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Merge master.kernel.org:/home/rmk/linux-2.6-arm

* master.kernel.org:/home/rmk/linux-2.6-arm:
  ARM: 5974/1: arm/mach-at91 Makefile: remove two blanks.
  ARM: 6052/1: kdump: make kexec work in interrupt context
  ARM: 6051/1: VFP: preserve the HW context when calling signal handlers
  ARM: 6050/1: VFP: fix the SMP versions of vfp_{sync,flush}_hwstate
  ARM: 6007/1: fix highmem with VIPT cache and DMA
  ARM: 5975/1: AT91 slow-clock suspend: don't wait when turning PLLs off
Linus Torvalds 15 år sedan
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eb3e5cce2b

+ 14 - 1
arch/arm/include/asm/highmem.h

@@ -11,7 +11,11 @@
 
 #define kmap_prot		PAGE_KERNEL
 
-#define flush_cache_kmaps()	flush_cache_all()
+#define flush_cache_kmaps() \
+	do { \
+		if (cache_is_vivt()) \
+			flush_cache_all(); \
+	} while (0)
 
 extern pte_t *pkmap_page_table;
 
@@ -21,11 +25,20 @@ extern void *kmap_high(struct page *page);
 extern void *kmap_high_get(struct page *page);
 extern void kunmap_high(struct page *page);
 
+extern void *kmap_high_l1_vipt(struct page *page, pte_t *saved_pte);
+extern void kunmap_high_l1_vipt(struct page *page, pte_t saved_pte);
+
+/*
+ * The following functions are already defined by <linux/highmem.h>
+ * when CONFIG_HIGHMEM is not set.
+ */
+#ifdef CONFIG_HIGHMEM
 extern void *kmap(struct page *page);
 extern void kunmap(struct page *page);
 extern void *kmap_atomic(struct page *page, enum km_type type);
 extern void kunmap_atomic(void *kvaddr, enum km_type type);
 extern void *kmap_atomic_pfn(unsigned long pfn, enum km_type type);
 extern struct page *kmap_atomic_to_page(const void *ptr);
+#endif
 
 #endif

+ 1 - 0
arch/arm/include/asm/kmap_types.h

@@ -18,6 +18,7 @@ enum km_type {
 	KM_IRQ1,
 	KM_SOFTIRQ0,
 	KM_SOFTIRQ1,
+	KM_L1_CACHE,
 	KM_L2_CACHE,
 	KM_TYPE_NR
 };

+ 11 - 12
arch/arm/include/asm/ucontext.h

@@ -59,23 +59,22 @@ struct iwmmxt_sigframe {
 #endif /* CONFIG_IWMMXT */
 
 #ifdef CONFIG_VFP
-#if __LINUX_ARM_ARCH__ < 6
-/* For ARM pre-v6, we use fstmiax and fldmiax.  This adds one extra
- * word after the registers, and a word of padding at the end for
- * alignment.  */
 #define VFP_MAGIC		0x56465001
-#define VFP_STORAGE_SIZE	152
-#else
-#define VFP_MAGIC		0x56465002
-#define VFP_STORAGE_SIZE	144
-#endif
 
 struct vfp_sigframe
 {
 	unsigned long		magic;
 	unsigned long		size;
-	union vfp_state		storage;
-};
+	struct user_vfp		ufp;
+	struct user_vfp_exc	ufp_exc;
+} __attribute__((__aligned__(8)));
+
+/*
+ *  8 byte for magic and size, 264 byte for ufp, 12 bytes for ufp_exc,
+ *  4 bytes padding.
+ */
+#define VFP_STORAGE_SIZE	sizeof(struct vfp_sigframe)
+
 #endif /* CONFIG_VFP */
 
 /*
@@ -91,7 +90,7 @@ struct aux_sigframe {
 #ifdef CONFIG_IWMMXT
 	struct iwmmxt_sigframe	iwmmxt;
 #endif
-#if 0 && defined CONFIG_VFP /* Not yet saved.  */
+#ifdef CONFIG_VFP
 	struct vfp_sigframe	vfp;
 #endif
 	/* Something that isn't a valid magic number for any coprocessor.  */

+ 11 - 1
arch/arm/include/asm/user.h

@@ -83,11 +83,21 @@ struct user{
 
 /*
  * User specific VFP registers. If only VFPv2 is present, registers 16 to 31
- * are ignored by the ptrace system call.
+ * are ignored by the ptrace system call and the signal handler.
  */
 struct user_vfp {
 	unsigned long long fpregs[32];
 	unsigned long fpscr;
 };
 
+/*
+ * VFP exception registers exposed to user space during signal delivery.
+ * Fields not relavant to the current VFP architecture are ignored.
+ */
+struct user_vfp_exc {
+	unsigned long	fpexc;
+	unsigned long	fpinst;
+	unsigned long	fpinst2;
+};
+
 #endif /* _ARM_USER_H */

+ 89 - 4
arch/arm/kernel/signal.c

@@ -18,6 +18,7 @@
 #include <asm/cacheflush.h>
 #include <asm/ucontext.h>
 #include <asm/unistd.h>
+#include <asm/vfp.h>
 
 #include "ptrace.h"
 #include "signal.h"
@@ -175,6 +176,90 @@ static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame)
 
 #endif
 
+#ifdef CONFIG_VFP
+
+static int preserve_vfp_context(struct vfp_sigframe __user *frame)
+{
+	struct thread_info *thread = current_thread_info();
+	struct vfp_hard_struct *h = &thread->vfpstate.hard;
+	const unsigned long magic = VFP_MAGIC;
+	const unsigned long size = VFP_STORAGE_SIZE;
+	int err = 0;
+
+	vfp_sync_hwstate(thread);
+	__put_user_error(magic, &frame->magic, err);
+	__put_user_error(size, &frame->size, err);
+
+	/*
+	 * Copy the floating point registers. There can be unused
+	 * registers see asm/hwcap.h for details.
+	 */
+	err |= __copy_to_user(&frame->ufp.fpregs, &h->fpregs,
+			      sizeof(h->fpregs));
+	/*
+	 * Copy the status and control register.
+	 */
+	__put_user_error(h->fpscr, &frame->ufp.fpscr, err);
+
+	/*
+	 * Copy the exception registers.
+	 */
+	__put_user_error(h->fpexc, &frame->ufp_exc.fpexc, err);
+	__put_user_error(h->fpinst, &frame->ufp_exc.fpinst, err);
+	__put_user_error(h->fpinst2, &frame->ufp_exc.fpinst2, err);
+
+	return err ? -EFAULT : 0;
+}
+
+static int restore_vfp_context(struct vfp_sigframe __user *frame)
+{
+	struct thread_info *thread = current_thread_info();
+	struct vfp_hard_struct *h = &thread->vfpstate.hard;
+	unsigned long magic;
+	unsigned long size;
+	unsigned long fpexc;
+	int err = 0;
+
+	__get_user_error(magic, &frame->magic, err);
+	__get_user_error(size, &frame->size, err);
+
+	if (err)
+		return -EFAULT;
+	if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE)
+		return -EINVAL;
+
+	/*
+	 * Copy the floating point registers. There can be unused
+	 * registers see asm/hwcap.h for details.
+	 */
+	err |= __copy_from_user(&h->fpregs, &frame->ufp.fpregs,
+				sizeof(h->fpregs));
+	/*
+	 * Copy the status and control register.
+	 */
+	__get_user_error(h->fpscr, &frame->ufp.fpscr, err);
+
+	/*
+	 * Sanitise and restore the exception registers.
+	 */
+	__get_user_error(fpexc, &frame->ufp_exc.fpexc, err);
+	/* Ensure the VFP is enabled. */
+	fpexc |= FPEXC_EN;
+	/* Ensure FPINST2 is invalid and the exception flag is cleared. */
+	fpexc &= ~(FPEXC_EX | FPEXC_FP2V);
+	h->fpexc = fpexc;
+
+	__get_user_error(h->fpinst, &frame->ufp_exc.fpinst, err);
+	__get_user_error(h->fpinst2, &frame->ufp_exc.fpinst2, err);
+
+	if (!err)
+		vfp_flush_hwstate(thread);
+
+	return err ? -EFAULT : 0;
+}
+
+#endif
+
 /*
  * Do a signal return; undo the signal stack.  These are aligned to 64-bit.
  */
@@ -233,8 +318,8 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
 		err |= restore_iwmmxt_context(&aux->iwmmxt);
 #endif
 #ifdef CONFIG_VFP
-//	if (err == 0)
-//		err |= vfp_restore_state(&sf->aux.vfp);
+	if (err == 0)
+		err |= restore_vfp_context(&aux->vfp);
 #endif
 
 	return err;
@@ -348,8 +433,8 @@ setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set)
 		err |= preserve_iwmmxt_context(&aux->iwmmxt);
 #endif
 #ifdef CONFIG_VFP
-//	if (err == 0)
-//		err |= vfp_save_state(&sf->aux.vfp);
+	if (err == 0)
+		err |= preserve_vfp_context(&aux->vfp);
 #endif
 	__put_user_error(0, &aux->end_magic, err);
 

+ 2 - 2
arch/arm/mach-at91/Makefile

@@ -16,8 +16,8 @@ obj-$(CONFIG_ARCH_AT91SAM9261)	+= at91sam9261.o at91sam926x_time.o at91sam9261_d
 obj-$(CONFIG_ARCH_AT91SAM9G10)	+= at91sam9261.o at91sam926x_time.o at91sam9261_devices.o sam9_smc.o
 obj-$(CONFIG_ARCH_AT91SAM9263)	+= at91sam9263.o at91sam926x_time.o at91sam9263_devices.o sam9_smc.o
 obj-$(CONFIG_ARCH_AT91SAM9RL)	+= at91sam9rl.o at91sam926x_time.o at91sam9rl_devices.o sam9_smc.o
-obj-$(CONFIG_ARCH_AT91SAM9G20)	+= at91sam9260.o at91sam926x_time.o at91sam9260_devices.o  sam9_smc.o
- obj-$(CONFIG_ARCH_AT91SAM9G45)	+= at91sam9g45.o at91sam926x_time.o at91sam9g45_devices.o sam9_smc.o
+obj-$(CONFIG_ARCH_AT91SAM9G20)	+= at91sam9260.o at91sam926x_time.o at91sam9260_devices.o sam9_smc.o
+obj-$(CONFIG_ARCH_AT91SAM9G45)	+= at91sam9g45.o at91sam926x_time.o at91sam9g45_devices.o sam9_smc.o
 obj-$(CONFIG_ARCH_AT91CAP9)	+= at91cap9.o at91sam926x_time.o at91cap9_devices.o sam9_smc.o
 obj-$(CONFIG_ARCH_AT572D940HF)  += at572d940hf.o at91sam926x_time.o at572d940hf_devices.o sam9_smc.o
 obj-$(CONFIG_ARCH_AT91X40)	+= at91x40.o at91x40_time.o

+ 0 - 4
arch/arm/mach-at91/pm_slowclock.S

@@ -175,8 +175,6 @@ ENTRY(at91_slow_clock)
 	orr	r3, r3, #(1 << 29)		/* bit 29 always set */
 	str	r3, [r1, #(AT91_CKGR_PLLAR - AT91_PMC)]
 
-	wait_pllalock
-
 	/* Save PLLB setting and disable it */
 	ldr	r3, [r1, #(AT91_CKGR_PLLBR - AT91_PMC)]
 	str	r3, .saved_pllbr
@@ -184,8 +182,6 @@ ENTRY(at91_slow_clock)
 	mov	r3, #AT91_PMC_PLLCOUNT
 	str	r3, [r1, #(AT91_CKGR_PLLBR - AT91_PMC)]
 
-	wait_pllblock
-
 	/* Turn off the main oscillator */
 	ldr	r3, [r1, #(AT91_CKGR_MOR - AT91_PMC)]
 	bic	r3, r3, #AT91_PMC_MOSCEN

+ 1 - 8
arch/arm/mm/copypage-v6.c

@@ -41,14 +41,7 @@ static void v6_copy_user_highpage_nonaliasing(struct page *to,
 	kfrom = kmap_atomic(from, KM_USER0);
 	kto = kmap_atomic(to, KM_USER1);
 	copy_page(kto, kfrom);
-#ifdef CONFIG_HIGHMEM
-	/*
-	 * kmap_atomic() doesn't set the page virtual address, and
-	 * kunmap_atomic() takes care of cache flushing already.
-	 */
-	if (page_address(to) != NULL)
-#endif
-		__cpuc_flush_dcache_area(kto, PAGE_SIZE);
+	__cpuc_flush_dcache_area(kto, PAGE_SIZE);
 	kunmap_atomic(kto, KM_USER1);
 	kunmap_atomic(kfrom, KM_USER0);
 }

+ 5 - 0
arch/arm/mm/dma-mapping.c

@@ -464,6 +464,11 @@ static void dma_cache_maint_page(struct page *page, unsigned long offset,
 				vaddr += offset;
 				op(vaddr, len, dir);
 				kunmap_high(page);
+			} else if (cache_is_vipt()) {
+				pte_t saved_pte;
+				vaddr = kmap_high_l1_vipt(page, &saved_pte);
+				op(vaddr + offset, len, dir);
+				kunmap_high_l1_vipt(page, saved_pte);
 			}
 		} else {
 			vaddr = page_address(page) + offset;

+ 15 - 10
arch/arm/mm/flush.c

@@ -13,6 +13,7 @@
 
 #include <asm/cacheflush.h>
 #include <asm/cachetype.h>
+#include <asm/highmem.h>
 #include <asm/smp_plat.h>
 #include <asm/system.h>
 #include <asm/tlbflush.h>
@@ -152,21 +153,25 @@ void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
 
 void __flush_dcache_page(struct address_space *mapping, struct page *page)
 {
-	void *addr = page_address(page);
-
 	/*
 	 * Writeback any data associated with the kernel mapping of this
 	 * page.  This ensures that data in the physical page is mutually
 	 * coherent with the kernels mapping.
 	 */
-#ifdef CONFIG_HIGHMEM
-	/*
-	 * kmap_atomic() doesn't set the page virtual address, and
-	 * kunmap_atomic() takes care of cache flushing already.
-	 */
-	if (addr)
-#endif
-		__cpuc_flush_dcache_area(addr, PAGE_SIZE);
+	if (!PageHighMem(page)) {
+		__cpuc_flush_dcache_area(page_address(page), PAGE_SIZE);
+	} else {
+		void *addr = kmap_high_get(page);
+		if (addr) {
+			__cpuc_flush_dcache_area(addr, PAGE_SIZE);
+			kunmap_high(page);
+		} else if (cache_is_vipt()) {
+			pte_t saved_pte;
+			addr = kmap_high_l1_vipt(page, &saved_pte);
+			__cpuc_flush_dcache_area(addr, PAGE_SIZE);
+			kunmap_high_l1_vipt(page, saved_pte);
+		}
+	}
 
 	/*
 	 * If this is a page cache page, and we have an aliasing VIPT cache,

+ 86 - 1
arch/arm/mm/highmem.c

@@ -79,7 +79,8 @@ void kunmap_atomic(void *kvaddr, enum km_type type)
 	unsigned int idx = type + KM_TYPE_NR * smp_processor_id();
 
 	if (kvaddr >= (void *)FIXADDR_START) {
-		__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
+		if (cache_is_vivt())
+			__cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE);
 #ifdef CONFIG_DEBUG_HIGHMEM
 		BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
 		set_pte_ext(TOP_PTE(vaddr), __pte(0), 0);
@@ -124,3 +125,87 @@ struct page *kmap_atomic_to_page(const void *ptr)
 	pte = TOP_PTE(vaddr);
 	return pte_page(*pte);
 }
+
+#ifdef CONFIG_CPU_CACHE_VIPT
+
+#include <linux/percpu.h>
+
+/*
+ * The VIVT cache of a highmem page is always flushed before the page
+ * is unmapped. Hence unmapped highmem pages need no cache maintenance
+ * in that case.
+ *
+ * However unmapped pages may still be cached with a VIPT cache, and
+ * it is not possible to perform cache maintenance on them using physical
+ * addresses unfortunately.  So we have no choice but to set up a temporary
+ * virtual mapping for that purpose.
+ *
+ * Yet this VIPT cache maintenance may be triggered from DMA support
+ * functions which are possibly called from interrupt context. As we don't
+ * want to keep interrupt disabled all the time when such maintenance is
+ * taking place, we therefore allow for some reentrancy by preserving and
+ * restoring the previous fixmap entry before the interrupted context is
+ * resumed.  If the reentrancy depth is 0 then there is no need to restore
+ * the previous fixmap, and leaving the current one in place allow it to
+ * be reused the next time without a TLB flush (common with DMA).
+ */
+
+static DEFINE_PER_CPU(int, kmap_high_l1_vipt_depth);
+
+void *kmap_high_l1_vipt(struct page *page, pte_t *saved_pte)
+{
+	unsigned int idx, cpu = smp_processor_id();
+	int *depth = &per_cpu(kmap_high_l1_vipt_depth, cpu);
+	unsigned long vaddr, flags;
+	pte_t pte, *ptep;
+
+	idx = KM_L1_CACHE + KM_TYPE_NR * cpu;
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+	ptep = TOP_PTE(vaddr);
+	pte = mk_pte(page, kmap_prot);
+
+	if (!in_interrupt())
+		preempt_disable();
+
+	raw_local_irq_save(flags);
+	(*depth)++;
+	if (pte_val(*ptep) == pte_val(pte)) {
+		*saved_pte = pte;
+	} else {
+		*saved_pte = *ptep;
+		set_pte_ext(ptep, pte, 0);
+		local_flush_tlb_kernel_page(vaddr);
+	}
+	raw_local_irq_restore(flags);
+
+	return (void *)vaddr;
+}
+
+void kunmap_high_l1_vipt(struct page *page, pte_t saved_pte)
+{
+	unsigned int idx, cpu = smp_processor_id();
+	int *depth = &per_cpu(kmap_high_l1_vipt_depth, cpu);
+	unsigned long vaddr, flags;
+	pte_t pte, *ptep;
+
+	idx = KM_L1_CACHE + KM_TYPE_NR * cpu;
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+	ptep = TOP_PTE(vaddr);
+	pte = mk_pte(page, kmap_prot);
+
+	BUG_ON(pte_val(*ptep) != pte_val(pte));
+	BUG_ON(*depth <= 0);
+
+	raw_local_irq_save(flags);
+	(*depth)--;
+	if (*depth != 0 && pte_val(pte) != pte_val(saved_pte)) {
+		set_pte_ext(ptep, saved_pte, 0);
+		local_flush_tlb_kernel_page(vaddr);
+	}
+	raw_local_irq_restore(flags);
+
+	if (!in_interrupt())
+		preempt_enable();
+}
+
+#endif  /* CONFIG_CPU_CACHE_VIPT */

+ 6 - 4
arch/arm/mm/mmu.c

@@ -1054,10 +1054,12 @@ void setup_mm_for_reboot(char mode)
 	pgd_t *pgd;
 	int i;
 
-	if (current->mm && current->mm->pgd)
-		pgd = current->mm->pgd;
-	else
-		pgd = init_mm.pgd;
+	/*
+	 * We need to access to user-mode page tables here. For kernel threads
+	 * we don't have any user-mode mappings so we use the context that we
+	 * "borrowed".
+	 */
+	pgd = current->active_mm->pgd;
 
 	base_pmdval = PMD_SECT_AP_WRITE | PMD_SECT_AP_READ | PMD_TYPE_SECT;
 	if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale())

+ 10 - 21
arch/arm/vfp/vfpmodule.c

@@ -428,26 +428,6 @@ static void vfp_pm_init(void)
 static inline void vfp_pm_init(void) { }
 #endif /* CONFIG_PM */
 
-/*
- * Synchronise the hardware VFP state of a thread other than current with the
- * saved one. This function is used by the ptrace mechanism.
- */
-#ifdef CONFIG_SMP
-void vfp_sync_hwstate(struct thread_info *thread)
-{
-}
-
-void vfp_flush_hwstate(struct thread_info *thread)
-{
-	/*
-	 * On SMP systems, the VFP state is automatically saved at every
-	 * context switch. We mark the thread VFP state as belonging to a
-	 * non-existent CPU so that the saved one will be reloaded when
-	 * needed.
-	 */
-	thread->vfpstate.hard.cpu = NR_CPUS;
-}
-#else
 void vfp_sync_hwstate(struct thread_info *thread)
 {
 	unsigned int cpu = get_cpu();
@@ -490,9 +470,18 @@ void vfp_flush_hwstate(struct thread_info *thread)
 		last_VFP_context[cpu] = NULL;
 	}
 
+#ifdef CONFIG_SMP
+	/*
+	 * For SMP we still have to take care of the case where the thread
+	 * migrates to another CPU and then back to the original CPU on which
+	 * the last VFP user is still the same thread. Mark the thread VFP
+	 * state as belonging to a non-existent CPU so that the saved one will
+	 * be reloaded in the above case.
+	 */
+	thread->vfpstate.hard.cpu = NR_CPUS;
+#endif
 	put_cpu();
 }
-#endif
 
 #include <linux/smp.h>