[PATCH] ppc64: remove HMT support
Anton Blanchard
anton at samba.org
Mon Feb 13 18:11:13 EST 2006
Hi,
HMT support is currently broken and needs to be reworked to play nicely
with the SMT scheduler. Remove the bit rotten bits for the time being.
I also updated an incorrect comment, we enter __secondary_hold with the
physical cpu id in r3.
Anton
Signed-off-by: Anton Blanchard <anton at samba.org>
---
Index: build/arch/powerpc/kernel/head_64.S
===================================================================
--- build.orig/arch/powerpc/kernel/head_64.S 2006-02-13 18:08:18.000000000 +1100
+++ build/arch/powerpc/kernel/head_64.S 2006-02-13 18:08:19.000000000 +1100
@@ -139,7 +139,7 @@ _GLOBAL(__secondary_hold)
ori r24,r24,MSR_RI
mtmsrd r24 /* RI on */
- /* Grab our linux cpu number */
+ /* Grab our physical cpu number */
mr r24,r3
/* Tell the master cpu we're here */
@@ -153,11 +153,6 @@ _GLOBAL(__secondary_hold)
cmpdi 0,r4,1
bne 100b
-#ifdef CONFIG_HMT
- SET_REG_IMMEDIATE(r4, .hmt_init)
- mtctr r4
- bctr
-#else
#ifdef CONFIG_SMP
LOAD_REG_IMMEDIATE(r4, .pSeries_secondary_smp_init)
mtctr r4
@@ -166,7 +161,6 @@ _GLOBAL(__secondary_hold)
#else
BUG_OPCODE
#endif
-#endif
/* This value is used to mark exception frames on the stack. */
.section ".toc","aw"
@@ -1810,22 +1804,6 @@ _STATIC(start_here_multiplatform)
ori r6,r6,MSR_RI
mtmsrd r6 /* RI on */
-#ifdef CONFIG_HMT
- /* Start up the second thread on cpu 0 */
- mfspr r3,SPRN_PVR
- srwi r3,r3,16
- cmpwi r3,0x34 /* Pulsar */
- beq 90f
- cmpwi r3,0x36 /* Icestar */
- beq 90f
- cmpwi r3,0x37 /* SStar */
- beq 90f
- b 91f /* HMT not supported */
-90: li r3,0
- bl .hmt_start_secondary
-91:
-#endif
-
/* The following gets the stack and TOC set up with the regs */
/* pointing to the real addr of the kernel stack. This is */
/* all done to support the C function call below which sets */
@@ -1939,77 +1917,8 @@ _STATIC(start_here_common)
bl .start_kernel
-_GLOBAL(hmt_init)
-#ifdef CONFIG_HMT
- LOAD_REG_IMMEDIATE(r5, hmt_thread_data)
- mfspr r7,SPRN_PVR
- srwi r7,r7,16
- cmpwi r7,0x34 /* Pulsar */
- beq 90f
- cmpwi r7,0x36 /* Icestar */
- beq 91f
- cmpwi r7,0x37 /* SStar */
- beq 91f
- b 101f
-90: mfspr r6,SPRN_PIR
- andi. r6,r6,0x1f
- b 92f
-91: mfspr r6,SPRN_PIR
- andi. r6,r6,0x3ff
-92: sldi r4,r24,3
- stwx r6,r5,r4
- bl .hmt_start_secondary
- b 101f
-
-__hmt_secondary_hold:
- LOAD_REG_IMMEDIATE(r5, hmt_thread_data)
- clrldi r5,r5,4
- li r7,0
- mfspr r6,SPRN_PIR
- mfspr r8,SPRN_PVR
- srwi r8,r8,16
- cmpwi r8,0x34
- bne 93f
- andi. r6,r6,0x1f
- b 103f
-93: andi. r6,r6,0x3f
-
-103: lwzx r8,r5,r7
- cmpw r8,r6
- beq 104f
- addi r7,r7,8
- b 103b
-
-104: addi r7,r7,4
- lwzx r9,r5,r7
- mr r24,r9
-101:
-#endif
- mr r3,r24
- b .pSeries_secondary_smp_init
-
-#ifdef CONFIG_HMT
-_GLOBAL(hmt_start_secondary)
- LOAD_REG_IMMEDIATE(r4,__hmt_secondary_hold)
- clrldi r4,r4,4
- mtspr SPRN_NIADORM, r4
- mfspr r4, SPRN_MSRDORM
- li r5, -65
- and r4, r4, r5
- mtspr SPRN_MSRDORM, r4
- lis r4,0xffef
- ori r4,r4,0x7403
- mtspr SPRN_TSC, r4
- li r4,0x1f4
- mtspr SPRN_TST, r4
- mfspr r4, SPRN_HID0
- ori r4, r4, 0x1
- mtspr SPRN_HID0, r4
- mfspr r4, SPRN_CTRLF
- oris r4, r4, 0x40
- mtspr SPRN_CTRLT, r4
- blr
-#endif
+ /* Not reached */
+ BUG_OPCODE
/*
* We put a few things here that have to be page-aligned.
Index: build/arch/powerpc/kernel/prom_init.c
===================================================================
--- build.orig/arch/powerpc/kernel/prom_init.c 2006-02-13 15:04:15.000000000 +1100
+++ build/arch/powerpc/kernel/prom_init.c 2006-02-13 18:08:19.000000000 +1100
@@ -205,14 +205,6 @@ static cell_t __initdata regbuf[1024];
#define MAX_CPU_THREADS 2
-/* TO GO */
-#ifdef CONFIG_HMT
-struct {
- unsigned int pir;
- unsigned int threadid;
-} hmt_thread_data[NR_CPUS];
-#endif /* CONFIG_HMT */
-
/*
* Error results ... some OF calls will return "-1" on error, some
* will return 0, some will return either. To simplify, here are
@@ -1319,10 +1311,6 @@ static void __init prom_hold_cpus(void)
*/
*spinloop = 0;
-#ifdef CONFIG_HMT
- for (i = 0; i < NR_CPUS; i++)
- RELOC(hmt_thread_data)[i].pir = 0xdeadbeef;
-#endif
/* look for cpus */
for (node = 0; prom_next_node(&node); ) {
type[0] = 0;
@@ -1389,32 +1377,6 @@ static void __init prom_hold_cpus(void)
/* Reserve cpu #s for secondary threads. They start later. */
cpuid += cpu_threads;
}
-#ifdef CONFIG_HMT
- /* Only enable HMT on processors that provide support. */
- if (__is_processor(PV_PULSAR) ||
- __is_processor(PV_ICESTAR) ||
- __is_processor(PV_SSTAR)) {
- prom_printf(" starting secondary threads\n");
-
- for (i = 0; i < NR_CPUS; i += 2) {
- if (!cpu_online(i))
- continue;
-
- if (i == 0) {
- unsigned long pir = mfspr(SPRN_PIR);
- if (__is_processor(PV_PULSAR)) {
- RELOC(hmt_thread_data)[i].pir =
- pir & 0x1f;
- } else {
- RELOC(hmt_thread_data)[i].pir =
- pir & 0x3ff;
- }
- }
- }
- } else {
- prom_printf("Processor is not HMT capable\n");
- }
-#endif
if (cpuid > NR_CPUS)
prom_printf("WARNING: maximum CPUs (" __stringify(NR_CPUS)
Index: build/arch/powerpc/platforms/pseries/Kconfig
===================================================================
--- build.orig/arch/powerpc/platforms/pseries/Kconfig 2005-11-05 20:51:08.000000000 +1100
+++ build/arch/powerpc/platforms/pseries/Kconfig 2006-02-13 18:09:21.000000000 +1100
@@ -9,13 +9,6 @@ config PPC_SPLPAR
processors, that is, which share physical processors between
two or more partitions.
-config HMT
- bool "Hardware multithreading"
- depends on SMP && PPC_PSERIES && BROKEN
- help
- This option enables hardware multithreading on RS64 cpus.
- pSeries systems p620 and p660 have such a cpu type.
-
config EEH
bool "PCI Extended Error Handling (EEH)" if EMBEDDED
depends on PPC_PSERIES
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