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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-17 01:29:34 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-17 01:29:34 +0300
commit58d4fafd0b4c36838077a5d7b17df537b7226f1c (patch)
tree1b6b824c5ca4d1a5ff72219c18ee16dd23f90c4d /drivers
parentdbcda58ad98936079c48728c12c27a2f333fb484 (diff)
parent9ce06497c2722a0f9109e4cc3ce35b7a69617886 (diff)
downloadlinux-58d4fafd0b4c36838077a5d7b17df537b7226f1c.tar.xz
Merge tag 'riscv/for-v5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Paul Walmsley: "Add the following new features: - Generic CPU topology description support for DT-based platforms, including ARM64, ARM and RISC-V. - Sparsemem support - Perf callchain support - SiFive PLIC irqchip modifications, in preparation for M-mode Linux and clean up the code base: - Clean up chip-specific register (CSR) manipulation code, IPIs, TLB flushing, and the RISC-V CPU-local timer code - Kbuild cleanup from one of the Kbuild maintainers" [ The CPU topology parts came in through the arm64 tree with a shared branch - Linus ] * tag 'riscv/for-v5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: irqchip/sifive-plic: set max threshold for ignored handlers riscv: move the TLB flush logic out of line riscv: don't use the rdtime(h) pseudo-instructions riscv: cleanup riscv_cpuid_to_hartid_mask riscv: optimize send_ipi_single riscv: cleanup send_ipi_mask riscv: refactor the IPI code riscv: Add support for libdw riscv: Add support for perf registers sampling riscv: Add perf callchain support riscv: add arch/riscv/Kbuild RISC-V: Implement sparsemem riscv: Using CSR numbers to access CSRs
Diffstat (limited to 'drivers')
-rw-r--r--drivers/clocksource/timer-riscv.c17
-rw-r--r--drivers/irqchip/irq-sifive-plic.c12
2 files changed, 14 insertions, 15 deletions
diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index 09e031176bc6..470c7ef02ea4 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -2,6 +2,10 @@
/*
* Copyright (C) 2012 Regents of the University of California
* Copyright (C) 2017 SiFive
+ *
+ * All RISC-V systems have a timer attached to every hart. These timers can be
+ * read from the "time" and "timeh" CSRs, and can use the SBI to setup
+ * events.
*/
#include <linux/clocksource.h>
#include <linux/clockchips.h>
@@ -12,19 +16,6 @@
#include <asm/smp.h>
#include <asm/sbi.h>
-/*
- * All RISC-V systems have a timer attached to every hart. These timers can be
- * read by the 'rdcycle' pseudo instruction, and can use the SBI to setup
- * events. In order to abstract the architecture-specific timer reading and
- * setting functions away from the clock event insertion code, we provide
- * function pointers to the clockevent subsystem that perform two basic
- * operations: rdtime() reads the timer on the current CPU, and
- * next_event(delta) sets the next timer event to 'delta' cycles in the future.
- * As the timers are inherently a per-cpu resource, these callbacks perform
- * operations on the current hart. There is guaranteed to be exactly one timer
- * per hart on all RISC-V systems.
- */
-
static int riscv_clock_next_event(unsigned long delta,
struct clock_event_device *ce)
{
diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index cf755964f2f8..c72c036aea76 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -244,6 +244,7 @@ static int __init plic_init(struct device_node *node,
struct plic_handler *handler;
irq_hw_number_t hwirq;
int cpu, hartid;
+ u32 threshold = 0;
if (of_irq_parse_one(node, i, &parent)) {
pr_err("failed to parse parent for context %d.\n", i);
@@ -266,10 +267,16 @@ static int __init plic_init(struct device_node *node,
continue;
}
+ /*
+ * When running in M-mode we need to ignore the S-mode handler.
+ * Here we assume it always comes later, but that might be a
+ * little fragile.
+ */
handler = per_cpu_ptr(&plic_handlers, cpu);
if (handler->present) {
pr_warn("handler already present for context %d.\n", i);
- continue;
+ threshold = 0xffffffff;
+ goto done;
}
handler->present = true;
@@ -279,8 +286,9 @@ static int __init plic_init(struct device_node *node,
handler->enable_base =
plic_regs + ENABLE_BASE + i * ENABLE_PER_HART;
+done:
/* priority must be > threshold to trigger an interrupt */
- writel(0, handler->hart_base + CONTEXT_THRESHOLD);
+ writel(threshold, handler->hart_base + CONTEXT_THRESHOLD);
for (hwirq = 1; hwirq <= nr_irqs; hwirq++)
plic_toggle(handler, hwirq, 0);
nr_handlers++;