From c2f07fe64dc0da6d4ccc02d858695356bd685aeb Mon Sep 17 00:00:00 2001 From: Sebastian Hesselbarth Date: Thu, 24 Apr 2014 22:54:58 +0100 Subject: ARM: 8038/1: iwmmxt: explicitly check for supported architectures iwmmxt.S requires special treatment of coprocessor access registers for PJ4 and XScale-based CPUs. It only checks for CPU_PJ4 and drops down to XScale-based treatment on all other architectures. As some PJ4B also come with iWMMXt and also need PJ4 treatment, rework the corresponding preprocessor directives to explicitly check for supported architectures and fail on unsupported ones. Signed-off-by: Sebastian Hesselbarth Tested-by: Thomas Petazzoni Tested-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/kernel/iwmmxt.S | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/iwmmxt.S b/arch/arm/kernel/iwmmxt.S index a08783823b32..2452dd1bef53 100644 --- a/arch/arm/kernel/iwmmxt.S +++ b/arch/arm/kernel/iwmmxt.S @@ -19,12 +19,16 @@ #include #include -#if defined(CONFIG_CPU_PJ4) +#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B) #define PJ4(code...) code #define XSC(code...) -#else +#elif defined(CONFIG_CPU_MOHAWK) || \ + defined(CONFIG_CPU_XSC3) || \ + defined(CONFIG_CPU_XSCALE) #define PJ4(code...) #define XSC(code...) code +#else +#error "Unsupported iWMMXt architecture" #endif #define MMX_WR0 (0x00) -- cgit v1.2.1 From 7d0656598924b2781fb96cdff566c9f844643fcd Mon Sep 17 00:00:00 2001 From: Sebastian Hesselbarth Date: Thu, 24 Apr 2014 22:56:43 +0100 Subject: ARM: 8039/1: pj4: enable iWMMXt only if CONFIG_IWMMXT is set This fixes PJ4 coprocessor init to only expose iWMMXt capabilities, if the corresponding kernel support for iWMMXt is enabled. Signed-off-by: Sebastian Hesselbarth Tested-by: Thomas Petazzoni Tested-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/kernel/pj4-cp0.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/pj4-cp0.c b/arch/arm/kernel/pj4-cp0.c index fc7208636284..12352cd30ab2 100644 --- a/arch/arm/kernel/pj4-cp0.c +++ b/arch/arm/kernel/pj4-cp0.c @@ -45,7 +45,7 @@ static int iwmmxt_do(struct notifier_block *self, unsigned long cmd, void *t) return NOTIFY_DONE; } -static struct notifier_block iwmmxt_notifier_block = { +static struct notifier_block __maybe_unused iwmmxt_notifier_block = { .notifier_call = iwmmxt_do, }; @@ -79,17 +79,21 @@ static void __init pj4_cp_access_write(u32 value) */ static int __init pj4_cp0_init(void) { - u32 cp_access; + u32 __maybe_unused cp_access; if (!cpu_is_pj4()) return 0; +#ifndef CONFIG_IWMMXT + pr_info("PJ4 iWMMXt coprocessor detected, but kernel support is missing.\n"); +#else cp_access = pj4_cp_access_read() & ~0xf; pj4_cp_access_write(cp_access); printk(KERN_INFO "PJ4 iWMMXt coprocessor enabled.\n"); elf_hwcap |= HWCAP_IWMMXT; thread_register_notifier(&iwmmxt_notifier_block); +#endif return 0; } -- cgit v1.2.1 From e89f443b182c7a813a60d85dbf22d090231b5e6b Mon Sep 17 00:00:00 2001 From: Sebastian Hesselbarth Date: Thu, 24 Apr 2014 22:57:25 +0100 Subject: ARM: 8040/1: pj4: properly detect existence of iWMMXt coprocessor commit fdb487f5c961b94486a78fa61fa28b8eff1954ab ("ARM: 8015/1: Add cpu_is_pj4 to distinguish PJ4 because it has some differences with V7") introduced a fix for checking PJ4 cpuid to not use PJ4 specific coprocessor access on non-PJ4 platforms. Unfortunately, this in turn broke Marvell Armada 370/XP, both comprising Marvell PJ4B CPUs without iWMMXt extension. Instead of only checking for cpuid, which may not be sufficient to determine iWMMXt support, the presence of iWMMXt coprocessors can be checked by enabling and reading the Coprocessor ID register (wCID, register 0 of CP1). Therefore this adds an explicit check for the presence and correct wCID value, before enabling iWMMXt capabilities. As a bonus, also print the iWMMXt version of a detected coprocessor. This has been tested to properly detect iWMMXt presence/absence on: - PJ4, CPUID 0x560f5815, wCID 0x56052001: Marvell Dove, iWMMXt v2 - PJ4B, CPUID 0x561f5811: Marvell Armada 370, no iWMMXt - PJ4B, CPUID 0x562f5841, wCID 0x56052001: Marvell Armada 1500, iWMMXt v2 - PJ4B, CPUID 0x562f5842: Marvell Armada XP, no iWMMXt Signed-off-by: Sebastian Hesselbarth Tested-by: Thomas Petazzoni Tested-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/kernel/pj4-cp0.c | 34 +++++++++++++++++++++++++++++++++- 1 file changed, 33 insertions(+), 1 deletion(-) (limited to 'arch/arm') diff --git a/arch/arm/kernel/pj4-cp0.c b/arch/arm/kernel/pj4-cp0.c index 12352cd30ab2..8153e36b2491 100644 --- a/arch/arm/kernel/pj4-cp0.c +++ b/arch/arm/kernel/pj4-cp0.c @@ -72,6 +72,33 @@ static void __init pj4_cp_access_write(u32 value) : "=r" (temp) : "r" (value)); } +static int __init pj4_get_iwmmxt_version(void) +{ + u32 cp_access, wcid; + + cp_access = pj4_cp_access_read(); + pj4_cp_access_write(cp_access | 0xf); + + /* check if coprocessor 0 and 1 are available */ + if ((pj4_cp_access_read() & 0xf) != 0xf) { + pj4_cp_access_write(cp_access); + return -ENODEV; + } + + /* read iWMMXt coprocessor id register p1, c0 */ + __asm__ __volatile__ ("mrc p1, 0, %0, c0, c0, 0\n" : "=r" (wcid)); + + pj4_cp_access_write(cp_access); + + /* iWMMXt v1 */ + if ((wcid & 0xffffff00) == 0x56051000) + return 1; + /* iWMMXt v2 */ + if ((wcid & 0xffffff00) == 0x56052000) + return 2; + + return -EINVAL; +} /* * Disable CP0/CP1 on boot, and let call_fpe() and the iWMMXt lazy @@ -80,17 +107,22 @@ static void __init pj4_cp_access_write(u32 value) static int __init pj4_cp0_init(void) { u32 __maybe_unused cp_access; + int vers; if (!cpu_is_pj4()) return 0; + vers = pj4_get_iwmmxt_version(); + if (vers < 0) + return 0; + #ifndef CONFIG_IWMMXT pr_info("PJ4 iWMMXt coprocessor detected, but kernel support is missing.\n"); #else cp_access = pj4_cp_access_read() & ~0xf; pj4_cp_access_write(cp_access); - printk(KERN_INFO "PJ4 iWMMXt coprocessor enabled.\n"); + pr_info("PJ4 iWMMXt v%d coprocessor enabled.\n", vers); elf_hwcap |= HWCAP_IWMMXT; thread_register_notifier(&iwmmxt_notifier_block); #endif -- cgit v1.2.1 From cd1711709fe98d3569e7f8215ba31adcfc3686ae Mon Sep 17 00:00:00 2001 From: Sebastian Hesselbarth Date: Thu, 24 Apr 2014 22:58:00 +0100 Subject: ARM: 8041/1: pj4: fix cpu_is_pj4 check Commit fdb487f5c961b94486a78fa61fa28b8eff1954ab ("ARM: 8015/1: Add cpu_is_pj4 to distinguish PJ4 because it has some differences with V7") introduced a cpuid check for Marvell PJ4 processors to fix a regression caused by adding PJ4 based Marvell Dove into multi_v7. Unfortunately, this check is too narrow to catch PJ4 used on Dove itself and breaks iWMMXt support. This patch therefore relaxes the cpuid mask to match both PJ4 and PJ4B. Also, rework the given comment about PJ4/PJ4B modifications to be a little bit more specific about the differences. Signed-off-by: Sebastian Hesselbarth Tested-by: Thomas Petazzoni Tested-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/include/asm/cputype.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h index c651e3b26ec7..4764344367d4 100644 --- a/arch/arm/include/asm/cputype.h +++ b/arch/arm/include/asm/cputype.h @@ -222,22 +222,22 @@ static inline int cpu_is_xsc3(void) #endif /* - * Marvell's PJ4 core is based on V7 version. It has some modification - * for coprocessor setting. For this reason, we need a way to distinguish - * it. + * Marvell's PJ4 and PJ4B cores are based on V7 version, + * but require a specical sequence for enabling coprocessors. + * For this reason, we need a way to distinguish them. */ -#ifndef CONFIG_CPU_PJ4 -#define cpu_is_pj4() 0 -#else +#if defined(CONFIG_CPU_PJ4) || defined(CONFIG_CPU_PJ4B) static inline int cpu_is_pj4(void) { unsigned int id; id = read_cpuid_id(); - if ((id & 0xfffffff0) == 0x562f5840) + if ((id & 0xff0fff00) == 0x560f5800) return 1; return 0; } +#else +#define cpu_is_pj4() 0 #endif #endif -- cgit v1.2.1 From d93003e8e4e1fbbc8a06ec561a63f5aa105a4c45 Mon Sep 17 00:00:00 2001 From: Sebastian Hesselbarth Date: Thu, 24 Apr 2014 22:58:30 +0100 Subject: ARM: 8042/1: iwmmxt: allow to build iWMMXt on Marvell PJ4B Some Marvell PJ4B CPUs also implement iWMMXt extensions. With a proper check for iWMMXt coprocessors now in place, enable it by default on PJ4B. While at it, also allow to manually select the corresponding Kconfig option. Signed-off-by: Sebastian Hesselbarth Tested-by: Thomas Petazzoni Tested-by: Kevin Hilman Signed-off-by: Russell King --- arch/arm/Kconfig | 6 +++--- arch/arm/kernel/Makefile | 1 + 2 files changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 53e99eb543d9..767a1aa4a360 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1110,9 +1110,9 @@ config ARM_NR_BANKS default 8 config IWMMXT - bool "Enable iWMMXt support" if !CPU_PJ4 - depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 - default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 + bool "Enable iWMMXt support" + depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B + default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B help Enable support for iWMMXt context switching at run time if running on a CPU that supports it. diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index a766bcbaf8ad..040619c32d68 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -79,6 +79,7 @@ obj-$(CONFIG_CPU_XSCALE) += xscale-cp0.o obj-$(CONFIG_CPU_XSC3) += xscale-cp0.o obj-$(CONFIG_CPU_MOHAWK) += xscale-cp0.o obj-$(CONFIG_CPU_PJ4) += pj4-cp0.o +obj-$(CONFIG_CPU_PJ4B) += pj4-cp0.o obj-$(CONFIG_IWMMXT) += iwmmxt.o obj-$(CONFIG_PERF_EVENTS) += perf_regs.o obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o perf_event_cpu.o -- cgit v1.2.1