From 0d782dc430d94dc36b47cb11c2e33ecb1bb38234 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 12 Dec 2009 14:47:40 +0000 Subject: ARM: VFP: fix vfp thread init bug and document vfp notifier entry conditions When the VFP notifier is called for flush_thread(), we may be preemptible, meaning we might migrate to another CPU, which means referencing the current CPU number without some form of locking is invalid, and can cause data corruption. For the most cases, this isn't a problem since atomic notifiers are run under rcu lock, which for most configurations results in preemption being disabled - except when the preemptable tree-based rcu implementation is selected. Let's make it safe anyway. Signed-off-by: Russell King --- arch/arm/vfp/vfpmodule.c | 83 ++++++++++++++++++++++++++++++++++++------------ 1 file changed, 62 insertions(+), 21 deletions(-) (limited to 'arch') diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 2d7423af119..aed05bc3c2e 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -38,16 +38,72 @@ union vfp_state *last_VFP_context[NR_CPUS]; */ unsigned int VFP_arch; +/* + * Per-thread VFP initialization. + */ +static void vfp_thread_flush(struct thread_info *thread) +{ + union vfp_state *vfp = &thread->vfpstate; + unsigned int cpu; + + memset(vfp, 0, sizeof(union vfp_state)); + + vfp->hard.fpexc = FPEXC_EN; + vfp->hard.fpscr = FPSCR_ROUND_NEAREST; + + /* + * Disable VFP to ensure we initialize it first. We must ensure + * that the modification of last_VFP_context[] and hardware disable + * are done for the same CPU and without preemption. + */ + cpu = get_cpu(); + if (last_VFP_context[cpu] == vfp) + last_VFP_context[cpu] = NULL; + fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); + put_cpu(); +} + +static void vfp_thread_release(struct thread_info *thread) +{ + /* release case: Per-thread VFP cleanup. */ + union vfp_state *vfp = &thread->vfpstate; + unsigned int cpu = thread->cpu; + + if (last_VFP_context[cpu] == vfp) + last_VFP_context[cpu] = NULL; +} + +/* + * When this function is called with the following 'cmd's, the following + * is true while this function is being run: + * THREAD_NOFTIFY_SWTICH: + * - the previously running thread will not be scheduled onto another CPU. + * - the next thread to be run (v) will not be running on another CPU. + * - thread->cpu is the local CPU number + * - not preemptible as we're called in the middle of a thread switch + * THREAD_NOTIFY_FLUSH: + * - the thread (v) will be running on the local CPU, so + * v === current_thread_info() + * - thread->cpu is the local CPU number at the time it is accessed, + * but may change at any time. + * - we could be preempted if tree preempt rcu is enabled, so + * it is unsafe to use thread->cpu. + * THREAD_NOTIFY_RELEASE: + * - the thread (v) will not be running on any CPU; it is a dead thread. + * - thread->cpu will be the last CPU the thread ran on, which may not + * be the current CPU. + * - we could be preempted if tree preempt rcu is enabled. + */ static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v) { struct thread_info *thread = v; - union vfp_state *vfp; - __u32 cpu = thread->cpu; if (likely(cmd == THREAD_NOTIFY_SWITCH)) { u32 fpexc = fmrx(FPEXC); #ifdef CONFIG_SMP + unsigned int cpu = thread->cpu; + /* * On SMP, if VFP is enabled, save the old state in * case the thread migrates to a different CPU. The @@ -74,25 +130,10 @@ static int vfp_notifier(struct notifier_block *self, unsigned long cmd, void *v) return NOTIFY_DONE; } - vfp = &thread->vfpstate; - if (cmd == THREAD_NOTIFY_FLUSH) { - /* - * Per-thread VFP initialisation. - */ - memset(vfp, 0, sizeof(union vfp_state)); - - vfp->hard.fpexc = FPEXC_EN; - vfp->hard.fpscr = FPSCR_ROUND_NEAREST; - - /* - * Disable VFP to ensure we initialise it first. - */ - fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN); - } - - /* flush and release case: Per-thread VFP cleanup. */ - if (last_VFP_context[cpu] == vfp) - last_VFP_context[cpu] = NULL; + if (cmd == THREAD_NOTIFY_FLUSH) + vfp_thread_flush(thread); + else + vfp_thread_release(thread); return NOTIFY_DONE; } -- cgit v1.2.3 From c7baab5d1e97437a2fca63b71d467f193dbebb02 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 12 Dec 2009 14:53:08 +0000 Subject: ARM: fix clps711x, footbridge, integrator, ixp2000, ixp2300 and s3c build bug MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Anders Grafström reports that footbridge fails to build after 1c4a4f4. Fix this by adding the necessary definitions for __pfn_to_bus and __bus_to_pfn. Reported-by: Anders Grafström Signed-off-by: Russell King --- arch/arm/mach-clps711x/include/mach/memory.h | 2 ++ arch/arm/mach-footbridge/common.c | 22 +++++++++++++++++++--- arch/arm/mach-footbridge/include/mach/memory.h | 15 +++++++++------ arch/arm/mach-integrator/include/mach/memory.h | 3 ++- arch/arm/mach-ixp2000/include/mach/memory.h | 12 ++++++++---- arch/arm/mach-ixp23xx/include/mach/memory.h | 19 +++++++++---------- arch/arm/mach-s3c24a0/include/mach/memory.h | 2 ++ 7 files changed, 51 insertions(+), 24 deletions(-) (limited to 'arch') diff --git a/arch/arm/mach-clps711x/include/mach/memory.h b/arch/arm/mach-clps711x/include/mach/memory.h index e522b20bcbc..f70d52be48a 100644 --- a/arch/arm/mach-clps711x/include/mach/memory.h +++ b/arch/arm/mach-clps711x/include/mach/memory.h @@ -30,6 +30,8 @@ #define __virt_to_bus(x) ((x) - PAGE_OFFSET) #define __bus_to_virt(x) ((x) + PAGE_OFFSET) +#define __pfn_to_bus(x) (__pfn_to_phys(x) - PHYS_OFFSET) +#define __bus_to_pfn(x) __phys_to_pfn((x) + PHYS_OFFSET) #endif diff --git a/arch/arm/mach-footbridge/common.c b/arch/arm/mach-footbridge/common.c index b97f529e58e..41febc796b1 100644 --- a/arch/arm/mach-footbridge/common.c +++ b/arch/arm/mach-footbridge/common.c @@ -201,6 +201,11 @@ void __init footbridge_map_io(void) #ifdef CONFIG_FOOTBRIDGE_ADDIN +static inline unsigned long fb_bus_sdram_offset(void) +{ + return *CSR_PCISDRAMBASE & 0xfffffff0; +} + /* * These two functions convert virtual addresses to PCI addresses and PCI * addresses to virtual addresses. Note that it is only legal to use these @@ -210,14 +215,13 @@ unsigned long __virt_to_bus(unsigned long res) { WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory); - return (res - PAGE_OFFSET) + (*CSR_PCISDRAMBASE & 0xfffffff0); + return res + (fb_bus_sdram_offset() - PAGE_OFFSET); } EXPORT_SYMBOL(__virt_to_bus); unsigned long __bus_to_virt(unsigned long res) { - res -= (*CSR_PCISDRAMBASE & 0xfffffff0); - res += PAGE_OFFSET; + res = res - (fb_bus_sdram_offset() - PAGE_OFFSET); WARN_ON(res < PAGE_OFFSET || res >= (unsigned long)high_memory); @@ -225,4 +229,16 @@ unsigned long __bus_to_virt(unsigned long res) } EXPORT_SYMBOL(__bus_to_virt); +unsigned long __pfn_to_bus(unsigned long pfn) +{ + return __pfn_to_phys(pfn) + (fb_bus_sdram_offset() - PHYS_OFFSET)); +} +EXPORT_SYMBOL(__pfn_to_bus); + +unsigned long __bus_to_pfn(unsigned long bus) +{ + return __phys_to_pfn(bus - (fb_bus_sdram_offset() - PHYS_OFFSET)); +} +EXPORT_SYMBOL(__bus_to_pfn); + #endif diff --git a/arch/arm/mach-footbridge/include/mach/memory.h b/arch/arm/mach-footbridge/include/mach/memory.h index cb16e59d87b..8d64f457408 100644 --- a/arch/arm/mach-footbridge/include/mach/memory.h +++ b/arch/arm/mach-footbridge/include/mach/memory.h @@ -29,6 +29,8 @@ #ifndef __ASSEMBLY__ extern unsigned long __virt_to_bus(unsigned long); extern unsigned long __bus_to_virt(unsigned long); +extern unsigned long __pfn_to_bus(unsigned long); +extern unsigned long __bus_to_pfn(unsigned long); #endif #define __virt_to_bus __virt_to_bus #define __bus_to_virt __bus_to_virt @@ -36,14 +38,15 @@ extern unsigned long __bus_to_virt(unsigned long); #elif defined(CONFIG_FOOTBRIDGE_HOST) /* - * The footbridge is programmed to expose the system RAM at the corresponding - * address. So, if PAGE_OFFSET is 0xc0000000, RAM appears at 0xe0000000. - * If 0x80000000, then its exposed at 0xa0000000 on the bus. etc. - * The only requirement is that the RAM isn't placed at bus address 0 which + * The footbridge is programmed to expose the system RAM at 0xe0000000. + * The requirement is that the RAM isn't placed at bus address 0, which * would clash with VGA cards. */ -#define __virt_to_bus(x) ((x) - 0xe0000000) -#define __bus_to_virt(x) ((x) + 0xe0000000) +#define BUS_OFFSET 0xe0000000 +#define __virt_to_bus(x) ((x) + (BUS_OFFSET - PAGE_OFFSET)) +#define __bus_to_virt(x) ((x) - (BUS_OFFSET - PAGE_OFFSET)) +#define __pfn_to_bus(x) (__pfn_to_phys(x) + (BUS_OFFSET - PHYS_OFFSET)) +#define __bus_to_pfn(x) __phys_to_pfn((x) - (BUS_OFFSET - PHYS_OFFSET)) #else diff --git a/arch/arm/mach-integrator/include/mach/memory.h b/arch/arm/mach-integrator/include/mach/memory.h index 4891828454f..991f24d2c11 100644 --- a/arch/arm/mach-integrator/include/mach/memory.h +++ b/arch/arm/mach-integrator/include/mach/memory.h @@ -28,6 +28,7 @@ #define BUS_OFFSET UL(0x80000000) #define __virt_to_bus(x) ((x) - PAGE_OFFSET + BUS_OFFSET) #define __bus_to_virt(x) ((x) - BUS_OFFSET + PAGE_OFFSET) -#define __pfn_to_bus(x) (((x) << PAGE_SHIFT) + BUS_OFFSET) +#define __pfn_to_bus(x) (__pfn_to_phys(x) + (BUS_OFFSET - PHYS_OFFSET)) +#define __bus_to_pfn(x) __phys_to_pfn((x) - (BUS_OFFSET - PHYS_OFFSET)) #endif diff --git a/arch/arm/mach-ixp2000/include/mach/memory.h b/arch/arm/mach-ixp2000/include/mach/memory.h index aee7eb8a71b..98e3471be15 100644 --- a/arch/arm/mach-ixp2000/include/mach/memory.h +++ b/arch/arm/mach-ixp2000/include/mach/memory.h @@ -17,11 +17,15 @@ #include -#define __virt_to_bus(v) \ - (((__virt_to_phys(v) - 0x0) + (*IXP2000_PCI_SDRAM_BAR & 0xfffffff0))) +#define IXP2000_PCI_SDRAM_OFFSET (*IXP2000_PCI_SDRAM_BAR & 0xfffffff0) -#define __bus_to_virt(b) \ - __phys_to_virt((((b - (*IXP2000_PCI_SDRAM_BAR & 0xfffffff0)) + 0x0))) +#define __phys_to_bus(x) ((x) + (IXP2000_PCI_SDRAM_OFFSET - PHYS_OFFSET)) +#define __bus_to_phys(x) ((x) - (IXP2000_PCI_SDRAM_OFFSET - PHYS_OFFSET)) + +#define __virt_to_bus(v) __phys_to_bus(__virt_to_phys(v)) +#define __bus_to_virt(b) __phys_to_virt(__bus_to_phys(b)) +#define __pfn_to_bus(p) __phys_to_bus(__pfn_to_phys(p)) +#define __bus_to_pfn(b) __phys_to_pfn(__bus_to_phys(b)) #endif diff --git a/arch/arm/mach-ixp23xx/include/mach/memory.h b/arch/arm/mach-ixp23xx/include/mach/memory.h index fdd138706c7..94a3a86cfeb 100644 --- a/arch/arm/mach-ixp23xx/include/mach/memory.h +++ b/arch/arm/mach-ixp23xx/include/mach/memory.h @@ -19,16 +19,15 @@ */ #define PHYS_OFFSET (0x00000000) -#define __virt_to_bus(v) \ - ({ unsigned int ret; \ - ret = ((__virt_to_phys(v) - 0x00000000) + \ - (*((volatile int *)IXP23XX_PCI_SDRAM_BAR) & 0xfffffff0)); \ - ret; }) - -#define __bus_to_virt(b) \ - ({ unsigned int data; \ - data = *((volatile int *)IXP23XX_PCI_SDRAM_BAR); \ - __phys_to_virt((((b - (data & 0xfffffff0)) + 0x00000000))); }) +#define IXP23XX_PCI_SDRAM_OFFSET (*((volatile int *)IXP23XX_PCI_SDRAM_BAR) & 0xfffffff0)) + +#define __phys_to_bus(x) ((x) + (IXP23XX_PCI_SDRAM_OFFSET - PHYS_OFFSET)) +#define __bus_to_phys(x) ((x) - (IXP23XX_PCI_SDRAM_OFFSET - PHYS_OFFSET)) + +#define __virt_to_bus(v) __phys_to_bus(__virt_to_phys(v)) +#define __bus_to_virt(b) __phys_to_virt(__bus_to_phys(b)) +#define __pfn_to_bus(p) __phys_to_bus(__pfn_to_phys(p)) +#define __bus_to_pfn(b) __phys_to_pfn(__bus_to_phys(b)) #define arch_is_coherent() 1 diff --git a/arch/arm/mach-s3c24a0/include/mach/memory.h b/arch/arm/mach-s3c24a0/include/mach/memory.h index 585211ca018..7d74fd5c8d6 100644 --- a/arch/arm/mach-s3c24a0/include/mach/memory.h +++ b/arch/arm/mach-s3c24a0/include/mach/memory.h @@ -15,5 +15,7 @@ #define __virt_to_bus(x) __virt_to_phys(x) #define __bus_to_virt(x) __phys_to_virt(x) +#define __pfn_to_bus(x) __pfn_to_phys(x) +#define __bus_to_pfn(x) __phys_to_pfn(x) #endif -- cgit v1.2.3 From 1937f5b91833e2e8e53bcc821fc7a5fbe6ccb9b5 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 12 Dec 2009 16:20:57 +0000 Subject: ARM: fix sa1100 build Fix: arch/arm/mach-sa1100/generic.c:117: error: redefinition of 'cpufreq_get' include/linux/cpufreq.h:299: error: previous definition of 'cpufreq_get' was here cpufreq_get() is used on these platforms to tell drivers what the CPU frequency is, and therefore the bus frequency - which is critical for setting the PCMCIA and LCD timings. Adding ifdefs to these drivers to select cpufreq_get() or some other interface adds confusion. Making these drivers use some other interface for the normal paths and cpufreq stuff for the cpufreq notifier is insane as well. (Why x86 can't provide a version of cpufreq_get() which returns the CPU frequency when CPUFREQ is disabled is beyond me, rather than requiring a dummy zero-returning cpufreq_get(). Especially as they do: unsigned long khz = cpufreq_get(cpu); if (!khz) khz = tsc_khz; In other words, if CPUFREQ is disabled, get it from tsc_khz - why not provide a dummy cpufreq_get() which returns tsc_khz?) Signed-off-by: Russell King --- arch/arm/Kconfig | 5 +---- arch/arm/mach-sa1100/Kconfig | 13 +++++++++++++ arch/arm/mach-sa1100/generic.c | 12 ------------ 3 files changed, 14 insertions(+), 16 deletions(-) (limited to 'arch') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index cf8a99f19dc..233a222752c 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -603,6 +603,7 @@ config ARCH_SA1100 select ARCH_SPARSEMEM_ENABLE select ARCH_MTD_XIP select ARCH_HAS_CPUFREQ + select CPU_FREQ select GENERIC_GPIO select GENERIC_TIME select GENERIC_CLOCKEVENTS @@ -1359,13 +1360,9 @@ source "drivers/cpufreq/Kconfig" config CPU_FREQ_SA1100 bool - depends on CPU_FREQ && (SA1100_H3100 || SA1100_H3600 || SA1100_LART || SA1100_PLEB || SA1100_BADGE4 || SA1100_HACKKIT) - default y config CPU_FREQ_SA1110 bool - depends on CPU_FREQ && (SA1100_ASSABET || SA1100_CERF || SA1100_PT_SYSTEM3) - default y config CPU_FREQ_INTEGRATOR tristate "CPUfreq driver for ARM Integrator CPUs" diff --git a/arch/arm/mach-sa1100/Kconfig b/arch/arm/mach-sa1100/Kconfig index 03a7f3857c5..b17d52f7cc4 100644 --- a/arch/arm/mach-sa1100/Kconfig +++ b/arch/arm/mach-sa1100/Kconfig @@ -4,6 +4,7 @@ menu "SA11x0 Implementations" config SA1100_ASSABET bool "Assabet" + select CPU_FREQ_SA1110 help Say Y here if you are using the Intel(R) StrongARM(R) SA-1110 Microprocessor Development Board (also known as the Assabet). @@ -19,6 +20,7 @@ config ASSABET_NEPONSET config SA1100_CERF bool "CerfBoard" + select CPU_FREQ_SA1110 help The Intrinsyc CerfBoard is based on the StrongARM 1110 (Discontinued). More information is available at: @@ -45,6 +47,7 @@ endchoice config SA1100_COLLIE bool "Sharp Zaurus SL5500" + # FIXME: select CPU_FREQ_SA11x0 select SHARP_LOCOMO select SHARP_SCOOP select SHARP_PARAM @@ -54,6 +57,7 @@ config SA1100_COLLIE config SA1100_H3100 bool "Compaq iPAQ H3100" select HTC_EGPIO + select CPU_FREQ_SA1100 help Say Y here if you intend to run this kernel on the Compaq iPAQ H3100 handheld computer. Information about this machine and the @@ -64,6 +68,7 @@ config SA1100_H3100 config SA1100_H3600 bool "Compaq iPAQ H3600/H3700" select HTC_EGPIO + select CPU_FREQ_SA1100 help Say Y here if you intend to run this kernel on the Compaq iPAQ H3600 handheld computer. Information about this machine and the @@ -74,6 +79,7 @@ config SA1100_H3600 config SA1100_BADGE4 bool "HP Labs BadgePAD 4" select SA1111 + select CPU_FREQ_SA1100 help Say Y here if you want to build a kernel for the HP Laboratories BadgePAD 4. @@ -81,6 +87,7 @@ config SA1100_BADGE4 config SA1100_JORNADA720 bool "HP Jornada 720" select SA1111 + # FIXME: select CPU_FREQ_SA11x0 help Say Y here if you want to build a kernel for the HP Jornada 720 handheld computer. See @@ -98,12 +105,14 @@ config SA1100_JORNADA720_SSP config SA1100_HACKKIT bool "HackKit Core CPU Board" + select CPU_FREQ_SA1100 help Say Y here to support the HackKit Core CPU Board ; config SA1100_LART bool "LART" + select CPU_FREQ_SA1100 help Say Y here if you are using the Linux Advanced Radio Terminal (also known as the LART). See for @@ -111,6 +120,7 @@ config SA1100_LART config SA1100_PLEB bool "PLEB" + select CPU_FREQ_SA1100 help Say Y here if you are using version 1 of the Portable Linux Embedded Board (also known as PLEB). @@ -119,6 +129,7 @@ config SA1100_PLEB config SA1100_SHANNON bool "Shannon" + select CPU_FREQ_SA1100 help The Shannon (also known as a Tuxscreen, and also as a IS2630) was a limited edition webphone produced by Philips. The Shannon is a SA1100 @@ -127,6 +138,7 @@ config SA1100_SHANNON config SA1100_SIMPAD bool "Simpad" + select CPU_FREQ_SA1110 help The SIEMENS webpad SIMpad is based on the StrongARM 1110. There are two different versions CL4 and SL4. CL4 has 32MB RAM and 16MB @@ -145,3 +157,4 @@ config SA1100_SSP endmenu endif + diff --git a/arch/arm/mach-sa1100/generic.c b/arch/arm/mach-sa1100/generic.c index 9faea1511c1..3c1fcd69671 100644 --- a/arch/arm/mach-sa1100/generic.c +++ b/arch/arm/mach-sa1100/generic.c @@ -58,7 +58,6 @@ static const unsigned short cclk_frequency_100khz[NR_FREQS] = { 2802 /* 280.2 MHz */ }; -#if defined(CONFIG_CPU_FREQ_SA1100) || defined(CONFIG_CPU_FREQ_SA1110) /* rounds up(!) */ unsigned int sa11x0_freq_to_ppcr(unsigned int khz) { @@ -110,17 +109,6 @@ unsigned int sa11x0_getspeed(unsigned int cpu) return cclk_frequency_100khz[PPCR & 0xf] * 100; } -#else -/* - * We still need to provide this so building without cpufreq works. - */ -unsigned int cpufreq_get(unsigned int cpu) -{ - return cclk_frequency_100khz[PPCR & 0xf] * 100; -} -EXPORT_SYMBOL(cpufreq_get); -#endif - /* * This is the SA11x0 sched_clock implementation. This has * a resolution of 271ns, and a maximum value of 32025597s (370 days). -- cgit v1.2.3 From 9074e144c10cba5d6bb6b326a8be5347d38e4473 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 12 Dec 2009 16:27:25 +0000 Subject: ARM: fix lh7a40x build No idea if this platform actually uses cpufreq_get(), but it doesn't have any cpufreq drivers. That's not to say it doesn't use cpufreq_get() in its drivers. LH7a40x is unmaintained anyhow, and should probably be killed off. Signed-off-by: Russell King --- arch/arm/mach-lh7a40x/clocks.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'arch') diff --git a/arch/arm/mach-lh7a40x/clocks.c b/arch/arm/mach-lh7a40x/clocks.c index 6182f5410b4..fcaf876f19b 100644 --- a/arch/arm/mach-lh7a40x/clocks.c +++ b/arch/arm/mach-lh7a40x/clocks.c @@ -7,8 +7,6 @@ * version 2 as published by the Free Software Foundation. * */ - -#include #include #include #include @@ -31,12 +29,6 @@ struct clk { #define HCLKDIV(c) (((c) >> 0) & 0x02) #define PCLKDIV(c) (((c) >> 16) & 0x03) -unsigned int cpufreq_get (unsigned int cpu) /* in kHz */ -{ - return fclkfreq_get ()/1000; -} -EXPORT_SYMBOL(cpufreq_get); - unsigned int fclkfreq_get (void) { unsigned int clkset = CSC_CLKSET; -- cgit v1.2.3