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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
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')
-rw-r--r--arch/arc/Kconfig16
-rw-r--r--arch/arc/boot/dts/axs10x_mb.dtsi1
-rw-r--r--arch/arc/include/asm/arcregs.h2
-rw-r--r--arch/arc/include/asm/fpu.h55
-rw-r--r--arch/arc/include/asm/processor.h10
-rw-r--r--arch/arc/include/asm/switch_to.h17
-rw-r--r--arch/arc/include/asm/syscalls.h1
-rw-r--r--arch/arc/include/uapi/asm/unistd.h1
-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
13 files changed, 120 insertions, 40 deletions
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 5f448201955b..ff2a393b635c 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -28,6 +28,7 @@ config ARC
select GENERIC_SMP_IDLE_THREAD
select HAVE_ARCH_KGDB
select HAVE_ARCH_TRACEHOOK
+ select HAVE_COPY_THREAD_TLS
select HAVE_DEBUG_STACKOVERFLOW
select HAVE_DEBUG_KMEMLEAK
select HAVE_FUTEX_CMPXCHG if FUTEX
@@ -350,9 +351,8 @@ config NODES_SHIFT
Accessing memory beyond 1GB (with or w/o PAE) requires 2 memory
zones.
-if ISA_ARCOMPACT
-
config ARC_COMPACT_IRQ_LEVELS
+ depends on ISA_ARCOMPACT
bool "Setup Timer IRQ as high Priority"
# if SMP, LV2 enabled ONLY if ARC implementation has LV2 re-entrancy
depends on !SMP
@@ -360,14 +360,10 @@ config ARC_COMPACT_IRQ_LEVELS
config ARC_FPU_SAVE_RESTORE
bool "Enable FPU state persistence across context switch"
help
- Double Precision Floating Point unit had dedicated regs which
- need to be saved/restored across context-switch.
- Note that ARC FPU is overly simplistic, unlike say x86, which has
- hardware pieces to allow software to conditionally save/restore,
- based on actual usage of FPU by a task. Thus our implemn does
- this for all tasks in system.
-
-endif #ISA_ARCOMPACT
+ ARCompact FPU has internal registers to assist with Double precision
+ Floating Point operations. There are control and stauts registers
+ for floating point exceptions and rounding modes. These are
+ preserved across task context switch when enabled.
config ARC_CANT_LLSC
def_bool n
diff --git a/arch/arc/boot/dts/axs10x_mb.dtsi b/arch/arc/boot/dts/axs10x_mb.dtsi
index f9a5c9ddcae7..1d109b06e7d8 100644
--- a/arch/arc/boot/dts/axs10x_mb.dtsi
+++ b/arch/arc/boot/dts/axs10x_mb.dtsi
@@ -78,6 +78,7 @@
interrupt-names = "macirq";
phy-mode = "rgmii";
snps,pbl = < 32 >;
+ snps,multicast-filter-bins = <256>;
clocks = <&apbclk>;
clock-names = "stmmaceth";
max-speed = <100>;
diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h
index 5134f0baf33c..f7e432448e4b 100644
--- a/arch/arc/include/asm/arcregs.h
+++ b/arch/arc/include/asm/arcregs.h
@@ -39,6 +39,8 @@
#define ARC_REG_CLUSTER_BCR 0xcf
#define ARC_REG_AUX_ICCM 0x208 /* ICCM Base Addr (ARCv2) */
#define ARC_REG_LPB_CTRL 0x488 /* ARCv2 Loop Buffer control */
+#define ARC_REG_FPU_CTRL 0x300
+#define ARC_REG_FPU_STATUS 0x301
/* Common for ARCompact and ARCv2 status register */
#define ARC_REG_STATUS32 0x0A
diff --git a/arch/arc/include/asm/fpu.h b/arch/arc/include/asm/fpu.h
new file mode 100644
index 000000000000..64347250fdf5
--- /dev/null
+++ b/arch/arc/include/asm/fpu.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
+ *
+ */
+
+#ifndef _ASM_ARC_FPU_H
+#define _ASM_ARC_FPU_H
+
+#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
+
+#include <asm/ptrace.h>
+
+#ifdef CONFIG_ISA_ARCOMPACT
+
+/* These DPFP regs need to be saved/restored across ctx-sw */
+struct arc_fpu {
+ struct {
+ unsigned int l, h;
+ } aux_dpfp[2];
+};
+
+#define fpu_init_task(regs)
+
+#else
+
+/*
+ * ARCv2 FPU Control aux register
+ * - bits to enable Traps on Exceptions
+ * - Rounding mode
+ *
+ * ARCv2 FPU Status aux register
+ * - FPU exceptions flags (Inv, Div-by-Zero, overflow, underflow, inexact)
+ * - Flag Write Enable to clear flags explicitly (vs. by fpu instructions
+ * only
+ */
+
+struct arc_fpu {
+ unsigned int ctrl, status;
+};
+
+extern void fpu_init_task(struct pt_regs *regs);
+
+#endif /* !CONFIG_ISA_ARCOMPACT */
+
+extern void fpu_save_restore(struct task_struct *p, struct task_struct *n);
+
+#else /* !CONFIG_ARC_FPU_SAVE_RESTORE */
+
+#define fpu_save_restore(p, n)
+#define fpu_init_task(regs)
+
+#endif /* CONFIG_ARC_FPU_SAVE_RESTORE */
+
+#endif /* _ASM_ARC_FPU_H */
diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h
index 706edeaa5583..ec532d1e0725 100644
--- a/arch/arc/include/asm/processor.h
+++ b/arch/arc/include/asm/processor.h
@@ -14,15 +14,7 @@
#ifndef __ASSEMBLY__
#include <asm/ptrace.h>
-
-#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
-/* These DPFP regs need to be saved/restored across ctx-sw */
-struct arc_fpu {
- struct {
- unsigned int l, h;
- } aux_dpfp[2];
-};
-#endif
+#include <asm/fpu.h>
#ifdef CONFIG_ARC_PLAT_EZNPS
struct eznps_dp {
diff --git a/arch/arc/include/asm/switch_to.h b/arch/arc/include/asm/switch_to.h
index 77f123385e96..aadf65b2b56c 100644
--- a/arch/arc/include/asm/switch_to.h
+++ b/arch/arc/include/asm/switch_to.h
@@ -9,19 +9,7 @@
#ifndef __ASSEMBLY__
#include <linux/sched.h>
-
-#ifdef CONFIG_ARC_FPU_SAVE_RESTORE
-
-extern void fpu_save_restore(struct task_struct *p, struct task_struct *n);
-#define ARC_FPU_PREV(p, n) fpu_save_restore(p, n)
-#define ARC_FPU_NEXT(t)
-
-#else
-
-#define ARC_FPU_PREV(p, n)
-#define ARC_FPU_NEXT(n)
-
-#endif /* !CONFIG_ARC_FPU_SAVE_RESTORE */
+#include <asm/fpu.h>
#ifdef CONFIG_ARC_PLAT_EZNPS
extern void dp_save_restore(struct task_struct *p, struct task_struct *n);
@@ -36,9 +24,8 @@ struct task_struct *__switch_to(struct task_struct *p, struct task_struct *n);
#define switch_to(prev, next, last) \
do { \
ARC_EZNPS_DP_PREV(prev, next); \
- ARC_FPU_PREV(prev, next); \
+ fpu_save_restore(prev, next); \
last = __switch_to(prev, next);\
- ARC_FPU_NEXT(next); \
mb(); \
} while (0)
diff --git a/arch/arc/include/asm/syscalls.h b/arch/arc/include/asm/syscalls.h
index 7ddba13e9b59..c3f4714a4f5c 100644
--- a/arch/arc/include/asm/syscalls.h
+++ b/arch/arc/include/asm/syscalls.h
@@ -11,6 +11,7 @@
#include <linux/types.h>
int sys_clone_wrapper(int, int, int, int, int);
+int sys_clone3_wrapper(void *, size_t);
int sys_cacheflush(uint32_t, uint32_t uint32_t);
int sys_arc_settls(void *);
int sys_arc_gettls(void);
diff --git a/arch/arc/include/uapi/asm/unistd.h b/arch/arc/include/uapi/asm/unistd.h
index 5eafa1115162..fa2713ae6bea 100644
--- a/arch/arc/include/uapi/asm/unistd.h
+++ b/arch/arc/include/uapi/asm/unistd.h
@@ -21,6 +21,7 @@
#define __ARCH_WANT_SET_GET_RLIMIT
#define __ARCH_WANT_SYS_EXECVE
#define __ARCH_WANT_SYS_CLONE
+#define __ARCH_WANT_SYS_CLONE3
#define __ARCH_WANT_SYS_VFORK
#define __ARCH_WANT_SYS_FORK
#define __ARCH_WANT_TIME32_SYSCALLS
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),