Merge tag 'riscv/for-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Paul Walmsley:
 "New features:
   - SECCOMP support
   - nommu support
   - SBI-less system support
   - M-Mode support
   - TLB flush optimizations

  Other improvements:
   - Pass the complete RISC-V ISA string supported by the CPU cores to
     userspace, rather than redacting parts of it in the kernel
   - Add platform DMA IP block data to the HiFive Unleashed board DT
     file
   - Add Makefile support for BZ2, LZ4, LZMA, LZO kernel image
     compression formats, in line with other architectures

  Cleanups:
   - Remove unnecessary PTE_PARENT_SIZE macro
   - Standardize include guard naming across arch/riscv"

* tag 'riscv/for-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (22 commits)
  riscv: provide a flat image loader
  riscv: add nommu support
  riscv: clear the instruction cache and all registers when booting
  riscv: read the hart ID from mhartid on boot
  riscv: provide native clint access for M-mode
  riscv: dts: add support for PDMA device of HiFive Unleashed Rev A00
  riscv: add support for MMIO access to the timer registers
  riscv: implement remote sfence.i using IPIs
  riscv: cleanup the default power off implementation
  riscv: poison SBI calls for M-mode
  riscv: don't allow selecting SBI based drivers for M-mode
  RISC-V: Add multiple compression image format.
  riscv: clean up the macro format in each header file
  riscv: Use PMD_SIZE to replace PTE_PARENT_SIZE
  riscv: abstract out CSR names for supervisor vs machine mode
  riscv: separate MMIO functions into their own header file
  riscv: enter WFI in default_power_off() if SBI does not shutdown
  RISC-V: Issue a tlb page flush if possible
  RISC-V: Issue a local tlbflush if possible.
  RISC-V: Do not invoke SBI call if cpumask is empty
  ...

1 files changed, 23 insertions, 8 deletions

diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index 470c7ef02ea4..4e54856ce2a5 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -3,9 +3,9 @@
  * 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.
+ * All RISC-V systems have a timer attached to every hart.  These timers can
+ * either be read from the "time" and "timeh" CSRs, and can use the SBI to
+ * setup events, or directly accessed using MMIO registers.
  */
 #include <linux/clocksource.h>
 #include <linux/clockchips.h>
@@ -13,14 +13,29 @@
 #include <linux/delay.h>
 #include <linux/irq.h>
 #include <linux/sched_clock.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
 #include <asm/smp.h>
 #include <asm/sbi.h>
 
+u64 __iomem *riscv_time_cmp;
+u64 __iomem *riscv_time_val;
+
+static inline void mmio_set_timer(u64 val)
+{
+	void __iomem *r;
+
+	r = riscv_time_cmp + cpuid_to_hartid_map(smp_processor_id());
+	writeq_relaxed(val, r);
+}
+
 static int riscv_clock_next_event(unsigned long delta,
 		struct clock_event_device *ce)
 {
-	csr_set(sie, SIE_STIE);
-	sbi_set_timer(get_cycles64() + delta);
+	csr_set(CSR_IE, IE_TIE);
+	if (IS_ENABLED(CONFIG_RISCV_SBI))
+		sbi_set_timer(get_cycles64() + delta);
+	else
+		mmio_set_timer(get_cycles64() + delta);
 	return 0;
 }
 
@@ -61,13 +76,13 @@ static int riscv_timer_starting_cpu(unsigned int cpu)
 	ce->cpumask = cpumask_of(cpu);
 	clockevents_config_and_register(ce, riscv_timebase, 100, 0x7fffffff);
 
-	csr_set(sie, SIE_STIE);
+	csr_set(CSR_IE, IE_TIE);
 	return 0;
 }
 
 static int riscv_timer_dying_cpu(unsigned int cpu)
 {
-	csr_clear(sie, SIE_STIE);
+	csr_clear(CSR_IE, IE_TIE);
 	return 0;
 }
 
@@ -76,7 +91,7 @@ void riscv_timer_interrupt(void)
 {
 	struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
 
-	csr_clear(sie, SIE_STIE);
+	csr_clear(CSR_IE, IE_TIE);
 	evdev->event_handler(evdev);
 }