I noticed that unlike amd64 and i386, arm64's bootaa64 supports
loading a kernel from a non-'a' partition (i.e. boot> sd0d:/bsd),
however the kernel does not respect that partition when mounting the
root filesystem. It looks like this is caused by hard-coding 'part =
0' in arm64's autoconf.c.

Digging further, it appears that at one point this behavior was present:

https://marc.info/?l=openbsd-cvs&m=154703994927978
(git cfd4bff0313b7a29ea82f9484862326f1c6b2643)

It was later removed as part of (I believe) a general clean up:

https://marc.info/?l=openbsd-cvs&m=160466957311120
(git 35fd387b3e5263176046603ff3e402ceeef58cf3)

My attempt at a minimally-invasive patch to restore this functionality
follows. Tested on RPi 3B+ and 3B, as those are the only arm64 devices
I have. May not be idiomatic/good code. Thanks.

Brian Conway

diff --git sys/arch/arm64/arm64/autoconf.c sys/arch/arm64/arm64/autoconf.c
index bda3cb3f6b0..5f68d2665e1 100644
--- sys/arch/arm64/arm64/autoconf.c
+++ sys/arch/arm64/arm64/autoconf.c
@@ -75,11 +75,23 @@ diskconf(void)
 {
 #if defined(NFSCLIENT)
     extern uint8_t *bootmac;
-    dev_t tmpdev = NODEV;
 #endif
+    dev_t tmpdev = NODEV;
+    extern char bootargs[256];
+    char *p;
+    size_t len;
     struct device *bootdv = NULL;
     int part = 0;

+    /* Extract part from <device>:/bsd */
+    if ((p = strchr(bootargs, ':')) != NULL)
+        len = p - bootargs;
+    else
+        len = strlen(bootargs);
+    bootdv = parsedisk(bootargs, len, 0, &tmpdev);
+    if (tmpdev != NODEV)
+        part = DISKPART(tmpdev);
+
 #if defined(NFSCLIENT)
     if (bootmac) {
         struct ifnet *ifp;
diff --git sys/arch/arm64/arm64/machdep.c sys/arch/arm64/arm64/machdep.c
index c84cf6d9b13..2eb5da44409 100644
--- sys/arch/arm64/arm64/machdep.c
+++ sys/arch/arm64/arm64/machdep.c
@@ -1130,7 +1130,7 @@ process_kernel_args(void)

     boot_args = cp;

-    printf("bootargs: %s\n", boot_args);
+    printf("boot_args: %s\n", boot_args);

     /* Setup pointer to boot flags */
     while (*cp != '-')

dmesg (7.0-stable):

OpenBSD 7.0-stable (GENERIC.MP) #6: Mon Nov 15 21:50:51 UTC 2021
    
[email protected]:/usr/src/sys/arch/arm64/compile/GENERIC.MP
real mem  = 970907648 (925MB)
avail mem = 908574720 (866MB)
random: good seed from bootblocks
mainbus0 at root: Raspberry Pi 3 Model B Plus Rev 1.3
cpu0 at mainbus0 mpidr 0: ARM Cortex-A53 r0p4
cpu0: 32KB 64b/line 2-way L1 VIPT I-cache, 32KB 64b/line 4-way L1 D-cache
cpu0: 512KB 64b/line 16-way L2 cache
cpu0: CRC32,ASID16
cpu1 at mainbus0 mpidr 1: ARM Cortex-A53 r0p4
cpu1: 32KB 64b/line 2-way L1 VIPT I-cache, 32KB 64b/line 4-way L1 D-cache
cpu1: 512KB 64b/line 16-way L2 cache
cpu1: CRC32,ASID16
cpu2 at mainbus0 mpidr 2: ARM Cortex-A53 r0p4
cpu2: 32KB 64b/line 2-way L1 VIPT I-cache, 32KB 64b/line 4-way L1 D-cache
cpu2: 512KB 64b/line 16-way L2 cache
cpu2: CRC32,ASID16
cpu3 at mainbus0 mpidr 3: ARM Cortex-A53 r0p4
cpu3: 32KB 64b/line 2-way L1 VIPT I-cache, 32KB 64b/line 4-way L1 D-cache
cpu3: 512KB 64b/line 16-way L2 cache
cpu3: CRC32,ASID16
efi0 at mainbus0: UEFI 2.8
efi0: Das U-Boot rev 0x20210700
apm0 at mainbus0
simplefb0 at mainbus0: 656x416, 32bpp
wsdisplay0 at simplefb0 mux 1
wsdisplay0: screen 0-5 added (std, vt100 emulation)
"system" at mainbus0 not configured
"axi" at mainbus0 not configured
simplebus0 at mainbus0: "soc"
bcmclock0 at simplebus0
bcmmbox0 at simplebus0
bcmgpio0 at simplebus0
bcmaux0 at simplebus0
bcmdmac0 at simplebus0: DMA0 DMA2 DMA4 DMA5 DMA8 DMA9 DMA10
bcmintc0 at simplebus0
pluart0 at simplebus0: console
bcmsdhost0 at simplebus0: 250 MHz base clock
sdmmc0 at bcmsdhost0: 4-bit, sd high-speed, mmc high-speed, dma
dwctwo0 at simplebus0
bcmdog0 at simplebus0
bcmrng0 at simplebus0
bcmtemp0 at simplebus0
"local_intc" at simplebus0 not configured
sdhc0 at simplebus0
sdhc0: SDHC 3.0, 200 MHz base clock
sdmmc1 at sdhc0: 4-bit, sd high-speed, mmc high-speed
"firmware" at simplebus0 not configured
"power" at simplebus0 not configured
"mailbox" at simplebus0 not configured
"gpiomem" at simplebus0 not configured
"fb" at simplebus0 not configured
"vcsm" at simplebus0 not configured
"clocks" at mainbus0 not configured
"phy" at mainbus0 not configured
"arm-pmu" at mainbus0 not configured
agtimer0 at mainbus0: 19200 kHz
"leds" at mainbus0 not configured
"fixedregulator_3v3" at mainbus0 not configured
"fixedregulator_5v0" at mainbus0 not configured
"bootloader" at mainbus0 not configured
dt: 445 probes
usb0 at dwctwo0: USB revision 2.0
sdmmc0: can't enable card
uhub0 at usb0 configuration 1 interface 0 "Broadcom DWC2 root hub" rev
2.00/1.00 addr 1
uhub1 at uhub0 port 1 configuration 1 interface 0 "Standard
Microsystems product 0x2514" rev 2.00/b.b3 addr 2
bwfm0 at sdmmc1 function 1
manufacturer 0x02d0, product 0xa9a6 at sdmmc1 function 2 not configured
manufacturer 0x02d0, product 0xa9a6 at sdmmc1 function 3 not configured
uhub2 at uhub1 port 1 configuration 1 interface 0 "Standard
Microsystems product 0x2514" rev 2.00/b.b3 addr 3
umass0 at uhub2 port 3 configuration 1 interface 0 "SanDisk Extreme"
rev 2.10/0.10 addr 4
umass0: using SCSI over Bulk-Only
scsibus0 at umass0: 2 targets, initiator 0
sd0 at scsibus0 targ 1 lun 0: <SanDisk, Extreme, 0001> removable
serial.07815580151429010265
sd0: 29923MB, 512 bytes/sector, 61282631 sectors
vscsi0 at root
scsibus1 at vscsi0: 256 targets
softraid0 at root
scsibus2 at softraid0: 256 targets
root on sd0a (7a70bc50720f4af9.a) swap on sd0b dump on sd0b
WARNING: CHECK AND RESET THE DATE!
gpio0 at bcmgpio0: 54 pins
bwfm0: failed loadfirmware of file
brcmfmac43455-sdio.raspberrypi,3-model-b-plus.bin
mue0 at uhub2 port 1 configuration 1 interface 0 "Standard
Microsystems LAN7800" rev 2.10/3.00 addr 5
mue0: LAN7800, address b8:27:eb:ab:12:75
ukphy0 at mue0 phy 1: Generic IEEE 802.3u media interface, rev. 2: OUI
0x0001f0, model 0x0013

Reply via email to