parisc: Add runtime check to prevent PA2.0 kernels on PA1.x machines

[ Upstream commit 591d2108f3 ]

If a 32-bit kernel was compiled for PA2.0 CPUs, it won't be able to run
on machines with PA1.x CPUs. Add a check and bail out early if a PA1.x
machine is detected.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Helge Deller 2022-08-21 14:49:58 +02:00 committed by Greg Kroah-Hartman
parent deb2c9c077
commit 27092358e9

View File

@ -22,7 +22,7 @@
#include <linux/init.h>
#include <linux/pgtable.h>
.level PA_ASM_LEVEL
.level 1.1
__INITDATA
ENTRY(boot_args)
@ -69,6 +69,47 @@ $bss_loop:
stw,ma %arg2,4(%r1)
stw,ma %arg3,4(%r1)
#if !defined(CONFIG_64BIT) && defined(CONFIG_PA20)
/* This 32-bit kernel was compiled for PA2.0 CPUs. Check current CPU
* and halt kernel if we detect a PA1.x CPU. */
ldi 32,%r10
mtctl %r10,%cr11
.level 2.0
mfctl,w %cr11,%r10
.level 1.1
comib,<>,n 0,%r10,$cpu_ok
load32 PA(msg1),%arg0
ldi msg1_end-msg1,%arg1
$iodc_panic:
copy %arg0, %r10
copy %arg1, %r11
load32 PA(init_stack),%sp
#define MEM_CONS 0x3A0
ldw MEM_CONS+32(%r0),%arg0 // HPA
ldi ENTRY_IO_COUT,%arg1
ldw MEM_CONS+36(%r0),%arg2 // SPA
ldw MEM_CONS+8(%r0),%arg3 // layers
load32 PA(__bss_start),%r1
stw %r1,-52(%sp) // arg4
stw %r0,-56(%sp) // arg5
stw %r10,-60(%sp) // arg6 = ptr to text
stw %r11,-64(%sp) // arg7 = len
stw %r0,-68(%sp) // arg8
load32 PA(.iodc_panic_ret), %rp
ldw MEM_CONS+40(%r0),%r1 // ENTRY_IODC
bv,n (%r1)
.iodc_panic_ret:
b . /* wait endless with ... */
or %r10,%r10,%r10 /* qemu idle sleep */
msg1: .ascii "Can't boot kernel which was built for PA8x00 CPUs on this machine.\r\n"
msg1_end:
$cpu_ok:
#endif
.level PA_ASM_LEVEL
/* Initialize startup VM. Just map first 16/32 MB of memory */
load32 PA(swapper_pg_dir),%r4
mtctl %r4,%cr24 /* Initialize kernel root pointer */