From 09d240e074ad22a3d8f6e4dbe088e8959ffad26b Mon Sep 17 00:00:00 2001
From: kettenis <kettenis@openbsd.org>
Date: Wed, 29 Jun 2022 07:51:54 +0000
Subject: [PATCH] Add support for using non-standard UARTs (such as the
 Synopsys DesignWare UART found on AMD's Ryzen Embedded V1000 family) as an
 early console. This requires additional parameters to be passed by the
 bootloader to the kernel so it changes the struct for the BOOTARG_CONSDEV
 boot argument. The old struct will still be supported until OpenBSD 7.3 has
 been released such that new kernels boot with the old bootloader.

ok anton@, deraadt@
---
 sys/arch/amd64/amd64/machdep.c   | 33 ++++++++++++++++++++++++++++++--
 sys/arch/amd64/include/biosvar.h | 16 ++++++++++++++--
 2 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/sys/arch/amd64/amd64/machdep.c b/sys/arch/amd64/amd64/machdep.c
index d7d36c5adab..53e2e0a0aee 100644
--- a/sys/arch/amd64/amd64/machdep.c
+++ b/sys/arch/amd64/amd64/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.277 2022/02/01 20:29:53 deraadt Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.278 2022/06/29 07:51:54 kettenis Exp $	*/
 /*	$NetBSD: machdep.c,v 1.3 2003/05/07 22:58:18 fvdl Exp $	*/
 
 /*-
@@ -1945,7 +1945,7 @@ getbootinfo(char *bootinfo, int bootinfo_size)
 			/* generated by i386 boot loader */
 			break;
 		case BOOTARG_CONSDEV:
-			if (q->ba_size >= sizeof(bios_consdev_t) +
+			if (q->ba_size > sizeof(bios_oconsdev_t) +
 			    offsetof(struct _boot_args32, ba_arg)) {
 #if NCOM > 0
 				bios_consdev_t *cdp =
@@ -1953,6 +1953,35 @@ getbootinfo(char *bootinfo, int bootinfo_size)
 				static const int ports[] =
 				    { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
 				int unit = minor(cdp->consdev);
+				uint64_t consaddr = cdp->consaddr;
+				if (consaddr == -1 && unit >= 0 &&
+				    unit < nitems(ports))
+					consaddr = ports[unit];
+				if (major(cdp->consdev) == 8 &&
+				    consaddr != -1) {
+					comconsunit = unit;
+					comconsaddr = consaddr;
+					comconsrate = cdp->conspeed;
+					comconsfreq = cdp->consfreq;
+					comcons_reg_width = cdp->reg_width;
+					comcons_reg_shift = cdp->reg_shift;
+					if (cdp->flags & BCD_MMIO)
+						comconsiot = X86_BUS_SPACE_MEM;
+					else
+						comconsiot = X86_BUS_SPACE_IO;
+				}
+#endif
+#ifdef BOOTINFO_DEBUG
+				printf(" console 0x%x:%d",
+				    cdp->consdev, cdp->conspeed);
+#endif
+			} else {
+#if NCOM > 0
+				bios_oconsdev_t *cdp =
+				    (bios_oconsdev_t*)q->ba_arg;
+				static const int ports[] =
+				    { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
+				int unit = minor(cdp->consdev);
 				int consaddr = cdp->consaddr;
 				if (consaddr == -1 && unit >= 0 &&
 				    unit < nitems(ports))
diff --git a/sys/arch/amd64/include/biosvar.h b/sys/arch/amd64/include/biosvar.h
index 893fbc23caf..8fe6e29c2a9 100644
--- a/sys/arch/amd64/include/biosvar.h
+++ b/sys/arch/amd64/include/biosvar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: biosvar.h,v 1.27 2019/11/29 16:16:19 kettenis Exp $	*/
+/*	$OpenBSD: biosvar.h,v 1.28 2022/06/29 07:51:54 kettenis Exp $	*/
 
 /*
  * Copyright (c) 1997-1999 Michael Shalayeff
@@ -162,11 +162,23 @@ typedef struct _bios_pciinfo {
 
 #define	BOOTARG_CONSDEV	5
 typedef struct _bios_consdev {
+	dev_t		consdev;
+	int		conspeed;
+	uint64_t	consaddr;
+	int		consfreq;
+	uint32_t	flags;
+#define BCD_MMIO	0x00000001	/* Memory Mapped IO */
+	int		reg_width;
+	int		reg_shift;
+} __packed bios_consdev_t;
+
+/* Old interface; remove after OpenBSD 7.3 is released */
+typedef struct _bios_oconsdev {
 	dev_t	consdev;
 	int	conspeed;
 	int	consaddr;
 	int	consfreq;
-} __packed bios_consdev_t;
+} __packed bios_oconsdev_t;
 
 #define BOOTARG_BOOTMAC	7
 typedef struct _bios_bootmac {
-- 
2.20.1