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-rw-r--r--arch/arm/kernel/Makefile2
-rw-r--r--arch/arm/kernel/kprobes-test.c66
-rw-r--r--arch/arm/kernel/opcodes.c72
-rw-r--r--arch/arm/kernel/smp_twd.c95
-rw-r--r--arch/arm/kernel/swp_emulate.c16
-rw-r--r--arch/arm/kernel/tcm.c22
6 files changed, 203 insertions, 70 deletions
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 16eed6aebfa4..43b740d0e374 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -13,7 +13,7 @@ CFLAGS_REMOVE_return_address.o = -pg
# Object file lists.
-obj-y := elf.o entry-armv.o entry-common.o irq.o \
+obj-y := elf.o entry-armv.o entry-common.o irq.o opcodes.o \
process.o ptrace.o return_address.o setup.o signal.o \
sys_arm.o stacktrace.o time.o traps.o
diff --git a/arch/arm/kernel/kprobes-test.c b/arch/arm/kernel/kprobes-test.c
index e17cdd6d90d8..1862d8f2fd44 100644
--- a/arch/arm/kernel/kprobes-test.c
+++ b/arch/arm/kernel/kprobes-test.c
@@ -202,6 +202,8 @@
#include <linux/slab.h>
#include <linux/kprobes.h>
+#include <asm/opcodes.h>
+
#include "kprobes.h"
#include "kprobes-test.h"
@@ -1050,65 +1052,9 @@ static int test_instance;
static unsigned long test_check_cc(int cc, unsigned long cpsr)
{
- unsigned long temp;
-
- switch (cc) {
- case 0x0: /* eq */
- return cpsr & PSR_Z_BIT;
-
- case 0x1: /* ne */
- return (~cpsr) & PSR_Z_BIT;
-
- case 0x2: /* cs */
- return cpsr & PSR_C_BIT;
-
- case 0x3: /* cc */
- return (~cpsr) & PSR_C_BIT;
-
- case 0x4: /* mi */
- return cpsr & PSR_N_BIT;
-
- case 0x5: /* pl */
- return (~cpsr) & PSR_N_BIT;
-
- case 0x6: /* vs */
- return cpsr & PSR_V_BIT;
-
- case 0x7: /* vc */
- return (~cpsr) & PSR_V_BIT;
+ int ret = arm_check_condition(cc << 28, cpsr);
- case 0x8: /* hi */
- cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
- return cpsr & PSR_C_BIT;
-
- case 0x9: /* ls */
- cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */
- return (~cpsr) & PSR_C_BIT;
-
- case 0xa: /* ge */
- cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- return (~cpsr) & PSR_N_BIT;
-
- case 0xb: /* lt */
- cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- return cpsr & PSR_N_BIT;
-
- case 0xc: /* gt */
- temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
- return (~temp) & PSR_N_BIT;
-
- case 0xd: /* le */
- temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */
- temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */
- return temp & PSR_N_BIT;
-
- case 0xe: /* al */
- case 0xf: /* unconditional */
- return true;
- }
- BUG();
- return false;
+ return (ret != ARM_OPCODE_CONDTEST_FAIL);
}
static int is_last_scenario;
@@ -1128,7 +1074,9 @@ static unsigned long test_context_cpsr(int scenario)
if (!test_case_is_thumb) {
/* Testing ARM code */
- probe_should_run = test_check_cc(current_instruction >> 28, cpsr) != 0;
+ int cc = current_instruction >> 28;
+
+ probe_should_run = test_check_cc(cc, cpsr) != 0;
if (scenario == 15)
is_last_scenario = true;
diff --git a/arch/arm/kernel/opcodes.c b/arch/arm/kernel/opcodes.c
new file mode 100644
index 000000000000..f8179c6a817f
--- /dev/null
+++ b/arch/arm/kernel/opcodes.c
@@ -0,0 +1,72 @@
+/*
+ * linux/arch/arm/kernel/opcodes.c
+ *
+ * A32 condition code lookup feature moved from nwfpe/fpopcode.c
+ *
+ * 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/module.h>
+#include <asm/opcodes.h>
+
+#define ARM_OPCODE_CONDITION_UNCOND 0xf
+
+/*
+ * condition code lookup table
+ * index into the table is test code: EQ, NE, ... LT, GT, AL, NV
+ *
+ * bit position in short is condition code: NZCV
+ */
+static const unsigned short cc_map[16] = {
+ 0xF0F0, /* EQ == Z set */
+ 0x0F0F, /* NE */
+ 0xCCCC, /* CS == C set */
+ 0x3333, /* CC */
+ 0xFF00, /* MI == N set */
+ 0x00FF, /* PL */
+ 0xAAAA, /* VS == V set */
+ 0x5555, /* VC */
+ 0x0C0C, /* HI == C set && Z clear */
+ 0xF3F3, /* LS == C clear || Z set */
+ 0xAA55, /* GE == (N==V) */
+ 0x55AA, /* LT == (N!=V) */
+ 0x0A05, /* GT == (!Z && (N==V)) */
+ 0xF5FA, /* LE == (Z || (N!=V)) */
+ 0xFFFF, /* AL always */
+ 0 /* NV */
+};
+
+/*
+ * Returns:
+ * ARM_OPCODE_CONDTEST_FAIL - if condition fails
+ * ARM_OPCODE_CONDTEST_PASS - if condition passes (including AL)
+ * ARM_OPCODE_CONDTEST_UNCOND - if NV condition, or separate unconditional
+ * opcode space from v5 onwards
+ *
+ * Code that tests whether a conditional instruction would pass its condition
+ * check should check that return value == ARM_OPCODE_CONDTEST_PASS.
+ *
+ * Code that tests if a condition means that the instruction would be executed
+ * (regardless of conditional or unconditional) should instead check that the
+ * return value != ARM_OPCODE_CONDTEST_FAIL.
+ */
+asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr)
+{
+ u32 cc_bits = opcode >> 28;
+ u32 psr_cond = psr >> 28;
+ unsigned int ret;
+
+ if (cc_bits != ARM_OPCODE_CONDITION_UNCOND) {
+ if ((cc_map[cc_bits] >> (psr_cond)) & 1)
+ ret = ARM_OPCODE_CONDTEST_PASS;
+ else
+ ret = ARM_OPCODE_CONDTEST_FAIL;
+ } else {
+ ret = ARM_OPCODE_CONDTEST_UNCOND;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(arm_check_condition);
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index a8a6682d6b52..c8e938553d47 100644
--- a/arch/arm/kernel/smp_twd.c
+++ b/arch/arm/kernel/smp_twd.c
@@ -10,8 +10,11 @@
*/
#include <linux/init.h>
#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
#include <linux/delay.h>
#include <linux/device.h>
+#include <linux/err.h>
#include <linux/smp.h>
#include <linux/jiffies.h>
#include <linux/clockchips.h>
@@ -25,6 +28,7 @@
/* set up by the platform code */
void __iomem *twd_base;
+static struct clk *twd_clk;
static unsigned long twd_timer_rate;
static struct clock_event_device __percpu **twd_evt;
@@ -89,6 +93,52 @@ void twd_timer_stop(struct clock_event_device *clk)
disable_percpu_irq(clk->irq);
}
+#ifdef CONFIG_CPU_FREQ
+
+/*
+ * Updates clockevent frequency when the cpu frequency changes.
+ * Called on the cpu that is changing frequency with interrupts disabled.
+ */
+static void twd_update_frequency(void *data)
+{
+ twd_timer_rate = clk_get_rate(twd_clk);
+
+ clockevents_update_freq(*__this_cpu_ptr(twd_evt), twd_timer_rate);
+}
+
+static int twd_cpufreq_transition(struct notifier_block *nb,
+ unsigned long state, void *data)
+{
+ struct cpufreq_freqs *freqs = data;
+
+ /*
+ * The twd clock events must be reprogrammed to account for the new
+ * frequency. The timer is local to a cpu, so cross-call to the
+ * changing cpu.
+ */
+ if (state == CPUFREQ_POSTCHANGE || state == CPUFREQ_RESUMECHANGE)
+ smp_call_function_single(freqs->cpu, twd_update_frequency,
+ NULL, 1);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block twd_cpufreq_nb = {
+ .notifier_call = twd_cpufreq_transition,
+};
+
+static int twd_cpufreq_init(void)
+{
+ if (!IS_ERR(twd_clk))
+ return cpufreq_register_notifier(&twd_cpufreq_nb,
+ CPUFREQ_TRANSITION_NOTIFIER);
+
+ return 0;
+}
+core_initcall(twd_cpufreq_init);
+
+#endif
+
static void __cpuinit twd_calibrate_rate(void)
{
unsigned long count;
@@ -140,6 +190,35 @@ static irqreturn_t twd_handler(int irq, void *dev_id)
return IRQ_NONE;
}
+static struct clk *twd_get_clock(void)
+{
+ struct clk *clk;
+ int err;
+
+ clk = clk_get_sys("smp_twd", NULL);
+ if (IS_ERR(clk)) {
+ pr_err("smp_twd: clock not found: %d\n", (int)PTR_ERR(clk));
+ return clk;
+ }
+
+ err = clk_prepare(clk);
+ if (err) {
+ pr_err("smp_twd: clock failed to prepare: %d\n", err);
+ clk_put(clk);
+ return ERR_PTR(err);
+ }
+
+ err = clk_enable(clk);
+ if (err) {
+ pr_err("smp_twd: clock failed to enable: %d\n", err);
+ clk_unprepare(clk);
+ clk_put(clk);
+ return ERR_PTR(err);
+ }
+
+ return clk;
+}
+
/*
* Setup the local clock events for a CPU.
*/
@@ -165,7 +244,13 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk)
}
}
- twd_calibrate_rate();
+ if (!twd_clk)
+ twd_clk = twd_get_clock();
+
+ if (!IS_ERR_OR_NULL(twd_clk))
+ twd_timer_rate = clk_get_rate(twd_clk);
+ else
+ twd_calibrate_rate();
clk->name = "local_timer";
clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
@@ -173,15 +258,11 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk)
clk->rating = 350;
clk->set_mode = twd_set_mode;
clk->set_next_event = twd_set_next_event;
- clk->shift = 20;
- clk->mult = div_sc(twd_timer_rate, NSEC_PER_SEC, clk->shift);
- clk->max_delta_ns = clockevent_delta2ns(0xffffffff, clk);
- clk->min_delta_ns = clockevent_delta2ns(0xf, clk);
this_cpu_clk = __this_cpu_ptr(twd_evt);
*this_cpu_clk = clk;
- clockevents_register_device(clk);
-
+ clockevents_config_and_register(clk, twd_timer_rate,
+ 0xf, 0xffffffff);
enable_percpu_irq(clk->irq, 0);
}
diff --git a/arch/arm/kernel/swp_emulate.c b/arch/arm/kernel/swp_emulate.c
index 5f452f8fde05..df745188f5de 100644
--- a/arch/arm/kernel/swp_emulate.c
+++ b/arch/arm/kernel/swp_emulate.c
@@ -25,6 +25,7 @@
#include <linux/syscalls.h>
#include <linux/perf_event.h>
+#include <asm/opcodes.h>
#include <asm/traps.h>
#include <asm/uaccess.h>
@@ -185,6 +186,21 @@ static int swp_handler(struct pt_regs *regs, unsigned int instr)
perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, regs->ARM_pc);
+ res = arm_check_condition(instr, regs->ARM_cpsr);
+ switch (res) {
+ case ARM_OPCODE_CONDTEST_PASS:
+ break;
+ case ARM_OPCODE_CONDTEST_FAIL:
+ /* Condition failed - return to next instruction */
+ regs->ARM_pc += 4;
+ return 0;
+ case ARM_OPCODE_CONDTEST_UNCOND:
+ /* If unconditional encoding - not a SWP, undef */
+ return -EFAULT;
+ default:
+ return -EINVAL;
+ }
+
if (current->pid != previous_pid) {
pr_debug("\"%s\" (%ld) uses deprecated SWP{B} instruction\n",
current->comm, (unsigned long)current->pid);
diff --git a/arch/arm/kernel/tcm.c b/arch/arm/kernel/tcm.c
index 30e302d33e0a..01ec453bb924 100644
--- a/arch/arm/kernel/tcm.c
+++ b/arch/arm/kernel/tcm.c
@@ -180,9 +180,9 @@ static int __init setup_tcm_bank(u8 type, u8 bank, u8 banks,
*/
void __init tcm_init(void)
{
- u32 tcm_status = read_cpuid_tcmstatus();
- u8 dtcm_banks = (tcm_status >> 16) & 0x03;
- u8 itcm_banks = (tcm_status & 0x03);
+ u32 tcm_status;
+ u8 dtcm_banks;
+ u8 itcm_banks;
size_t dtcm_code_sz = &__edtcm_data - &__sdtcm_data;
size_t itcm_code_sz = &__eitcm_text - &__sitcm_text;
char *start;
@@ -191,6 +191,22 @@ void __init tcm_init(void)
int ret;
int i;
+ /*
+ * Prior to ARMv5 there is no TCM, and trying to read the status
+ * register will hang the processor.
+ */
+ if (cpu_architecture() < CPU_ARCH_ARMv5) {
+ if (dtcm_code_sz || itcm_code_sz)
+ pr_info("CPU TCM: %u bytes of DTCM and %u bytes of "
+ "ITCM code compiled in, but no TCM present "
+ "in pre-v5 CPU\n", dtcm_code_sz, itcm_code_sz);
+ return;
+ }
+
+ tcm_status = read_cpuid_tcmstatus();
+ dtcm_banks = (tcm_status >> 16) & 0x03;
+ itcm_banks = (tcm_status & 0x03);
+
/* Values greater than 2 for D/ITCM banks are "reserved" */
if (dtcm_banks > 2)
dtcm_banks = 0;