85xx: Additional fixes and cleanup of MP code

* adjust __spin_table alignment to match ePAPR v0.94 spec
* loop over all cpus when determing who is up.  This fixes an issue if
  the "boot cpu" isn't core0.  The "boot cpu" will already be in the
  cpu_up_mask so there is no harm
* Added some protection in the code to ensure proper behavior.  These
  changes are explicitly needed but don't hurt:
  - Added eieio to ensure the "hot word" of the table is written after
    all other table updates have occurred.
  - Added isync to ensure we don't prefetch loading of table entries
    until we a released

These issues we raised by Dave Liu.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This commit is contained in:
Kumar Gala 2008-04-28 02:24:04 -05:00 committed by Andrew Fleming-AFLEMING
parent fd2d2d1025
commit cf6cc01427
2 changed files with 7 additions and 2 deletions

View File

@ -103,6 +103,10 @@ int cpu_release(int nr, int argc, char *argv[])
}
table[BOOT_ENTRY_ADDR_UPPER] = (u32)(boot_addr >> 32);
/* ensure all table updates complete before final address write */
eieio();
table[BOOT_ENTRY_ADDR_LOWER] = (u32)(boot_addr & 0xffffffff);
return 0;
@ -153,7 +157,7 @@ static void pq3_mp_up(unsigned long bootpg)
/* wait for everyone */
while (timeout) {
int i;
for (i = 1; i < CONFIG_NR_CPUS; i++) {
for (i = 0; i < CONFIG_NR_CPUS; i++) {
if (table[i * NUM_BOOT_ENTRY + BOOT_ENTRY_ADDR_LOWER])
cpu_up_mask |= (1 << i);
};

View File

@ -114,6 +114,7 @@ __secondary_start_page:
lwz r4,ENTRY_ADDR_LOWER(r10)
andi. r11,r4,1
bne 2b
isync
/* get the upper bits of the addr */
lwz r11,ENTRY_ADDR_UPPER(r10)
@ -169,7 +170,7 @@ __secondary_start_page:
mtspr SPRN_SRR1,r13
rfi
.align 3
.align L1_CACHE_SHIFT
.globl __spin_table
__spin_table:
.space CONFIG_NR_CPUS*ENTRY_SIZE