- src/hw/virtio-blk.h | 3 ++ 3 files changed, 107 insertions(+), 26 deletions(-) -- 1.8.3.1

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[PATCH] memmap: Fix gcc out-of-bounds warning
by Kevin O'Connor Dec. 19, 2021

Dec. 19, 2021

Use a different definition for the linker script symbol to avoid a gcc warning. Signed-off-by: Kevin O'Connor <kevin(a)koconnor.net> --- src/memmap.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/memmap.h b/src/memmap.h index 22bd4bc..32ca265 100644 --- a/src/memmap.h +++ b/src/memmap.h @@ -15,7 +15,7 @@ static inline void *memremap(u32 addr, u32 len) { } // Return the value of a linker script symbol (see scripts/layoutrom.py) -#define SYMBOL(SYM) ({ extern char SYM; (u32)&SYM; }) +#define SYMBOL(SYM) ({ extern char SYM[]; (u32)SYM; }) #define VSYMBOL(SYM) ((void*)SYMBOL(SYM)) #endif // memmap.h -- 2.31.1

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[PATCH] vgasrc: Don't use VAR16 in header files to fix gcc warning
by Kevin O'Connor Dec. 18, 2021

Dec. 18, 2021

Some versions of gcc complain when VAR16 is used in both the header and C files - use only in the C file to fix the warning. Signed-off-by: Kevin O'Connor <kevin(a)koconnor.net> --- vgasrc/svgamodes.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/vgasrc/svgamodes.h b/vgasrc/svgamodes.h index 782d30b..6ac1d64 100644 --- a/vgasrc/svgamodes.h +++ b/vgasrc/svgamodes.h @@ -6,7 +6,7 @@ struct generic_svga_mode { struct vgamode_s info; }; -extern struct generic_svga_mode svga_modes[] VAR16; -extern unsigned int svga_mcount VAR16; +extern struct generic_svga_mode svga_modes[]; +extern unsigned int svga_mcount; #endif /* __SVGAMODES_H */ -- 2.31.1

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[PATCH] svgamodes: add standard 4k modes
by Gerd Hoffmann Dec. 18, 2021

Dec. 18, 2021

Add all three 4k modes. Computer monitors typically use the first one (3840x2160). Add 16 and 32 bpp variants. 24bpp is dead these days, and software which is so old that still uses those modes most likely doesn't even know what 4k is. Signed-off-by: Gerd Hoffmann <kraxel(a)redhat.com> --- vgasrc/svgamodes.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/vgasrc/svgamodes.c b/vgasrc/svgamodes.c index 6e494c719f39..2543b9545524 100644 --- a/vgasrc/svgamodes.c +++ b/vgasrc/svgamodes.c @@ -92,5 +92,13 @@ struct generic_svga_mode svga_modes[] VAR16 = { { 0x196, { MM_DIRECT, 2560, 1440, 16, 8, 16, SEG_GRAPH } }, { 0x197, { MM_DIRECT, 2560, 1440, 24, 8, 16, SEG_GRAPH } }, { 0x198, { MM_DIRECT, 2560, 1440, 32, 8, 16, SEG_GRAPH } }, + + /* 4k modes */ + { 0x199, { MM_DIRECT, 3840, 2160, 16, 8, 16, SEG_GRAPH } }, + { 0x19a, { MM_DIRECT, 3840, 2160, 32, 8, 16, SEG_GRAPH } }, + { 0x19b, { MM_DIRECT, 4096, 2160, 16, 8, 16, SEG_GRAPH } }, + { 0x19c, { MM_DIRECT, 4096, 2160, 32, 8, 16, SEG_GRAPH } }, + { 0x19d, { MM_DIRECT, 5120, 2160, 16, 8, 16, SEG_GRAPH } }, + { 0x19e, { MM_DIRECT, 5120, 2160, 32, 8, 16, SEG_GRAPH } }, }; unsigned int svga_mcount VAR16 = ARRAY_SIZE(svga_modes); -- 2.33.1

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