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authorLinus Torvalds <torvalds@linux-foundation.org>2020-01-31 11:26:11 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-01-31 11:26:11 -0800
commitb7e573bb4a7a511741f8942b1fb03cfe602ee57f (patch)
treeeba521c86b1e430bae7e2cdd88874198437017b9 /arch/arc/kernel
parenta1084542a8e83b8eb5aaf7e8ccb81b461e7d4ce8 (diff)
parentf45ba2bd6da0dc8000aa7ea7a3858fb51608f766 (diff)
Merge tag 'arc-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta: - Wire up clone3 syscall - ARCv2 FPU state save/restore across context switch - AXS10x platform and misc fixes * tag 'arc-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: ARCv2: fpu: preserve userspace fpu state ARC: fpu: declutter code, move bits out into fpu.h ARC: wireup clone3 syscall ARC: [plat-axs10x]: Add missing multicast filter number to GMAC node ARC: update feature support for jump-labels
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r--arch/arc/kernel/Makefile2
-rw-r--r--arch/arc/kernel/entry.S12
-rw-r--r--arch/arc/kernel/fpu.c29
-rw-r--r--arch/arc/kernel/process.c13
-rw-r--r--arch/arc/kernel/sys.c1
5 files changed, 51 insertions, 6 deletions
diff --git a/arch/arc/kernel/Makefile b/arch/arc/kernel/Makefile
index e784f5396dda..75539670431a 100644
--- a/arch/arc/kernel/Makefile
+++ b/arch/arc/kernel/Makefile
@@ -23,7 +23,9 @@ obj-$(CONFIG_PERF_EVENTS) += perf_event.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_ARC_FPU_SAVE_RESTORE) += fpu.o
+ifdef CONFIG_ISA_ARCOMPACT
CFLAGS_fpu.o += -mdpfp
+endif
ifdef CONFIG_ARC_DW2_UNWIND
CFLAGS_ctx_sw.o += -fno-omit-frame-pointer
diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S
index 1f6bb184a44d..60406ec62eb8 100644
--- a/arch/arc/kernel/entry.S
+++ b/arch/arc/kernel/entry.S
@@ -35,6 +35,18 @@ ENTRY(sys_clone_wrapper)
b .Lret_from_system_call
END(sys_clone_wrapper)
+ENTRY(sys_clone3_wrapper)
+ SAVE_CALLEE_SAVED_USER
+ bl @sys_clone3
+ DISCARD_CALLEE_SAVED_USER
+
+ GET_CURR_THR_INFO_FLAGS r10
+ btst r10, TIF_SYSCALL_TRACE
+ bnz tracesys_exit
+
+ b .Lret_from_system_call
+END(sys_clone3_wrapper)
+
ENTRY(ret_from_fork)
; when the forked child comes here from the __switch_to function
; r0 has the last task pointer.
diff --git a/arch/arc/kernel/fpu.c b/arch/arc/kernel/fpu.c
index 07e22b563fbb..c67c0f0f5f77 100644
--- a/arch/arc/kernel/fpu.c
+++ b/arch/arc/kernel/fpu.c
@@ -6,7 +6,9 @@
*/
#include <linux/sched.h>
-#include <asm/switch_to.h>
+#include <asm/fpu.h>
+
+#ifdef CONFIG_ISA_ARCOMPACT
/*
* To save/restore FPU regs, simplest scheme would use LR/SR insns.
@@ -50,3 +52,28 @@ void fpu_save_restore(struct task_struct *prev, struct task_struct *next)
: "r" (zero), "r" (*(readfrom + 3)), "r" (*(readfrom + 2))
);
}
+
+#else
+
+void fpu_init_task(struct pt_regs *regs)
+{
+ /* default rounding mode */
+ write_aux_reg(ARC_REG_FPU_CTRL, 0x100);
+
+ /* set "Write enable" to allow explicit write to exception flags */
+ write_aux_reg(ARC_REG_FPU_STATUS, 0x80000000);
+}
+
+void fpu_save_restore(struct task_struct *prev, struct task_struct *next)
+{
+ struct arc_fpu *save = &prev->thread.fpu;
+ struct arc_fpu *restore = &next->thread.fpu;
+
+ save->ctrl = read_aux_reg(ARC_REG_FPU_CTRL);
+ save->status = read_aux_reg(ARC_REG_FPU_STATUS);
+
+ write_aux_reg(ARC_REG_FPU_CTRL, restore->ctrl);
+ write_aux_reg(ARC_REG_FPU_STATUS, restore->status);
+}
+
+#endif
diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c
index e1889ce3faf9..315528f04bc1 100644
--- a/arch/arc/kernel/process.c
+++ b/arch/arc/kernel/process.c
@@ -20,6 +20,8 @@
#include <linux/elf.h>
#include <linux/tick.h>
+#include <asm/fpu.h>
+
SYSCALL_DEFINE1(arc_settls, void *, user_tls_data_ptr)
{
task_thread_info(current)->thr_ptr = (unsigned int)user_tls_data_ptr;
@@ -171,9 +173,8 @@ asmlinkage void ret_from_fork(void);
* | user_r25 |
* ------------------ <===== END of PAGE
*/
-int copy_thread(unsigned long clone_flags,
- unsigned long usp, unsigned long kthread_arg,
- struct task_struct *p)
+int copy_thread_tls(unsigned long clone_flags, unsigned long usp,
+ unsigned long kthread_arg, struct task_struct *p, unsigned long tls)
{
struct pt_regs *c_regs; /* child's pt_regs */
unsigned long *childksp; /* to unwind out of __switch_to() */
@@ -231,7 +232,7 @@ int copy_thread(unsigned long clone_flags,
* set task's userland tls data ptr from 4th arg
* clone C-lib call is difft from clone sys-call
*/
- task_thread_info(p)->thr_ptr = regs->r3;
+ task_thread_info(p)->thr_ptr = tls;
} else {
/* Normal fork case: set parent's TLS ptr in child */
task_thread_info(p)->thr_ptr =
@@ -264,7 +265,7 @@ 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)
+void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
{
regs->sp = usp;
regs->ret = pc;
@@ -280,6 +281,8 @@ void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp)
regs->eflags = 0;
#endif
+ fpu_init_task(regs);
+
/* bogus seed values for debugging */
regs->lp_start = 0x10;
regs->lp_end = 0x80;
diff --git a/arch/arc/kernel/sys.c b/arch/arc/kernel/sys.c
index fddecc76efb7..1069446bdc58 100644
--- a/arch/arc/kernel/sys.c
+++ b/arch/arc/kernel/sys.c
@@ -7,6 +7,7 @@
#include <asm/syscalls.h>
#define sys_clone sys_clone_wrapper
+#define sys_clone3 sys_clone3_wrapper
#undef __SYSCALL
#define __SYSCALL(nr, call) [nr] = (call),