[src/trunk]: src/sys/arch/mvme68k/mvme68k Fix the code which probes the memor...

[scw <scw%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/82a7713c3dbe
branches:  trunk
changeset: 499638:82a7713c3dbe
user:      scw <scw%NetBSD.org@localhost>
date:      Sat Nov 25 11:25:07 2000 +0000

description:
Fix the code which probes the memory controller ASICs. We can now
deal with the 2nd one not being present.

diffstat:

 sys/arch/mvme68k/mvme68k/locore.s |  50 ++++++++++++--------------------------
 1 files changed, 16 insertions(+), 34 deletions(-)

diffs (97 lines):

diff -r a373489c5485 -r 82a7713c3dbe sys/arch/mvme68k/mvme68k/locore.s
--- a/sys/arch/mvme68k/mvme68k/locore.s Sat Nov 25 07:58:07 2000 +0000
+++ b/sys/arch/mvme68k/mvme68k/locore.s Sat Nov 25 11:25:07 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: locore.s,v 1.68 2000/11/21 22:08:04 scw Exp $  */
+/*     $NetBSD: locore.s,v 1.69 2000/11/25 11:25:07 scw Exp $  */
 
 /*
  * Copyright (c) 1988 University of Utah.
@@ -419,13 +419,6 @@
         * Figure out the size of onboard DRAM by querying
         * the memory controller ASIC(s)
         */
-       movql   #0x07,d0
-#if 0
-       /*
-        * We'd like to do it this way, but for some reason which I
-        * can't quite fathom, accessing a non-existant MEM* controller
-        * locks the machine up solid...
-        */
        lea     0xfff43008,a0           | MEMC040/MEMECC Controller #1
        bsr     memc040read
        movl    d0,d1
@@ -433,14 +426,6 @@
        lea     0xfff43108,a0           | MEMC040/MEMECC Controller #2
        bsr     memc040read
        addl    d0,d1
-#else
-       /*
-        * For now, just assume there's only the one controller
-        */
-       andb    0xfff43008,d0           | MEMC040/MEMECC Controller #1
-       movl    #0x00400000,d1
-       lsll    d0,d1
-#endif
 
 Lis1xx_common:
        /* Save our ethernet address */
@@ -638,31 +623,29 @@
 
        jra     _C_LABEL(main)          | main()
 
-#if 0
 #if defined(MVME162) || defined(MVME167) || defined(MVME172) || defined(MVME177)
 /*
  * Probe for a memory controller ASIC (MEMC040 or MEMECC) at the
  * address in a0. If found, return the size in bytes of any RAM
  * controlled by the ASIC in d0. Otherwise return zero.
- *
- * Note: This does not yet work as expected. Accessing a non-existant
- *       ASIC generates something a bit more complex than a Buserr.
  */
 ASLOCAL(memc040read)
-       moveml  #0xC0C0,sp@-            | save scratch regs
+       moveml  d1-d2/a1-a2,sp@-        | save scratch regs
+       movc    vbr,d2                  | Save vbr
+       RELOC(vectab,a2)                | Install our own vectab, temporarily
+       movc    a2,vbr
        ASRELOC(Lmemc040berr,a1)        | get address of bus error handler
-       movl    a1,d1
-       movc    vbr,a1                  | Fetch VBR address
-       movl    a1@(8),sp@-             | Save current bus error handler addr
-       movl    d1,a1@(8)               | Install our own handler
-       movl    sp,d1                   | Save current stack pointer value
-       movql   #0x07,d0
-       andb    a0@,d0                  | Access MEMC040/MEMECC
-       ASRELOC(memc_msiz,a0)
-       movl    a0@(d0:w:4),d0          | Compute how many bytes of RAM
+       movl    a2@(8),sp@-             | Save current bus error handler addr
+       movl    a1,a2@(8)               | Install our own handler
+       movl    sp,d0                   | Save current stack pointer value
+       movql   #0x07,d1
+       andb    a0@,d1                  | Access MEMC040/MEMECC
+       movl    #0x400000,d0
+       lsll    d1,d0                   | Convert to memory size, in bytes
 Lmemc040ret:
-       movl    sp@+,a1@(8)             | Restore original bus error handler
-       moveml  sp@+,#0x0303
+       movc    d2,vbr                  | Restore original vbr
+       movl    sp@+,a2@(8)             | Restore original bus error handler
+       moveml  sp@+,d1-d2/a1-a2
        rts
 /*
  * If the memory controller doesn't exist, we get a bus error trying
@@ -670,11 +653,10 @@
  * ditch the exception frame and return as normal.
  */
 Lmemc040berr:
+       movl    d0,sp                   | Get rid of the exception frame
        movql   #0,d0                   | No ASIC at this location, then!
-       movl    d1,sp                   | Get rid of the exception frame
        bra     Lmemc040ret             | Done
 #endif
-#endif /* if 0 */
 
 /*
  * proc_trampoline: call function in register a2 with a3 as an arg