Module Name: src
Committed By: thorpej
Date: Wed Feb 17 23:21:47 UTC 2021
Modified Files:
src/sys/arch/macppc/macppc: locore.S
src/sys/arch/ofppc/ofppc: locore.S
Log Message:
Document the register state on entry per the OpenFirmware PowerPC CPU
bindings. Ensure we save off %r6 and %r7 before calling any other
functions.
To generate a diff of this commit:
cvs rdiff -u -r1.77 -r1.78 src/sys/arch/macppc/macppc/locore.S
cvs rdiff -u -r1.50 -r1.51 src/sys/arch/ofppc/ofppc/locore.S
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/macppc/macppc/locore.S
diff -u src/sys/arch/macppc/macppc/locore.S:1.77 src/sys/arch/macppc/macppc/locore.S:1.78
--- src/sys/arch/macppc/macppc/locore.S:1.77 Sat Feb 13 02:17:02 2021
+++ src/sys/arch/macppc/macppc/locore.S Wed Feb 17 23:21:46 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.77 2021/02/13 02:17:02 thorpej Exp $ */
+/* $NetBSD: locore.S,v 1.78 2021/02/17 23:21:46 thorpej Exp $ */
/*
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
@@ -77,10 +77,23 @@ _C_LABEL(kernel_text):
/*
* Startup entry. Note, this must be the first thing in the text
* segment!
+ *
+ * Register state as transfer is passed from OpenFirmware / boot loader:
+ *
+ * %r1 Stack provided by OpenFirmware / boot loader
+ * %r3 Reserved for platform binding (unused here)
+ * %r4 Reserved for platform binding (unused here)
+ * %r5 OpenFirmware client entry point
+ * %r6 Arguments
+ * %r7 Arguments length
*/
.text
.globl __start
__start:
+ /* Save off arguments that we need preserved. */
+ mr %r13,%r6
+ mr %r14,%r7
+
bl _C_LABEL(ofwinit) /* init OF */
li %r0,0
@@ -89,8 +102,6 @@ __start:
#endif
isync
- mr %r13,%r6
- mr %r14,%r7
bl _C_LABEL(cpu_model_init) /* init oeacpufeat */
/* compute end of kernel memory */
Index: src/sys/arch/ofppc/ofppc/locore.S
diff -u src/sys/arch/ofppc/ofppc/locore.S:1.50 src/sys/arch/ofppc/ofppc/locore.S:1.51
--- src/sys/arch/ofppc/ofppc/locore.S:1.50 Sun Jul 15 05:16:43 2018
+++ src/sys/arch/ofppc/ofppc/locore.S Wed Feb 17 23:21:47 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: locore.S,v 1.50 2018/07/15 05:16:43 maxv Exp $ */
+/* $NetBSD: locore.S,v 1.51 2021/02/17 23:21:47 thorpej Exp $ */
/*
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
@@ -75,13 +75,24 @@ _C_LABEL(kernel_text):
/*
* Startup entry. Note, this must be the first thing in the text
* segment!
+ *
+ * Register state as transfer is passed from OpenFirmware / boot loader:
+ *
+ * %r1 Stack provided by OpenFirmware / boot loader
+ * %r3 Reserved for platform binding (unused here)
+ * %r4 Reserved for platform binding (unused here)
+ * %r5 OpenFirmware client entry point
+ * %r6 Arguments
+ * %r7 Arguments length
*/
.text
.globl __start
__start:
+ /* Save off arguments that we need preserved. */
mr %r13,%r6
mr %r14,%r7
- bl _C_LABEL(ofwinit) /* init our OF hooks */
+
+ bl _C_LABEL(ofwinit) /* init OF */
li %r0,0
mtmsr %r0 /* Disable FPU/MMU/exceptions */
