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authorLinus Torvalds <torvalds@linux-foundation.org>2018-08-19 19:56:38 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2018-08-19 19:56:38 +0300
commit1009aa1205c2c5e9101437dcadfa195708d863bf (patch)
tree49e76c84522866fae25ba37372aef241b8713c3f /arch/riscv
parent1d0926e99de7b486321e3db924b445531eea5e18 (diff)
parent627672cf431b0379c07cc8d146f907cda6797222 (diff)
downloadlinux-1009aa1205c2c5e9101437dcadfa195708d863bf.tar.xz
Merge tag 'riscv-for-linus-4.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux
Pull RISC-V updates from Palmer Dabbelt: "This contains some major improvements to the RISC-V port, including the necessary interrupt controller and timer support to actually make it to userspace. Support for three devices has been added: - the ISA-mandated timers on RISC-V systems. - the ISA-mandated first-level interrupt controller on RISC-V systems, which is handled as part of our core arch code because it's very small and tightly tied to the ISA. - SiFive's platform-level interrupt controller, which talks to the actual devices. In addition to these new devices, there are a handful of cleanups all over the RISC-V tree: - build fixes for various configurations: * A fix to the vDSO build's makefile so it respects CFLAGS. * The addition of __lshrti3, a libgcc derived function necessary for some 32-bit configurations. * !SMP && PERF_EVENTS - Cleanups to the arch code to remove the remnants of old versions of the drivers that were just properly submitted. * Some dead code from the timer driver, most of which wasn't ever even compiled. * Cleanups of some interrupt #defines, which are now local to the interrupt handling code. - Fixes to ptrace(), which while not being sufficient to fully make GDB work are at least sufficient to get simple GDB tasks to work. - Early printk support via RISC-V's architecturally mandated SBI console device. - A fix to our early debug trap handler to ensure it's always aligned. These patches have all been through a fairly extensive review process, but as this enables a whole pile of functionality (ie, userspace) I'm confident we'll need to submit a few more patches. The only concrete issues I know about are the sys_riscv_flush_icache patches, but as I managed to screw those up on Friday I figured it'd be best to let them bake another week. This tag boots a Fedora root filesystem on QEMU's master branch for me, and before this morning's rebase (from 4.18-rc8 to 4.18) it booted on the HiFive Unleashed. Thanks to Christoph Hellwig and the other guys at WD for getting the new drivers in shape!" * tag 'riscv-for-linus-4.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux: dt-bindings: interrupt-controller: SiFive Plaform Level Interrupt Controller dt-bindings: interrupt-controller: RISC-V local interrupt controller RISC-V: Fix !CONFIG_SMP compilation error irqchip: add a SiFive PLIC driver RISC-V: Add the directive for alignment of stvec's value clocksource: new RISC-V SBI timer driver RISC-V: implement low-level interrupt handling RISC-V: add a definition for the SIE SEIE bit RISC-V: remove INTERRUPT_CAUSE_* defines from asm/irq.h RISC-V: simplify software interrupt / IPI code RISC-V: remove timer leftovers RISC-V: Add early printk support via the SBI console RISC-V: Don't increment sepc after breakpoint. RISC-V: implement __lshrti3. RISC-V: Use KBUILD_CFLAGS instead of KCFLAGS when building the vDSO
Diffstat (limited to 'arch/riscv')
-rw-r--r--arch/riscv/Makefile3
-rw-r--r--arch/riscv/configs/defconfig1
-rw-r--r--arch/riscv/include/asm/csr.h1
-rw-r--r--arch/riscv/include/asm/irq.h5
-rw-r--r--arch/riscv/include/asm/perf_event.h1
-rw-r--r--arch/riscv/include/asm/smp.h6
-rw-r--r--arch/riscv/kernel/entry.S4
-rw-r--r--arch/riscv/kernel/head.S2
-rw-r--r--arch/riscv/kernel/irq.c55
-rw-r--r--arch/riscv/kernel/perf_event.c1
-rw-r--r--arch/riscv/kernel/setup.c27
-rw-r--r--arch/riscv/kernel/smp.c6
-rw-r--r--arch/riscv/kernel/smpboot.c1
-rw-r--r--arch/riscv/kernel/time.c30
-rw-r--r--arch/riscv/kernel/traps.c1
-rw-r--r--arch/riscv/kernel/vdso/Makefile4
-rw-r--r--arch/riscv/lib/Makefile1
-rw-r--r--arch/riscv/lib/tishift.S42
18 files changed, 132 insertions, 59 deletions
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index 2627e4813edf..9ddd88bb30b7 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -25,6 +25,9 @@ ifeq ($(CONFIG_ARCH_RV64I),y)
KBUILD_CFLAGS += -mabi=lp64
KBUILD_AFLAGS += -mabi=lp64
+
+ KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0500, -DCONFIG_ARCH_SUPPORTS_INT128)
+
KBUILD_MARCH = rv64im
LDFLAGS += -melf64lriscv
else
diff --git a/arch/riscv/configs/defconfig b/arch/riscv/configs/defconfig
index 07326466871b..36473d7dbaac 100644
--- a/arch/riscv/configs/defconfig
+++ b/arch/riscv/configs/defconfig
@@ -76,3 +76,4 @@ CONFIG_ROOT_NFS=y
CONFIG_CRYPTO_USER_API_HASH=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
+CONFIG_SIFIVE_PLIC=y
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 421fa3585798..28a0d1cb374c 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -54,6 +54,7 @@
/* Interrupt Enable and Interrupt Pending flags */
#define SIE_SSIE _AC(0x00000002, UL) /* Software Interrupt Enable */
#define SIE_STIE _AC(0x00000020, UL) /* Timer Interrupt Enable */
+#define SIE_SEIE _AC(0x00000200, UL) /* External Interrupt Enable */
#define EXC_INST_MISALIGNED 0
#define EXC_INST_ACCESS 1
diff --git a/arch/riscv/include/asm/irq.h b/arch/riscv/include/asm/irq.h
index 4dee9d4c13c0..996b6fbe17a6 100644
--- a/arch/riscv/include/asm/irq.h
+++ b/arch/riscv/include/asm/irq.h
@@ -17,11 +17,8 @@
#define NR_IRQS 0
-#define INTERRUPT_CAUSE_SOFTWARE 1
-#define INTERRUPT_CAUSE_TIMER 5
-#define INTERRUPT_CAUSE_EXTERNAL 9
-
void riscv_timer_interrupt(void);
+void riscv_software_interrupt(void);
#include <asm-generic/irq.h>
diff --git a/arch/riscv/include/asm/perf_event.h b/arch/riscv/include/asm/perf_event.h
index 0e638a0c3feb..aefbfaa6a781 100644
--- a/arch/riscv/include/asm/perf_event.h
+++ b/arch/riscv/include/asm/perf_event.h
@@ -10,6 +10,7 @@
#include <linux/perf_event.h>
#include <linux/ptrace.h>
+#include <linux/interrupt.h>
#define RISCV_BASE_COUNTERS 2
diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h
index 85e4220839b0..36016845461d 100644
--- a/arch/riscv/include/asm/smp.h
+++ b/arch/riscv/include/asm/smp.h
@@ -25,9 +25,6 @@
#ifdef CONFIG_SMP
/* SMP initialization hook for setup_arch */
-void __init init_clockevent(void);
-
-/* SMP initialization hook for setup_arch */
void __init setup_smp(void);
/* Hook for the generic smp_call_function_many() routine. */
@@ -44,9 +41,6 @@ void arch_send_call_function_single_ipi(int cpu);
*/
#define raw_smp_processor_id() (*((int*)((char*)get_current() + TASK_TI_CPU)))
-/* Interprocessor interrupt handler */
-irqreturn_t handle_ipi(void);
-
#endif /* CONFIG_SMP */
#endif /* _ASM_RISCV_SMP_H */
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 9aaf6c986771..fa2c08e3c05e 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -168,8 +168,8 @@ ENTRY(handle_exception)
/* Handle interrupts */
move a0, sp /* pt_regs */
- REG_L a1, handle_arch_irq
- jr a1
+ move a1, s4 /* scause */
+ tail do_IRQ
1:
/* Exceptions run with interrupts enabled */
csrs sstatus, SR_SIE
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 6e07ed37bbff..c4d2c63f9a29 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -94,6 +94,7 @@ relocate:
or a0, a0, a1
sfence.vma
csrw sptbr, a0
+.align 2
1:
/* Set trap vector to spin forever to help debug */
la a0, .Lsecondary_park
@@ -143,6 +144,7 @@ relocate:
tail smp_callin
#endif
+.align 2
.Lsecondary_park:
/* We lack SMP support or have too many harts, so park this hart */
wfi
diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c
index 7bcdaed15703..0cfac48a1272 100644
--- a/arch/riscv/kernel/irq.c
+++ b/arch/riscv/kernel/irq.c
@@ -1,21 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2012 Regents of the University of California
* Copyright (C) 2017 SiFive
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, version 2.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * Copyright (C) 2018 Christoph Hellwig
*/
#include <linux/interrupt.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
+/*
+ * Possible interrupt causes:
+ */
+#define INTERRUPT_CAUSE_SOFTWARE 1
+#define INTERRUPT_CAUSE_TIMER 5
+#define INTERRUPT_CAUSE_EXTERNAL 9
+
+/*
+ * The high order bit of the trap cause register is always set for
+ * interrupts, which allows us to differentiate them from exceptions
+ * quickly. The INTERRUPT_CAUSE_* macros don't contain that bit, so we
+ * need to mask it off.
+ */
+#define INTERRUPT_CAUSE_FLAG (1UL << (__riscv_xlen - 1))
+
+asmlinkage void __irq_entry do_IRQ(struct pt_regs *regs, unsigned long cause)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ irq_enter();
+ switch (cause & ~INTERRUPT_CAUSE_FLAG) {
+ case INTERRUPT_CAUSE_TIMER:
+ riscv_timer_interrupt();
+ break;
+#ifdef CONFIG_SMP
+ case INTERRUPT_CAUSE_SOFTWARE:
+ /*
+ * We only use software interrupts to pass IPIs, so if a non-SMP
+ * system gets one, then we don't know what to do.
+ */
+ riscv_software_interrupt();
+ break;
+#endif
+ case INTERRUPT_CAUSE_EXTERNAL:
+ handle_arch_irq(regs);
+ break;
+ default:
+ panic("unexpected interrupt cause");
+ }
+ irq_exit();
+
+ set_irq_regs(old_regs);
+}
+
void __init init_IRQ(void)
{
irqchip_init();
diff --git a/arch/riscv/kernel/perf_event.c b/arch/riscv/kernel/perf_event.c
index b0e10c4e9f77..a243fae1c1db 100644
--- a/arch/riscv/kernel/perf_event.c
+++ b/arch/riscv/kernel/perf_event.c
@@ -27,7 +27,6 @@
#include <linux/mutex.h>
#include <linux/bitmap.h>
#include <linux/irq.h>
-#include <linux/interrupt.h>
#include <linux/perf_event.h>
#include <linux/atomic.h>
#include <linux/of.h>
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index f0d2070866d4..db20dc630e7e 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -39,6 +39,27 @@
#include <asm/tlbflush.h>
#include <asm/thread_info.h>
+#ifdef CONFIG_EARLY_PRINTK
+static void sbi_console_write(struct console *co, const char *buf,
+ unsigned int n)
+{
+ int i;
+
+ for (i = 0; i < n; ++i) {
+ if (buf[i] == '\n')
+ sbi_console_putchar('\r');
+ sbi_console_putchar(buf[i]);
+ }
+}
+
+struct console riscv_sbi_early_console_dev __initdata = {
+ .name = "early",
+ .write = sbi_console_write,
+ .flags = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
+ .index = -1
+};
+#endif
+
#ifdef CONFIG_DUMMY_CONSOLE
struct screen_info screen_info = {
.orig_video_lines = 30,
@@ -195,6 +216,12 @@ static void __init setup_bootmem(void)
void __init setup_arch(char **cmdline_p)
{
+#if defined(CONFIG_EARLY_PRINTK)
+ if (likely(early_console == NULL)) {
+ early_console = &riscv_sbi_early_console_dev;
+ register_console(early_console);
+ }
+#endif
*cmdline_p = boot_command_line;
parse_early_param();
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 6d3962435720..906fe21ea21b 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -45,7 +45,7 @@ int setup_profiling_timer(unsigned int multiplier)
return -EINVAL;
}
-irqreturn_t handle_ipi(void)
+void riscv_software_interrupt(void)
{
unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
@@ -60,7 +60,7 @@ irqreturn_t handle_ipi(void)
ops = xchg(pending_ipis, 0);
if (ops == 0)
- return IRQ_HANDLED;
+ return;
if (ops & (1 << IPI_RESCHEDULE))
scheduler_ipi();
@@ -73,8 +73,6 @@ irqreturn_t handle_ipi(void)
/* Order data access and bit testing. */
mb();
}
-
- return IRQ_HANDLED;
}
static void
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index f741458c5a3f..56abab6a9812 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -104,7 +104,6 @@ asmlinkage void __init smp_callin(void)
current->active_mm = mm;
trap_init();
- init_clockevent();
notify_cpu_starting(smp_processor_id());
set_cpu_online(smp_processor_id(), 1);
local_flush_tlb_all();
diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
index 2463fcca719e..1911c8f6b8a6 100644
--- a/arch/riscv/kernel/time.c
+++ b/arch/riscv/kernel/time.c
@@ -13,38 +13,11 @@
*/
#include <linux/clocksource.h>
-#include <linux/clockchips.h>
#include <linux/delay.h>
-
-#ifdef CONFIG_RISCV_TIMER
-#include <linux/timer_riscv.h>
-#endif
-
#include <asm/sbi.h>
unsigned long riscv_timebase;
-DECLARE_PER_CPU(struct clock_event_device, riscv_clock_event);
-
-void riscv_timer_interrupt(void)
-{
-#ifdef CONFIG_RISCV_TIMER
- /*
- * FIXME: This needs to be cleaned up along with the rest of the IRQ
- * handling cleanup. See irq.c for more details.
- */
- struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
-
- evdev->event_handler(evdev);
-#endif
-}
-
-void __init init_clockevent(void)
-{
- timer_probe();
- csr_set(sie, SIE_STIE);
-}
-
void __init time_init(void)
{
struct device_node *cpu;
@@ -56,6 +29,5 @@ void __init time_init(void)
riscv_timebase = prop;
lpj_fine = riscv_timebase / HZ;
-
- init_clockevent();
+ timer_probe();
}
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 81a1952015a6..24a9333dda2c 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -138,7 +138,6 @@ asmlinkage void do_trap_break(struct pt_regs *regs)
#endif /* CONFIG_GENERIC_BUG */
force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)(regs->sepc), current);
- regs->sepc += 0x4;
}
#ifdef CONFIG_GENERIC_BUG
diff --git a/arch/riscv/kernel/vdso/Makefile b/arch/riscv/kernel/vdso/Makefile
index f6561b783b61..eed1c137f618 100644
--- a/arch/riscv/kernel/vdso/Makefile
+++ b/arch/riscv/kernel/vdso/Makefile
@@ -52,8 +52,8 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
# Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions.
# Make sure only to export the intended __vdso_xxx symbol offsets.
quiet_cmd_vdsold = VDSOLD $@
- cmd_vdsold = $(CC) $(KCFLAGS) $(call cc-option, -no-pie) -nostdlib $(SYSCFLAGS_$(@F)) \
- -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp -lgcc && \
+ cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \
+ -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \
$(CROSS_COMPILE)objcopy \
$(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@
diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
index 596c2ca40d63..445ec84f9a47 100644
--- a/arch/riscv/lib/Makefile
+++ b/arch/riscv/lib/Makefile
@@ -2,5 +2,6 @@ lib-y += delay.o
lib-y += memcpy.o
lib-y += memset.o
lib-y += uaccess.o
+lib-y += tishift.o
lib-$(CONFIG_32BIT) += udivdi3.o
diff --git a/arch/riscv/lib/tishift.S b/arch/riscv/lib/tishift.S
new file mode 100644
index 000000000000..69abb1277234
--- /dev/null
+++ b/arch/riscv/lib/tishift.S
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2018 Free Software Foundation, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+ .globl __lshrti3
+__lshrti3:
+ beqz a2, .L1
+ li a5,64
+ sub a5,a5,a2
+ addi sp,sp,-16
+ sext.w a4,a5
+ blez a5, .L2
+ sext.w a2,a2
+ sll a4,a1,a4
+ srl a0,a0,a2
+ srl a1,a1,a2
+ or a0,a0,a4
+ sd a1,8(sp)
+ sd a0,0(sp)
+ ld a0,0(sp)
+ ld a1,8(sp)
+ addi sp,sp,16
+ ret
+.L1:
+ ret
+.L2:
+ negw a4,a4
+ srl a1,a1,a4
+ sd a1,0(sp)
+ sd zero,8(sp)
+ ld a0,0(sp)
+ ld a1,8(sp)
+ addi sp,sp,16
+ ret