diff options
Diffstat (limited to 'extras/recipes-kernel/linux/linux-omap-psp-2.6.32/0038-ARM-Expose-some-CPU-control-registers-via-sysfs.patch')
-rw-r--r-- | extras/recipes-kernel/linux/linux-omap-psp-2.6.32/0038-ARM-Expose-some-CPU-control-registers-via-sysfs.patch | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/extras/recipes-kernel/linux/linux-omap-psp-2.6.32/0038-ARM-Expose-some-CPU-control-registers-via-sysfs.patch b/extras/recipes-kernel/linux/linux-omap-psp-2.6.32/0038-ARM-Expose-some-CPU-control-registers-via-sysfs.patch new file mode 100644 index 00000000..0b19cb70 --- /dev/null +++ b/extras/recipes-kernel/linux/linux-omap-psp-2.6.32/0038-ARM-Expose-some-CPU-control-registers-via-sysfs.patch @@ -0,0 +1,202 @@ +From 9eeb533964f73b661d23f7b145b96aa5d247e950 Mon Sep 17 00:00:00 2001 +From: Mans Rullgard <mans@mansr.com> +Date: Tue, 10 Nov 2009 00:39:21 +0000 +Subject: [PATCH 38/45] ARM: Expose some CPU control registers via sysfs + +This creates sysfs files under /sys/devices/system/cpu/cpuN +exposing the values of the control register, auxiliary control +register, and L2 cache auxiliary control register. Writing to +the files allows setting the value of bits which are safe to +change at any time. + +Signed-off-by: Mans Rullgard <mans@mansr.com> +--- + arch/arm/Kconfig | 5 ++ + arch/arm/kernel/Makefile | 1 + + arch/arm/kernel/sysfs_v7.c | 146 ++++++++++++++++++++++++++++++++++++++++++++ + 3 files changed, 152 insertions(+), 0 deletions(-) + create mode 100644 arch/arm/kernel/sysfs_v7.c + +diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig +index f5ded3c..2d370da 100644 +--- a/arch/arm/Kconfig ++++ b/arch/arm/Kconfig +@@ -1252,6 +1252,11 @@ config UACCESS_WITH_MEMCPY + However, if the CPU data cache is using a write-allocate mode, + this option is unlikely to provide any performance gain. + ++config CPU_V7_SYSFS ++ bool ++ depends on CPU_V7 && SYSFS ++ default y ++ + endmenu + + menu "Boot options" +diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile +index dd00f74..ee20134 100644 +--- a/arch/arm/kernel/Makefile ++++ b/arch/arm/kernel/Makefile +@@ -38,6 +38,7 @@ obj-$(CONFIG_ARM_THUMBEE) += thumbee.o + obj-$(CONFIG_KGDB) += kgdb.o + obj-$(CONFIG_ARM_UNWIND) += unwind.o + obj-$(CONFIG_HAVE_TCM) += tcm.o ++obj-$(CONFIG_CPU_V7_SYSFS) += sysfs_v7.o + + obj-$(CONFIG_CRUNCH) += crunch.o crunch-bits.o + AFLAGS_crunch-bits.o := -Wa,-mcpu=ep9312 +diff --git a/arch/arm/kernel/sysfs_v7.c b/arch/arm/kernel/sysfs_v7.c +new file mode 100644 +index 0000000..c05bf5f +--- /dev/null ++++ b/arch/arm/kernel/sysfs_v7.c +@@ -0,0 +1,146 @@ ++/* ++ * linux/arch/arm/kernel/sysfs.c ++ * ++ * Copyright (C) 2008 Mans Rullgard ++ * ++ * This program is free software; you can redistribute it and/or modify ++ * it under the terms of the GNU General Public License version 2 as ++ * published by the Free Software Foundation. ++ */ ++ ++#include <linux/kernel.h> ++#include <linux/cpu.h> ++#include <linux/sysdev.h> ++#include <linux/fs.h> ++ ++#define SETBITS(val, bits, new) \ ++ do { \ ++ val &= ~bits; \ ++ val |= new & bits; \ ++ } while (0) ++ ++#define SHOW_REG(name, opc1, crn, crm, opc2) \ ++static ssize_t name##_show(struct sys_device *dev, \ ++ struct sysdev_attribute *attr, \ ++ char *buf) \ ++{ \ ++ unsigned val; \ ++ asm ("mrc p15,"#opc1", %0,"#crn","#crm","#opc2 : "=r"(val)); \ ++ return snprintf(buf, PAGE_SIZE, "%08x\n", val); \ ++} ++ ++#define STORE_REG(name, opc1, crn, crm, opc2, bits) \ ++static ssize_t name##_store(struct sys_device *dev, \ ++ struct sysdev_attribute *attr, \ ++ const char *buf, size_t size) \ ++{ \ ++ char *end; \ ++ unsigned new = simple_strtoul(buf, &end, 0); \ ++ unsigned val; \ ++ \ ++ if (end == buf) \ ++ return -EINVAL; \ ++ \ ++ asm ("mrc p15,"#opc1", %0,"#crn","#crm","#opc2 : "=r"(val)); \ ++ SETBITS(val, bits, new); \ ++ asm ("mcr p15,"#opc1", %0,"#crn","#crm","#opc2 :: "r"(val)); \ ++ \ ++ return end - buf; \ ++} ++ ++#define RD_REG(name, opc1, crn, crm, opc2) \ ++ SHOW_REG(name, opc1, crn, crm, opc2) \ ++ static SYSDEV_ATTR(name, S_IRUGO|S_IWUSR, name##_show, NULL) ++ ++#define RDWR_REG(name, opc1, crn, crm, opc2, bits) \ ++ SHOW_REG(name, opc1, crn, crm, opc2) \ ++ STORE_REG(name, opc1, crn, crm, opc2, bits) \ ++ static SYSDEV_ATTR(name, S_IRUGO|S_IWUSR, name##_show, name##_store) ++ ++RDWR_REG(control, 0, c1, c0, 0, 0x802); ++ ++SHOW_REG(aux_ctl, 0, c1, c0, 1) ++ ++#ifdef CONFIG_ARCH_OMAP34XX ++static ssize_t aux_ctl_store(struct sys_device *dev, ++ struct sysdev_attribute *attr, ++ const char *buf, size_t size) ++{ ++ char *end; ++ unsigned new = simple_strtoul(buf, &end, 0); ++ unsigned val; ++ ++ if (end == buf) ++ return -EINVAL; ++ ++ asm ("mrc p15, 0, %0, c1, c0, 1" : "=r"(val)); ++ SETBITS(val, 0xff8, new); ++ val &= ~2; ++ asm ("mov r0, %0 \n\t" ++ "mov r12, #3 \n\t" ++ "smc #0 \n\t" ++ :: "r"(val) : "r0", "r12"); ++ ++ return end - buf; ++} ++#define AUX_WR S_IWUSR ++#else ++#define aux_ctl_store NULL ++#define AUX_WR 0 ++#endif ++ ++static SYSDEV_ATTR(aux_control, S_IRUGO|AUX_WR, aux_ctl_show, aux_ctl_store); ++ ++SHOW_REG(l2_aux_ctl, 1, c9, c0, 2) ++ ++#ifdef CONFIG_ARCH_OMAP34XX ++static ssize_t l2_aux_ctl_store(struct sys_device *dev, ++ struct sysdev_attribute *attr, ++ const char *buf, size_t size) ++{ ++ char *end; ++ unsigned new = simple_strtoul(buf, &end, 0); ++ unsigned val; ++ ++ if (end == buf) ++ return -EINVAL; ++ ++ asm ("mrc p15, 1, %0, c9, c0, 2" : "=r"(val)); ++ SETBITS(val, 0xbc00000, new); ++ asm ("mov r0, %0 \n\t" ++ "mov r12, #2 \n\t" ++ "smc #0 \n\t" ++ :: "r"(val) : "r0", "r12"); ++ ++ return end - buf; ++} ++#define L2AUX_WR S_IWUSR ++#else ++#define l2_aux_ctl_store NULL ++#define L2AUX_WR 0 ++#endif ++ ++static SYSDEV_ATTR(l2_aux_control, S_IRUGO|L2AUX_WR, ++ l2_aux_ctl_show, l2_aux_ctl_store); ++ ++#define REG_ATTR(sysdev, name) \ ++ do { \ ++ int err = sysfs_create_file(&sysdev->kobj, &name.attr); \ ++ WARN_ON(err != 0); \ ++ } while (0) ++ ++static int __init cpu_sysfs_init(void) ++{ ++ struct sys_device *sysdev; ++ int cpu; ++ ++ for_each_possible_cpu(cpu) { ++ sysdev = get_cpu_sysdev(cpu); ++ REG_ATTR(sysdev, attr_control); ++ REG_ATTR(sysdev, attr_aux_control); ++ REG_ATTR(sysdev, attr_l2_aux_control); ++ } ++ ++ return 0; ++} ++device_initcall(cpu_sysfs_init); +-- +1.6.6.1 + |