[PATCH] ppc64: make firmware_has_feature() stronger

Make firmware_has_feature() evaluate at compile time for the non pSeries
case and tidy up code where possible.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/ppc64/kernel/Makefile

@@ -11,7 +11,7 @@ obj-y               :=	setup.o entry.o traps.o irq.o idle.o dma.o \
 			udbg.o binfmt_elf32.o sys_ppc32.o ioctl32.o \
 			ptrace32.o signal32.o rtc.o init_task.o \
 			lmb.o cputable.o cpu_setup_power4.o idle_power4.o \
-			iommu.o sysfs.o vdso.o pmc.o
+			iommu.o sysfs.o vdso.o pmc.o firmware.o
 obj-y += vdso32/ vdso64/
 
 obj-$(CONFIG_PPC_OF) +=	of_device.o

arch/ppc64/kernel/cputable.c

@@ -20,11 +20,9 @@
 #include <linux/module.h>
 
 #include <asm/cputable.h>
-#include <asm/firmware.h>
 
 struct cpu_spec* cur_cpu_spec = NULL;
 EXPORT_SYMBOL(cur_cpu_spec);
-unsigned long ppc64_firmware_features;
 
 /* NOTE:
  * Unlike ppc32, ppc64 will only call this once for the boot CPU, it's
@@ -244,26 +242,3 @@ struct cpu_spec	cpu_specs[] = {
 		.cpu_setup		= __setup_cpu_power4,
 	}
 };
-
-firmware_feature_t firmware_features_table[FIRMWARE_MAX_FEATURES] = {
-	{FW_FEATURE_PFT,		"hcall-pft"},
-	{FW_FEATURE_TCE,		"hcall-tce"},
-	{FW_FEATURE_SPRG0,		"hcall-sprg0"},
-	{FW_FEATURE_DABR,		"hcall-dabr"},
-	{FW_FEATURE_COPY,		"hcall-copy"},
-	{FW_FEATURE_ASR,		"hcall-asr"},
-	{FW_FEATURE_DEBUG,		"hcall-debug"},
-	{FW_FEATURE_PERF,		"hcall-perf"},
-	{FW_FEATURE_DUMP,		"hcall-dump"},
-	{FW_FEATURE_INTERRUPT,		"hcall-interrupt"},
-	{FW_FEATURE_MIGRATE,		"hcall-migrate"},
-	{FW_FEATURE_PERFMON,		"hcall-perfmon"},
-	{FW_FEATURE_CRQ,		"hcall-crq"},
-	{FW_FEATURE_VIO,		"hcall-vio"},
-	{FW_FEATURE_RDMA,		"hcall-rdma"},
-	{FW_FEATURE_LLAN,		"hcall-lLAN"},
-	{FW_FEATURE_BULK,		"hcall-bulk"},
-	{FW_FEATURE_XDABR,		"hcall-xdabr"},
-	{FW_FEATURE_MULTITCE,		"hcall-multi-tce"},
-	{FW_FEATURE_SPLPAR,		"hcall-splpar"},
-};

arch/ppc64/kernel/firmware.c

+/*
+ *  arch/ppc64/kernel/firmware.c
+ *
+ *  Extracted from cputable.c
+ *
+ *  Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
+ *
+ *  Modifications for ppc64:
+ *      Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
+ *  Copyright (C) 2005 Stephen Rothwell, IBM Corporation
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+
+#include <asm/firmware.h>
+
+unsigned long ppc64_firmware_features;
+
+#ifdef CONFIG_PPC_PSERIES
+firmware_feature_t firmware_features_table[FIRMWARE_MAX_FEATURES] = {
+	{FW_FEATURE_PFT,		"hcall-pft"},
+	{FW_FEATURE_TCE,		"hcall-tce"},
+	{FW_FEATURE_SPRG0,		"hcall-sprg0"},
+	{FW_FEATURE_DABR,		"hcall-dabr"},
+	{FW_FEATURE_COPY,		"hcall-copy"},
+	{FW_FEATURE_ASR,		"hcall-asr"},
+	{FW_FEATURE_DEBUG,		"hcall-debug"},
+	{FW_FEATURE_PERF,		"hcall-perf"},
+	{FW_FEATURE_DUMP,		"hcall-dump"},
+	{FW_FEATURE_INTERRUPT,		"hcall-interrupt"},
+	{FW_FEATURE_MIGRATE,		"hcall-migrate"},
+	{FW_FEATURE_PERFMON,		"hcall-perfmon"},
+	{FW_FEATURE_CRQ,		"hcall-crq"},
+	{FW_FEATURE_VIO,		"hcall-vio"},
+	{FW_FEATURE_RDMA,		"hcall-rdma"},
+	{FW_FEATURE_LLAN,		"hcall-lLAN"},
+	{FW_FEATURE_BULK,		"hcall-bulk"},
+	{FW_FEATURE_XDABR,		"hcall-xdabr"},
+	{FW_FEATURE_MULTITCE,		"hcall-multi-tce"},
+	{FW_FEATURE_SPLPAR,		"hcall-splpar"},
+};
+#endif

arch/ppc64/kernel/pSeries_setup.c

@@ -231,11 +231,9 @@ static void __init pSeries_setup_arch(void)
 
 	pSeries_nvram_init();
 
-	if (firmware_has_feature(FW_FEATURE_SPLPAR))
-		vpa_init(boot_cpuid);
-
 	/* Choose an idle loop */
 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+		vpa_init(boot_cpuid);
 		if (get_paca()->lppaca.shared_proc) {
 			printk(KERN_INFO "Using shared processor idle loop\n");
 			ppc_md.idle_loop = pseries_shared_idle;

arch/ppc64/kernel/process.c

@@ -203,10 +203,9 @@ struct task_struct *__switch_to(struct task_struct *prev,
 	new_thread = &new->thread;
 	old_thread = &current->thread;
 
-/* Collect purr utilization data per process and per processor wise */
-/* purr is nothing but processor time base                          */
-
-#if defined(CONFIG_PPC_PSERIES)
+	/* Collect purr utilization data per process and per processor
+	 * wise purr is nothing but processor time base
+	 */
 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
 		struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
 		long unsigned start_tb, current_tb;
@@ -215,8 +214,6 @@ struct task_struct *__switch_to(struct task_struct *prev,
 		old_thread->accum_tb += (current_tb - start_tb);
 		new_thread->start_tb = current_tb;
 	}
-#endif
-
 
 	local_irq_save(flags);
 	last = _switch(old_thread, new_thread);

arch/ppc64/kernel/sysfs.c

@@ -153,11 +153,9 @@ void ppc64_enable_pmcs(void)
 		break;
 	}
 
-#ifdef CONFIG_PPC_PSERIES
 	/* instruct hypervisor to maintain PMCs */
 	if (firmware_has_feature(FW_FEATURE_SPLPAR))
 		get_paca()->lppaca.pmcregs_in_use = 1;
-#endif /* CONFIG_PPC_PSERIES */
 }
 
 #else

arch/ppc64/kernel/time.c

@@ -371,13 +371,11 @@ int timer_interrupt(struct pt_regs * regs)
 		process_hvlpevents(regs);
 #endif
 
-/* collect purr register values often, for accurate calculations */
-#if defined(CONFIG_PPC_PSERIES)
+	/* collect purr register values often, for accurate calculations */
 	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
 		struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
 		cu->current_tb = mfspr(SPRN_PURR);
 	}
-#endif
 
 	irq_exit();
 

include/asm-ppc64/firmware.h

@@ -45,6 +45,22 @@
 #define FW_FEATURE_MULTITCE	(1UL<<19)
 #define FW_FEATURE_SPLPAR	(1UL<<20)
 
+enum {
+	FW_FEATURE_PSERIES = FW_FEATURE_PFT | FW_FEATURE_TCE |
+		FW_FEATURE_SPRG0 | FW_FEATURE_DABR | FW_FEATURE_COPY |
+		FW_FEATURE_ASR | FW_FEATURE_DEBUG | FW_FEATURE_TERM |
+		FW_FEATURE_PERF | FW_FEATURE_DUMP | FW_FEATURE_INTERRUPT |
+		FW_FEATURE_MIGRATE | FW_FEATURE_PERFMON | FW_FEATURE_CRQ |
+		FW_FEATURE_VIO | FW_FEATURE_RDMA | FW_FEATURE_LLAN |
+		FW_FEATURE_BULK | FW_FEATURE_XDABR | FW_FEATURE_MULTITCE |
+		FW_FEATURE_SPLPAR,
+	FW_FEATURE_POSSIBLE =
+#ifdef CONFIG_PPC_PSERIES
+		FW_FEATURE_PSERIES |
+#endif
+		0,
+};
+
 /* This is used to identify firmware features which are available
  * to the kernel.
  */
@@ -52,15 +68,17 @@ extern unsigned long	ppc64_firmware_features;
 
 static inline unsigned long firmware_has_feature(unsigned long feature)
 {
-	return ppc64_firmware_features & feature;
+	return ppc64_firmware_features & feature & FW_FEATURE_POSSIBLE;
 }
 
+#ifdef CONFIG_PPC_PSERIES
 typedef struct {
     unsigned long val;
     char * name;
 } firmware_feature_t;
 
 extern firmware_feature_t firmware_features_table[];
+#endif
 
 #endif /* __ASSEMBLY__ */
 #endif /* __KERNEL__ */