From: Anton Blanchard Date: Mon, 13 Feb 2006 07:11:13 +0000 (+1100) Subject: [PATCH] powerpc64: remove broken/bitrotted HMT support X-Git-Tag: v2.6.16-rc5~55^2~4 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f1870f772c5e884862b4dd8f1ec2147247dda0ef;p=linux-2.6 [PATCH] powerpc64: remove broken/bitrotted HMT support 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. Signed-off-by: Anton Blanchard Signed-off-by: Paul Mackerras --- diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index bb845eed0e..11f2cd5af7 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -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 +153,7 @@ _GLOBAL(__secondary_hold) cmpdi 0,r4,1 bne 100b -#ifdef CONFIG_HMT - SET_REG_IMMEDIATE(r4, .hmt_init) - mtctr r4 - bctr -#elif defined(CONFIG_SMP) || defined(CONFIG_KEXEC) +#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC) LOAD_REG_IMMEDIATE(r4, .pSeries_secondary_smp_init) mtctr r4 mr r3,r24 @@ -1808,22 +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 */ @@ -1937,77 +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. diff --git a/arch/powerpc/kernel/prom_init.c b/arch/powerpc/kernel/prom_init.c index ec7153f4d4..d34fe53740 100644 --- a/arch/powerpc/kernel/prom_init.c +++ b/arch/powerpc/kernel/prom_init.c @@ -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) diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig index e3fc3407bb..4e5c8f8d86 100644 --- a/arch/powerpc/platforms/pseries/Kconfig +++ b/arch/powerpc/platforms/pseries/Kconfig @@ -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