[OpenBIOS] [commit] r962 - in trunk/openbios-devel: arch/ppc/qemu config/examples

repository service svn at openbios.org
Sat Nov 20 22:14:59 CET 2010 

Author: afaerber
Date: Sat Nov 20 22:14:59 2010
New Revision: 962
URL: http://tracker.coreboot.org/trac/openbios/changeset/962

Log:
ppc: Turn 32-bit ppc64 into a config option, to be deprecated

Having legacy 64-bit support as an option allows users to
disable it and test the 32-bit only version prior to official
removal of legacy 64-bit support.

Fork single-bitness macros EXCEPTION_{PREAMBLE,EPILOGUE}:
Use assembler macros for things that are constant to avoid
; and \, and use preprocessor macros to handle differences.
Adopt QEMU coding style for new code.

Functional changes for ppc64:
* Don't clear MSR in preamble
  in order to stay in Sixty-Four Bit Mode.
* Just save the minimum number of registers
  since 64-bit code will save the full registers.
* Reserve 48 bytes of stack frame space for ppc64,
  according to 64-bit PowerPC ELF ABI supplement 1.9.
* Use rfid via RFI macro.

v2:
* Remove inaccurate comment on unused stack location.
* Add explanatory comments for #else and #endif.

Cc: Alexander Graf <agraf at suse.de>
Signed-off-by: Andreas Färber <andreas.faerber at web.de>

Modified:
   trunk/openbios-devel/arch/ppc/qemu/init.c
   trunk/openbios-devel/arch/ppc/qemu/start.S
   trunk/openbios-devel/config/examples/ppc_config.xml

Modified: trunk/openbios-devel/arch/ppc/qemu/init.c
==============================================================================
--- trunk/openbios-devel/arch/ppc/qemu/init.c	Wed Nov 17 20:36:18 2010	(r961)
+++ trunk/openbios-devel/arch/ppc/qemu/init.c	Sat Nov 20 22:14:59 2010	(r962)
@@ -303,6 +303,7 @@
     fword("finish-device");
 }
 
+#ifdef CONFIG_PPC_64BITSUPPORT
 /* In order to get 64 bit aware handlers that rescue all our
    GPRs from getting truncated to 32 bits, we need to patch the
    existing handlers so they jump to our 64 bit aware ones. */
@@ -322,6 +323,7 @@
     asm ( "icbi 0, %0" : : "r"(dsi) );
     asm ( "icbi 0, %0" : : "r"(isi) );
 }
+#endif
 
 static void
 cpu_970_init(const struct cpudef *cpu)
@@ -341,10 +343,12 @@
 
     fword("finish-device");
 
+#ifdef CONFIG_PPC_64BITSUPPORT
     /* The 970 is a PPC64 CPU, so we need to activate
      * 64bit aware interrupt handlers */
 
     ppc64_patch_handlers();
+#endif
 
     /* The 970 also implements the HIOR which we need to set to 0 */
 

Modified: trunk/openbios-devel/arch/ppc/qemu/start.S
==============================================================================
--- trunk/openbios-devel/arch/ppc/qemu/start.S	Wed Nov 17 20:36:18 2010	(r961)
+++ trunk/openbios-devel/arch/ppc/qemu/start.S	Sat Nov 20 22:14:59 2010	(r962)
@@ -14,6 +14,7 @@
  *
  */
 
+#include "autoconf.h"
 #include "asm/asmdefs.h"
 #include "asm/processor.h"
 
@@ -24,6 +25,8 @@
 #define ILLEGAL_VECTOR( v )	.org __vectors + v ; vector__##v: bl trap_error ;
 #define VECTOR( v, dummystr )	.org __vectors + v ; vector__##v
 
+#ifdef CONFIG_PPC_64BITSUPPORT
+
 /* We're trying to use the same code for the ppc32 and ppc64 handlers here.
  * On ppc32 we only save/restore the registers, C considers volatile.
  *
@@ -176,6 +179,87 @@
 #undef stl
 #undef ll
 
+#else /* !CONFIG_PPC_64BITSUPPORT */
+
+#ifdef __powerpc64__
+
+#define ULONG_SIZE 8
+#define STACKFRAME_MINSIZE 48
+#define stl std
+#define ll  ld
+
+#else
+
+#define ULONG_SIZE 4
+#define STACKFRAME_MINSIZE 16
+#define stl stw
+#define ll  lwz
+
+#endif
+
+.macro EXCEPTION_PREAMBLE
+    mtsprg1 r1 /* scratch */
+    mfsprg0 r1 /* exception stack in sprg0 */
+    addi    r1, r1, -(20 * ULONG_SIZE) /* push exception frame */
+
+    stl     r0,  ( 0 * ULONG_SIZE)(r1) /* save r0 */
+    mfsprg1 r0
+    stl     r0,  ( 1 * ULONG_SIZE)(r1) /* save r1 */
+    stl     r2,  ( 2 * ULONG_SIZE)(r1) /* save r2 */
+    stl     r3,  ( 3 * ULONG_SIZE)(r1) /* save r3 */
+    stl     r4,  ( 4 * ULONG_SIZE)(r1)
+    stl     r5,  ( 5 * ULONG_SIZE)(r1)
+    stl     r6,  ( 6 * ULONG_SIZE)(r1)
+    stl     r7,  ( 7 * ULONG_SIZE)(r1)
+    stl     r8,  ( 8 * ULONG_SIZE)(r1)
+    stl     r9,  ( 9 * ULONG_SIZE)(r1)
+    stl     r10, (10 * ULONG_SIZE)(r1)
+    stl     r11, (11 * ULONG_SIZE)(r1)
+    stl     r12, (12 * ULONG_SIZE)(r1)
+
+    mflr    r0
+    stl     r0,  (13 * ULONG_SIZE)(r1)
+    mfcr    r0
+    stl     r0,  (14 * ULONG_SIZE)(r1)
+    mfctr   r0
+    stl     r0,  (15 * ULONG_SIZE)(r1)
+    mfxer   r0
+    stl     r0,  (16 * ULONG_SIZE)(r1)
+
+    addi r1, r1, -STACKFRAME_MINSIZE /* C ABI saves LR and SP */
+.endm
+
+.macro EXCEPTION_EPILOGUE
+    addi r1, r1,  STACKFRAME_MINSIZE /* pop ABI frame */
+
+    ll    r0,  (13 * ULONG_SIZE)(r1)
+    mtlr  r0
+    ll    r0,  (14 * ULONG_SIZE)(r1)
+    mtcr  r0
+    ll    r0,  (15 * ULONG_SIZE)(r1)
+    mtctr r0
+    ll    r0,  (16 * ULONG_SIZE)(r1)
+    mtxer r0
+
+    ll    r0,  ( 0 * ULONG_SIZE)(r1)
+    ll    r2,  ( 2 * ULONG_SIZE)(r1)
+    ll    r3,  ( 3 * ULONG_SIZE)(r1)
+    ll    r4,  ( 4 * ULONG_SIZE)(r1)
+    ll    r5,  ( 5 * ULONG_SIZE)(r1)
+    ll    r6,  ( 6 * ULONG_SIZE)(r1)
+    ll    r7,  ( 7 * ULONG_SIZE)(r1)
+    ll    r8,  ( 8 * ULONG_SIZE)(r1)
+    ll    r9,  ( 9 * ULONG_SIZE)(r1)
+    ll    r10, (10 * ULONG_SIZE)(r1)
+    ll    r11, (11 * ULONG_SIZE)(r1)
+    ll    r12, (12 * ULONG_SIZE)(r1)
+
+    ll    r1,  ( 1 * ULONG_SIZE)(r1) /* restore stack at last */
+    RFI
+.endm
+
+#endif /* !CONFIG_PPC_64BITSUPPORT */
+
 /************************************************************************/
 /*	vectors								*/
 /************************************************************************/
@@ -253,6 +337,8 @@
 ILLEGAL_VECTOR( 0x1600 )
 ILLEGAL_VECTOR( 0x1700 )
 
+#ifdef CONFIG_PPC_64BITSUPPORT
+
 VECTOR( 0x2000, "DSI_64" ):
 	EXCEPTION_PREAMBLE_64
 	LOAD_REG_IMMEDIATE(r3, dsi_exception)
@@ -267,6 +353,8 @@
 	bctrl
 	EXCEPTION_EPILOGUE_64
 
+#endif
+
 GLOBL(__vectors_end):
 
 /************************************************************************/
@@ -275,7 +363,7 @@
 
 GLOBL(_entry):
 
-#ifndef __powerpc64__
+#ifdef CONFIG_PPC_64BITSUPPORT
 	/* clear MSR, disable MMU */
 
 	li	r0,0

Modified: trunk/openbios-devel/config/examples/ppc_config.xml
==============================================================================
--- trunk/openbios-devel/config/examples/ppc_config.xml	Wed Nov 17 20:36:18 2010	(r961)
+++ trunk/openbios-devel/config/examples/ppc_config.xml	Sat Nov 20 22:14:59 2010	(r962)
@@ -57,6 +57,7 @@
   <option name="CONFIG_DEBUG_FS" type="boolean" value="false"/>
 
   <!-- Miscellaneous -->
+  <option name="CONFIG_PPC_64BITSUPPORT" type="boolean" value="true"/>
   <option name="CONFIG_LINUXBIOS" type="boolean" value="false"/>
   <option name="CONFIG_RTAS" type="boolean" value="false"/>

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