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-rw-r--r--arch/arc/kernel/ctx_sw_asm.S4
-rw-r--r--arch/arc/kernel/devtree.c4
-rw-r--r--arch/arc/kernel/entry.S72
-rw-r--r--arch/arc/kernel/head.S78
-rw-r--r--arch/arc/kernel/irq.c18
-rw-r--r--arch/arc/kernel/perf_event.c4
-rw-r--r--arch/arc/kernel/process.c23
-rw-r--r--arch/arc/kernel/ptrace.c4
-rw-r--r--arch/arc/kernel/setup.c48
-rw-r--r--arch/arc/kernel/smp.c141
-rw-r--r--arch/arc/kernel/time.c46
-rw-r--r--arch/arc/kernel/troubleshoot.c10
-rw-r--r--arch/arc/kernel/vmlinux.lds.S2
13 files changed, 268 insertions, 186 deletions
diff --git a/arch/arc/kernel/ctx_sw_asm.S b/arch/arc/kernel/ctx_sw_asm.S
index 65690e7fcc8..e248594097e 100644
--- a/arch/arc/kernel/ctx_sw_asm.S
+++ b/arch/arc/kernel/ctx_sw_asm.S
@@ -10,9 +10,9 @@
* -This is the more "natural" hand written assembler
*/
+#include <linux/linkage.h>
#include <asm/entry.h> /* For the SAVE_* macros */
#include <asm/asm-offsets.h>
-#include <asm/linkage.h>
#define KSP_WORD_OFF ((TASK_THREAD + THREAD_KSP) / 4)
@@ -62,4 +62,4 @@ __switch_to:
ld.ab blink, [sp, 4]
j [blink]
-ARC_EXIT __switch_to
+END(__switch_to)
diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
index b6dc4e21fd3..fffdb5e41b2 100644
--- a/arch/arc/kernel/devtree.c
+++ b/arch/arc/kernel/devtree.c
@@ -41,8 +41,8 @@ const struct machine_desc * __init setup_machine_fdt(void *dt)
{
const struct machine_desc *mdesc;
unsigned long dt_root;
- void *clk;
- unsigned long len;
+ const void *clk;
+ int len;
if (!early_init_dt_scan(dt))
return NULL;
diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S
index 47d09d07f09..83a046a7cd0 100644
--- a/arch/arc/kernel/entry.S
+++ b/arch/arc/kernel/entry.S
@@ -141,7 +141,7 @@ VECTOR EV_Extension ; 0x130, Extn Intruction Excp (0x26)
VECTOR reserved ; Reserved Exceptions
.endr
-#include <linux/linkage.h> /* ARC_{EXTRY,EXIT} */
+#include <linux/linkage.h> /* {EXTRY,EXIT} */
#include <asm/entry.h> /* SAVE_ALL_{INT1,INT2,SYS...} */
#include <asm/errno.h>
#include <asm/arcregs.h>
@@ -156,7 +156,7 @@ ARCFP_DATA int1_saved_reg
int1_saved_reg:
.zero 4
-/* Each Interrupt level needs it's own scratch */
+/* Each Interrupt level needs its own scratch */
#ifdef CONFIG_ARC_COMPACT_IRQ_LEVELS
ARCFP_DATA int2_saved_reg
@@ -184,7 +184,7 @@ reserved: ; processor restart
; ---------------------------------------------
; Level 2 ISR: Can interrupt a Level 1 ISR
; ---------------------------------------------
-ARC_ENTRY handle_interrupt_level2
+ENTRY(handle_interrupt_level2)
; TODO-vineetg for SMP this wont work
; free up r9 as scratchpad
@@ -225,14 +225,14 @@ ARC_ENTRY handle_interrupt_level2
b ret_from_exception
-ARC_EXIT handle_interrupt_level2
+END(handle_interrupt_level2)
#endif
; ---------------------------------------------
; Level 1 ISR
; ---------------------------------------------
-ARC_ENTRY handle_interrupt_level1
+ENTRY(handle_interrupt_level1)
/* free up r9 as scratchpad */
#ifdef CONFIG_SMP
@@ -265,7 +265,7 @@ ARC_ENTRY handle_interrupt_level1
sr r8, [AUX_IRQ_LV12] ; clear bit in Sticky Status Reg
b ret_from_exception
-ARC_EXIT handle_interrupt_level1
+END(handle_interrupt_level1)
;################### Non TLB Exception Handling #############################
@@ -273,7 +273,7 @@ ARC_EXIT handle_interrupt_level1
; Instruction Error Exception Handler
; ---------------------------------------------
-ARC_ENTRY instr_service
+ENTRY(instr_service)
EXCEPTION_PROLOGUE
@@ -284,13 +284,13 @@ ARC_ENTRY instr_service
bl do_insterror_or_kprobe
b ret_from_exception
-ARC_EXIT instr_service
+END(instr_service)
; ---------------------------------------------
; Memory Error Exception Handler
; ---------------------------------------------
-ARC_ENTRY mem_service
+ENTRY(mem_service)
EXCEPTION_PROLOGUE
@@ -301,13 +301,13 @@ ARC_ENTRY mem_service
bl do_memory_error
b ret_from_exception
-ARC_EXIT mem_service
+END(mem_service)
; ---------------------------------------------
; Machine Check Exception Handler
; ---------------------------------------------
-ARC_ENTRY EV_MachineCheck
+ENTRY(EV_MachineCheck)
EXCEPTION_PROLOGUE
@@ -331,13 +331,13 @@ ARC_ENTRY EV_MachineCheck
j do_machine_check_fault
-ARC_EXIT EV_MachineCheck
+END(EV_MachineCheck)
; ---------------------------------------------
; Protection Violation Exception Handler
; ---------------------------------------------
-ARC_ENTRY EV_TLBProtV
+ENTRY(EV_TLBProtV)
EXCEPTION_PROLOGUE
@@ -385,12 +385,12 @@ ARC_ENTRY EV_TLBProtV
b ret_from_exception
-ARC_EXIT EV_TLBProtV
+END(EV_TLBProtV)
; ---------------------------------------------
; Privilege Violation Exception Handler
; ---------------------------------------------
-ARC_ENTRY EV_PrivilegeV
+ENTRY(EV_PrivilegeV)
EXCEPTION_PROLOGUE
@@ -401,12 +401,12 @@ ARC_ENTRY EV_PrivilegeV
bl do_privilege_fault
b ret_from_exception
-ARC_EXIT EV_PrivilegeV
+END(EV_PrivilegeV)
; ---------------------------------------------
; Extension Instruction Exception Handler
; ---------------------------------------------
-ARC_ENTRY EV_Extension
+ENTRY(EV_Extension)
EXCEPTION_PROLOGUE
@@ -417,7 +417,7 @@ ARC_ENTRY EV_Extension
bl do_extension_fault
b ret_from_exception
-ARC_EXIT EV_Extension
+END(EV_Extension)
;######################### System Call Tracing #########################
@@ -473,7 +473,7 @@ trap_with_param:
lr r0, [efa]
mov r1, sp
- ; Now that we have read EFA, its safe to do "fake" rtie
+ ; Now that we have read EFA, it is safe to do "fake" rtie
; and get out of CPU exception mode
FAKE_RET_FROM_EXCPN r11
@@ -504,7 +504,7 @@ trap_with_param:
; (2) Break Points
;------------------------------------------------------------------
-ARC_ENTRY EV_Trap
+ENTRY(EV_Trap)
EXCEPTION_PROLOGUE
@@ -534,9 +534,9 @@ ARC_ENTRY EV_Trap
jl [r9] ; Entry into Sys Call Handler
; fall through to ret_from_system_call
-ARC_EXIT EV_Trap
+END(EV_Trap)
-ARC_ENTRY ret_from_system_call
+ENTRY(ret_from_system_call)
st r0, [sp, PT_r0] ; sys call return value in pt_regs
@@ -546,7 +546,7 @@ ARC_ENTRY ret_from_system_call
;
; If ret to user mode do we need to handle signals, schedule() et al.
-ARC_ENTRY ret_from_exception
+ENTRY(ret_from_exception)
; Pre-{IRQ,Trap,Exception} K/U mode from pt_regs->status32
ld r8, [sp, PT_status32] ; returning to User/Kernel Mode
@@ -614,11 +614,13 @@ resume_user_mode_begin:
resume_kernel_mode:
-#ifdef CONFIG_PREEMPT
-
- ; This is a must for preempt_schedule_irq()
+ ; Disable Interrupts from this point on
+ ; CONFIG_PREEMPT: This is a must for preempt_schedule_irq()
+ ; !CONFIG_PREEMPT: To ensure restore_regs is intr safe
IRQ_DISABLE r9
+#ifdef CONFIG_PREEMPT
+
; Can't preempt if preemption disabled
GET_CURR_THR_INFO_FROM_SP r10
ld r8, [r10, THREAD_INFO_PREEMPT_COUNT]
@@ -676,9 +678,9 @@ not_exception:
brne r9, event_IRQ2, 149f
;------------------------------------------------------------------
- ; if L2 IRQ interrupted a L1 ISR, we'd disbaled preemption earlier
- ; so that sched doesnt move to new task, causing L1 to be delayed
- ; undeterministically. Now that we've achieved that, lets reset
+ ; if L2 IRQ interrupted an L1 ISR, we'd disabled preemption earlier
+ ; so that sched doesn't move to new task, causing L1 to be delayed
+ ; undeterministically. Now that we've achieved that, let's reset
; things to what they were, before returning from L2 context
;----------------------------------------------------------------
@@ -726,15 +728,15 @@ not_level1_interrupt:
debug_marker_syscall:
rtie
-ARC_EXIT ret_from_exception
+END(ret_from_exception)
-ARC_ENTRY ret_from_fork
+ENTRY(ret_from_fork)
; when the forked child comes here from the __switch_to function
; r0 has the last task pointer.
; put last task in scheduler queue
bl @schedule_tail
- ; If kernel thread, jump to it's entry-point
+ ; If kernel thread, jump to its entry-point
ld r9, [sp, PT_status32]
brne r9, 0, 1f
@@ -745,11 +747,11 @@ ARC_ENTRY ret_from_fork
; special case of kernel_thread entry point returning back due to
; kernel_execve() - pretend return from syscall to ret to userland
b ret_from_exception
-ARC_EXIT ret_from_fork
+END(ret_from_fork)
;################### Special Sys Call Wrappers ##########################
-ARC_ENTRY sys_clone_wrapper
+ENTRY(sys_clone_wrapper)
SAVE_CALLEE_SAVED_USER
bl @sys_clone
DISCARD_CALLEE_SAVED_USER
@@ -759,7 +761,7 @@ ARC_ENTRY sys_clone_wrapper
bnz tracesys_exit
b ret_from_system_call
-ARC_EXIT sys_clone_wrapper
+END(sys_clone_wrapper)
#ifdef CONFIG_ARC_DW2_UNWIND
; Workaround for bug 94179 (STAR ):
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
index 2c878e964a6..4d2481bd8b9 100644
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -12,10 +12,42 @@
* to skip certain things during boot on simulator
*/
+#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/entry.h>
-#include <linux/linkage.h>
#include <asm/arcregs.h>
+#include <asm/cache.h>
+
+.macro CPU_EARLY_SETUP
+
+ ; Setting up Vectror Table (in case exception happens in early boot
+ sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+
+ ; Disable I-cache/D-cache if kernel so configured
+ lr r5, [ARC_REG_IC_BCR]
+ breq r5, 0, 1f ; I$ doesn't exist
+ lr r5, [ARC_REG_IC_CTRL]
+#ifdef CONFIG_ARC_HAS_ICACHE
+ bclr r5, r5, 0 ; 0 - Enable, 1 is Disable
+#else
+ bset r5, r5, 0 ; I$ exists, but is not used
+#endif
+ sr r5, [ARC_REG_IC_CTRL]
+
+1:
+ lr r5, [ARC_REG_DC_BCR]
+ breq r5, 0, 1f ; D$ doesn't exist
+ lr r5, [ARC_REG_DC_CTRL]
+ bclr r5, r5, 6 ; Invalidate (discard w/o wback)
+#ifdef CONFIG_ARC_HAS_DCACHE
+ bclr r5, r5, 0 ; Enable (+Inv)
+#else
+ bset r5, r5, 0 ; Disable (+Inv)
+#endif
+ sr r5, [ARC_REG_DC_CTRL]
+
+1:
+.endm
.cpu A7
@@ -24,13 +56,13 @@
.globl stext
stext:
;-------------------------------------------------------------------
- ; Don't clobber r0-r4 yet. It might have bootloader provided info
+ ; Don't clobber r0-r2 yet. It might have bootloader provided info
;-------------------------------------------------------------------
- sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+ CPU_EARLY_SETUP
#ifdef CONFIG_SMP
- ; Only Boot (Master) proceeds. Others wait in platform dependent way
+ ; Ensure Boot (Master) proceeds. Others wait in platform dependent way
; IDENTITY Reg [ 3 2 1 0 ]
; (cpu-id) ^^^ => Zero for UP ARC700
; => #Core-ID if SMP (Master 0)
@@ -39,35 +71,25 @@ stext:
; need to make sure only boot cpu takes this path.
GET_CPU_ID r5
cmp r5, 0
- jnz arc_platform_smp_wait_to_boot
+ mov.ne r0, r5
+ jne arc_platform_smp_wait_to_boot
#endif
; Clear BSS before updating any globals
; XXX: use ZOL here
mov r5, __bss_start
- mov r6, __bss_stop
+ sub r6, __bss_stop, r5
+ lsr.f lp_count, r6, 2
+ lpnz 1f
+ st.ab 0, [r5, 4]
1:
- st.ab 0, [r5,4]
- brlt r5, r6, 1b
-#ifdef CONFIG_CMDLINE_UBOOT
- ; support for bootloader provided cmdline
- ; If cmdline passed by u-boot, then
- ; r0 = 1 (because ATAGS parsing, now retired, used to use 0)
- ; r1 = magic number (board identity)
- ; r2 = addr of cmdline string (somewhere in memory/flash)
-
- brne r0, 1, .Lother_bootup_chores ; u-boot didn't pass cmdline
- breq r2, 0, .Lother_bootup_chores ; or cmdline is NULL
-
- mov r5, @command_line
-1:
- ldb.ab r6, [r2, 1]
- breq r6, 0, .Lother_bootup_chores
- b.d 1b
- stb.ab r6, [r5, 1]
-#endif
-
-.Lother_bootup_chores:
+ ; Uboot - kernel ABI
+ ; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2
+ ; r1 = magic number (board identity, unused as of now
+ ; r2 = pointer to uboot provided cmdline or external DTB in mem
+ ; These are handled later in setup_arch()
+ st r0, [@uboot_tag]
+ st r2, [@uboot_arg]
; Identify if running on ISS vs Silicon
; IDENTITY Reg [ 3 2 1 0 ]
@@ -101,7 +123,7 @@ stext:
first_lines_of_secondary:
- sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+ CPU_EARLY_SETUP
; setup per-cpu idle task as "current" on this CPU
ld r0, [@secondary_idle_tsk]
diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
index a4b141ee9a6..7d653c0d077 100644
--- a/arch/arc/kernel/irq.c
+++ b/arch/arc/kernel/irq.c
@@ -150,24 +150,6 @@ void arch_do_IRQ(unsigned int irq, struct pt_regs *regs)
set_irq_regs(old_regs);
}
-int get_hw_config_num_irq(void)
-{
- uint32_t val = read_aux_reg(ARC_REG_VECBASE_BCR);
-
- switch (val & 0x03) {
- case 0:
- return 16;
- case 1:
- return 32;
- case 2:
- return 8;
- default:
- return 0;
- }
-
- return 0;
-}
-
/*
* arch_local_irq_enable - Enable interrupts.
*
diff --git a/arch/arc/kernel/perf_event.c b/arch/arc/kernel/perf_event.c
index e46d81f7097..63177e4cb66 100644
--- a/arch/arc/kernel/perf_event.c
+++ b/arch/arc/kernel/perf_event.c
@@ -79,9 +79,9 @@ static int arc_pmu_cache_event(u64 config)
cache_result = (config >> 16) & 0xff;
if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
return -EINVAL;
- if (cache_type >= PERF_COUNT_HW_CACHE_OP_MAX)
+ if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
return -EINVAL;
- if (cache_type >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+ if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
return -EINVAL;
ret = arc_pmu_cache_map[cache_type][cache_op][cache_result];
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index 07a3a968fe4..fdd89715d2d 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -151,6 +151,29 @@ int copy_thread(unsigned long clone_flags,
}
/*
+ * Do necessary setup to start up a new user task
+ */
+void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp)
+{
+ set_fs(USER_DS); /* user space */
+
+ regs->sp = usp;
+ regs->ret = pc;
+
+ /*
+ * [U]ser Mode bit set
+ * [L] ZOL loop inhibited to begin with - cleared by a LP insn
+ * Interrupts enabled
+ */
+ regs->status32 = STATUS_U_MASK | STATUS_L_MASK |
+ STATUS_E1_MASK | STATUS_E2_MASK;
+
+ /* bogus seed values for debugging */
+ regs->lp_start = 0x10;
+ regs->lp_end = 0x80;
+}
+
+/*
* Some archs flush debug and FPU info here
*/
void flush_thread(void)
diff --git a/arch/arc/kernel/ptrace.c b/arch/arc/kernel/ptrace.c
index 5d76706139d..13b3ffb27a3 100644
--- a/arch/arc/kernel/ptrace.c
+++ b/arch/arc/kernel/ptrace.c
@@ -146,6 +146,10 @@ long arch_ptrace(struct task_struct *child, long request,
pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data);
switch (request) {
+ case PTRACE_GET_THREAD_AREA:
+ ret = put_user(task_thread_info(child)->thr_ptr,
+ (unsigned long __user *)data);
+ break;
default:
ret = ptrace_request(child, request, addr, data);
break;
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 643eae4436e..119dddb752b 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -29,7 +29,10 @@
int running_on_hw = 1; /* vs. on ISS */
-char __initdata command_line[COMMAND_LINE_SIZE];
+/* Part of U-boot ABI: see head.S */
+int __initdata uboot_tag;
+char __initdata *uboot_arg;
+
const struct machine_desc *machine_desc;
struct task_struct *_current_task[NR_CPUS]; /* For stack switching */
@@ -311,19 +314,40 @@ void setup_processor(void)
arc_chk_fpu();
}
+static inline int is_kernel(unsigned long addr)
+{
+ if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
+ return 1;
+ return 0;
+}
+
void __init setup_arch(char **cmdline_p)
{
- /* This also populates @boot_command_line from /bootargs */
- machine_desc = setup_machine_fdt(__dtb_start);
- if (!machine_desc)
- panic("Embedded DT invalid\n");
-
- /* Append any u-boot provided cmdline */
-#ifdef CONFIG_CMDLINE_UBOOT
- /* Add a whitespace seperator between the 2 cmdlines */
- strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
- strlcat(boot_command_line, command_line, COMMAND_LINE_SIZE);
-#endif
+ /* make sure that uboot passed pointer to cmdline/dtb is valid */
+ if (uboot_tag && is_kernel((unsigned long)uboot_arg))
+ panic("Invalid uboot arg\n");
+
+ /* See if u-boot passed an external Device Tree blob */
+ machine_desc = setup_machine_fdt(uboot_arg); /* uboot_tag == 2 */
+ if (!machine_desc) {
+ /* No, so try the embedded one */
+ machine_desc = setup_machine_fdt(__dtb_start);
+ if (!machine_desc)
+ panic("Embedded DT invalid\n");
+
+ /*
+ * If we are here, it is established that @uboot_arg didn't
+ * point to DT blob. Instead if u-boot says it is cmdline,
+ * Appent to embedded DT cmdline.
+ * setup_machine_fdt() would have populated @boot_command_line
+ */
+ if (uboot_tag == 1) {
+ /* Ensure a whitespace between the 2 cmdlines */
+ strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
+ strlcat(boot_command_line, uboot_arg,
+ COMMAND_LINE_SIZE);
+ }
+ }
/* Save unparsed command line copy for /proc/cmdline */
*cmdline_p = boot_command_line;
diff --git a/arch/arc/kernel/smp.c b/arch/arc/kernel/smp.c
index c2f9ebbc38f..c802bb50060 100644
--- a/arch/arc/kernel/smp.c
+++ b/arch/arc/kernel/smp.c
@@ -138,7 +138,7 @@ void start_kernel_secondary(void)
if (machine_desc->init_smp)
machine_desc->init_smp(smp_processor_id());
- arc_local_timer_setup(cpu);
+ arc_local_timer_setup();
local_irq_enable();
preempt_disable();
@@ -197,51 +197,65 @@ int __init setup_profiling_timer(unsigned int multiplier)
/* Inter Processor Interrupt Handling */
/*****************************************************************************/
-/*
- * structures for inter-processor calls
- * A Collection of single bit ipi messages
- *
- */
-
-/*
- * TODO_rajesh investigate tlb message types.
- * IPI Timer not needed because each ARC has an individual Interrupting Timer
- */
enum ipi_msg_type {
- IPI_NOP = 0,
+ IPI_EMPTY = 0,
IPI_RESCHEDULE = 1,
IPI_CALL_FUNC,
- IPI_CPU_STOP
+ IPI_CPU_STOP,
};
-struct ipi_data {
- unsigned long bits;
-};
+/*
+ * In arches with IRQ for each msg type (above), receiver can use IRQ-id to
+ * figure out what msg was sent. For those which don't (ARC has dedicated IPI
+ * IRQ), the msg-type needs to be conveyed via per-cpu data
+ */
-static DEFINE_PER_CPU(struct ipi_data, ipi_data);
+static DEFINE_PER_CPU(unsigned long, ipi_data);
-static void ipi_send_msg(const struct cpumask *callmap, enum ipi_msg_type msg)
+static void ipi_send_msg_one(int cpu, enum ipi_msg_type msg)
{
+ unsigned long __percpu *ipi_data_ptr = per_cpu_ptr(&ipi_data, cpu);
+ unsigned long old, new;
unsigned long flags;
- unsigned int cpu;
+
+ pr_debug("%d Sending msg [%d] to %d\n", smp_processor_id(), msg, cpu);
local_irq_save(flags);
- for_each_cpu(cpu, callmap) {
- struct ipi_data *ipi = &per_cpu(ipi_data, cpu);
- set_bit(msg, &ipi->bits);
- }
+ /*
+ * Atomically write new msg bit (in case others are writing too),
+ * and read back old value
+ */
+ do {
+ new = old = *ipi_data_ptr;
+ new |= 1U << msg;
+ } while (cmpxchg(ipi_data_ptr, old, new) != old);
- /* Call the platform specific cross-CPU call function */
- if (plat_smp_ops.ipi_send)
- plat_smp_ops.ipi_send((void *)callmap);
+ /*
+ * Call the platform specific IPI kick function, but avoid if possible:
+ * Only do so if there's no pending msg from other concurrent sender(s).
+ * Otherwise, recevier will see this msg as well when it takes the
+ * IPI corresponding to that msg. This is true, even if it is already in
+ * IPI handler, because !@old means it has not yet dequeued the msg(s)
+ * so @new msg can be a free-loader
+ */
+ if (plat_smp_ops.ipi_send && !old)
+ plat_smp_ops.ipi_send(cpu);
local_irq_restore(flags);
}
+static void ipi_send_msg(const struct cpumask *callmap, enum ipi_msg_type msg)
+{
+ unsigned int cpu;
+
+ for_each_cpu(cpu, callmap)
+ ipi_send_msg_one(cpu, msg);
+}
+
void smp_send_reschedule(int cpu)
{
- ipi_send_msg(cpumask_of(cpu), IPI_RESCHEDULE);
+ ipi_send_msg_one(cpu, IPI_RESCHEDULE);
}
void smp_send_stop(void)
@@ -254,7 +268,7 @@ void smp_send_stop(void)
void arch_send_call_function_single_ipi(int cpu)
{
- ipi_send_msg(cpumask_of(cpu), IPI_CALL_FUNC);
+ ipi_send_msg_one(cpu, IPI_CALL_FUNC);
}
void arch_send_call_function_ipi_mask(const struct cpumask *mask)
@@ -265,33 +279,29 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask)
/*
* ipi_cpu_stop - handle IPI from smp_send_stop()
*/
-static void ipi_cpu_stop(unsigned int cpu)
+static void ipi_cpu_stop(void)
{
machine_halt();
}
-static inline void __do_IPI(unsigned long *ops, struct ipi_data *ipi, int cpu)
+static inline void __do_IPI(unsigned long msg)
{
- unsigned long msg = 0;
-
- do {
- msg = find_next_bit(ops, BITS_PER_LONG, msg+1);
+ switch (msg) {
+ case IPI_RESCHEDULE:
+ scheduler_ipi();
+ break;
- switch (msg) {
- case IPI_RESCHEDULE:
- scheduler_ipi();
- break;
+ case IPI_CALL_FUNC:
+ generic_smp_call_function_interrupt();
+ break;
- case IPI_CALL_FUNC:
- generic_smp_call_function_interrupt();
- break;
-
- case IPI_CPU_STOP:
- ipi_cpu_stop(cpu);
- break;
- }
- } while (msg < BITS_PER_LONG);
+ case IPI_CPU_STOP:
+ ipi_cpu_stop();
+ break;
+ default:
+ pr_warn("IPI with unexpected msg %ld\n", msg);
+ }
}
/*
@@ -300,19 +310,25 @@ static inline void __do_IPI(unsigned long *ops, struct ipi_data *ipi, int cpu)
*/
irqreturn_t do_IPI(int irq, void *dev_id)
{
- int cpu = smp_processor_id();
- struct ipi_data *ipi = &per_cpu(ipi_data, cpu);
- unsigned long ops;
+ unsigned long pending;
+
+ pr_debug("IPI [%ld] received on cpu %d\n",
+ *this_cpu_ptr(&ipi_data), smp_processor_id());
if (plat_smp_ops.ipi_clear)
- plat_smp_ops.ipi_clear(cpu, irq);
+ plat_smp_ops.ipi_clear(irq);
/*
- * XXX: is this loop really needed
- * And do we need to move ipi_clean inside
+ * "dequeue" the msg corresponding to this IPI (and possibly other
+ * piggybacked msg from elided IPIs: see ipi_send_msg_one() above)
*/
- while ((ops = xchg(&ipi->bits, 0)) != 0)
- __do_IPI(&ops, ipi, cpu);
+ pending = xchg(this_cpu_ptr(&ipi_data), 0);
+
+ do {
+ unsigned long msg = __ffs(pending);
+ __do_IPI(msg);
+ pending &= ~(1U << msg);
+ } while (pending);
return IRQ_HANDLED;
}
@@ -321,8 +337,19 @@ irqreturn_t do_IPI(int irq, void *dev_id)
* API called by platform code to hookup arch-common ISR to their IPI IRQ
*/
static DEFINE_PER_CPU(int, ipi_dev);
+
+static struct irqaction arc_ipi_irq = {
+ .name = "IPI Interrupt",
+ .flags = IRQF_PERCPU,
+ .handler = do_IPI,
+};
+
int smp_ipi_irq_setup(int cpu, int irq)
{
- int *dev_id = &per_cpu(ipi_dev, smp_processor_id());
- return request_percpu_irq(irq, do_IPI, "IPI Interrupt", dev_id);
+ if (!cpu)
+ return setup_irq(irq, &arc_ipi_irq);
+ else
+ arch_unmask_irq(irq);
+
+ return 0;
}
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c
index e5f3a837fb3..36c2aa99436 100644
--- a/arch/arc/kernel/time.c
+++ b/arch/arc/kernel/time.c
@@ -155,22 +155,6 @@ static void arc_timer_event_setup(unsigned int limit)
write_aux_reg(ARC_REG_TIMER0_CTRL, TIMER_CTRL_IE | TIMER_CTRL_NH);
}
-/*
- * Acknowledge the interrupt (oneshot) and optionally re-arm it (periodic)
- * -Any write to CTRL Reg will ack the intr (NH bit: Count when not halted)
- * -Rearming is done by setting the IE bit
- *
- * Small optimisation: Normal code would have been
- * if (irq_reenable)
- * CTRL_REG = (IE | NH);
- * else
- * CTRL_REG = NH;
- * However since IE is BIT0 we can fold the branch
- */
-static void arc_timer_event_ack(unsigned int irq_reenable)
-{
- write_aux_reg(ARC_REG_TIMER0_CTRL, irq_reenable | TIMER_CTRL_NH);
-}
static int arc_clkevent_set_next_event(unsigned long delta,
struct clock_event_device *dev)
@@ -207,10 +191,22 @@ static DEFINE_PER_CPU(struct clock_event_device, arc_clockevent_device) = {
static irqreturn_t timer_irq_handler(int irq, void *dev_id)
{
- struct clock_event_device *clk = this_cpu_ptr(&arc_clockevent_device);
+ /*
+ * Note that generic IRQ core could have passed @evt for @dev_id if
+ * irq_set_chip_and_handler() asked for handle_percpu_devid_irq()
+ */
+ struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
+ int irq_reenable = evt->mode == CLOCK_EVT_MODE_PERIODIC;
+
+ /*
+ * Any write to CTRL reg ACks the interrupt, we rewrite the
+ * Count when [N]ot [H]alted bit.
+ * And re-arm it if perioid by [I]nterrupt [E]nable bit
+ */
+ write_aux_reg(ARC_REG_TIMER0_CTRL, irq_reenable | TIMER_CTRL_NH);
+
+ evt->event_handler(evt);
- arc_timer_event_ack(clk->mode == CLOCK_EVT_MODE_PERIODIC);
- clk->event_handler(clk);
return IRQ_HANDLED;
}
@@ -222,14 +218,14 @@ static struct irqaction arc_timer_irq = {
/*
* Setup the local event timer for @cpu
- * N.B. weak so that some exotic ARC SoCs can completely override it
*/
-void __weak arc_local_timer_setup(unsigned int cpu)
+void arc_local_timer_setup()
{
- struct clock_event_device *clk = &per_cpu(arc_clockevent_device, cpu);
+ struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
+ int cpu = smp_processor_id();
- clk->cpumask = cpumask_of(cpu);
- clockevents_config_and_register(clk, arc_get_core_freq(),
+ evt->cpumask = cpumask_of(cpu);
+ clockevents_config_and_register(evt, arc_get_core_freq(),
0, ARC_TIMER_MAX);
/*
@@ -266,7 +262,7 @@ void __init time_init(void)
clocksource_register_hz(&arc_counter, arc_get_core_freq());
/* sets up the periodic event timer */
- arc_local_timer_setup(smp_processor_id());
+ arc_local_timer_setup();
if (machine_desc->init_time)
machine_desc->init_time();
diff --git a/arch/arc/kernel/troubleshoot.c b/arch/arc/kernel/troubleshoot.c
index 73a7450ee62..1badf9b84b5 100644
--- a/arch/arc/kernel/troubleshoot.c
+++ b/arch/arc/kernel/troubleshoot.c
@@ -86,12 +86,13 @@ static void show_faulting_vma(unsigned long address, char *buf)
unsigned long ino = 0;
dev_t dev = 0;
char *nm = buf;
+ struct mm_struct *active_mm = current->active_mm;
/* can't use print_vma_addr() yet as it doesn't check for
* non-inclusive vma
*/
-
- vma = find_vma(current->active_mm, address);
+ down_read(&active_mm->mmap_sem);
+ vma = find_vma(active_mm, address);
/* check against the find_vma( ) behaviour which returns the next VMA
* if the container VMA is not found
@@ -110,9 +111,10 @@ static void show_faulting_vma(unsigned long address, char *buf)
vma->vm_start < TASK_UNMAPPED_BASE ?
address : address - vma->vm_start,
nm, vma->vm_start, vma->vm_end);
- } else {
+ } else
pr_info(" @No matching VMA found\n");
- }
+
+ up_read(&active_mm->mmap_sem);
}
static void show_ecr_verbose(struct pt_regs *regs)
diff --git a/arch/arc/kernel/vmlinux.lds.S b/arch/arc/kernel/vmlinux.lds.S
index 2555f5886af..dd35bde39f6 100644
--- a/arch/arc/kernel/vmlinux.lds.S
+++ b/arch/arc/kernel/vmlinux.lds.S
@@ -116,7 +116,7 @@ SECTIONS
_edata = .;
- BSS_SECTION(0, 0, 0)
+ BSS_SECTION(4, 4, 4)
#ifdef CONFIG_ARC_DW2_UNWIND
. = ALIGN(PAGE_SIZE);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-13 18:30:31 +0000