Merge tag 'riscv/for-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Paul Walmsley:
"A few minor RISC-V updates for v5.3-rc4:
- Remove __udivdi3() from the 32-bit Linux port, converting the only
upstream user to use do_div(), per Linux policy
- Convert the RISC-V standard clocksource away from per-cpu data
structures, since only one is used by Linux, even on a multi-CPU
system
- A set of DT binding updates that remove an obsolete text binding in
favor of a YAML binding, fix a bogus compatible string in the
schema (thus fixing a "make dtbs_check" warning), and clarifies the
future values expected in one of the RISC-V CPU properties"
* tag 'riscv/for-v5.3-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
dt-bindings: riscv: fix the schema compatible string for the HiFive Unleashed board
dt-bindings: riscv: remove obsolete cpus.txt
RISC-V: Remove udivdi3
riscv: delay: use do_div() instead of __udivdi3()
dt-bindings: Update the riscv,isa string description
RISC-V: Remove per cpu clocksource
diff --git a/Documentation/devicetree/bindings/riscv/cpus.txt b/Documentation/devicetree/bindings/riscv/cpus.txt
deleted file mode 100644
index adf7b7a..0000000
--- a/Documentation/devicetree/bindings/riscv/cpus.txt
+++ /dev/null
@@ -1,162 +0,0 @@
-===================
-RISC-V CPU Bindings
-===================
-
-The device tree allows to describe the layout of CPUs in a system through
-the "cpus" node, which in turn contains a number of subnodes (ie "cpu")
-defining properties for every cpu.
-
-Bindings for CPU nodes follow the Devicetree Specification, available from:
-
-https://www.devicetree.org/specifications/
-
-with updates for 32-bit and 64-bit RISC-V systems provided in this document.
-
-===========
-Terminology
-===========
-
-This document uses some terminology common to the RISC-V community that is not
-widely used, the definitions of which are listed here:
-
-* hart: A hardware execution context, which contains all the state mandated by
- the RISC-V ISA: a PC and some registers. This terminology is designed to
- disambiguate software's view of execution contexts from any particular
- microarchitectural implementation strategy. For example, my Intel laptop is
- described as having one socket with two cores, each of which has two hyper
- threads. Therefore this system has four harts.
-
-=====================================
-cpus and cpu node bindings definition
-=====================================
-
-The RISC-V architecture, in accordance with the Devicetree Specification,
-requires the cpus and cpu nodes to be present and contain the properties
-described below.
-
-- cpus node
-
- Description: Container of cpu nodes
-
- The node name must be "cpus".
-
- A cpus node must define the following properties:
-
- - #address-cells
- Usage: required
- Value type: <u32>
- Definition: must be set to 1
- - #size-cells
- Usage: required
- Value type: <u32>
- Definition: must be set to 0
-
-- cpu node
-
- Description: Describes a hart context
-
- PROPERTIES
-
- - device_type
- Usage: required
- Value type: <string>
- Definition: must be "cpu"
- - reg
- Usage: required
- Value type: <u32>
- Definition: The hart ID of this CPU node
- - compatible:
- Usage: required
- Value type: <stringlist>
- Definition: must contain "riscv", may contain one of
- "sifive,rocket0"
- - mmu-type:
- Usage: optional
- Value type: <string>
- Definition: Specifies the CPU's MMU type. Possible values are
- "riscv,sv32"
- "riscv,sv39"
- "riscv,sv48"
- - riscv,isa:
- Usage: required
- Value type: <string>
- Definition: Contains the RISC-V ISA string of this hart. These
- ISA strings are defined by the RISC-V ISA manual.
-
-Example: SiFive Freedom U540G Development Kit
----------------------------------------------
-
-This system contains two harts: a hart marked as disabled that's used for
-low-level system tasks and should be ignored by Linux, and a second hart that
-Linux is allowed to run on.
-
- cpus {
- #address-cells = <1>;
- #size-cells = <0>;
- timebase-frequency = <1000000>;
- cpu@0 {
- clock-frequency = <1600000000>;
- compatible = "sifive,rocket0", "riscv";
- device_type = "cpu";
- i-cache-block-size = <64>;
- i-cache-sets = <128>;
- i-cache-size = <16384>;
- next-level-cache = <&L15 &L0>;
- reg = <0>;
- riscv,isa = "rv64imac";
- status = "disabled";
- L10: interrupt-controller {
- #interrupt-cells = <1>;
- compatible = "riscv,cpu-intc";
- interrupt-controller;
- };
- };
- cpu@1 {
- clock-frequency = <1600000000>;
- compatible = "sifive,rocket0", "riscv";
- d-cache-block-size = <64>;
- d-cache-sets = <64>;
- d-cache-size = <32768>;
- d-tlb-sets = <1>;
- d-tlb-size = <32>;
- device_type = "cpu";
- i-cache-block-size = <64>;
- i-cache-sets = <64>;
- i-cache-size = <32768>;
- i-tlb-sets = <1>;
- i-tlb-size = <32>;
- mmu-type = "riscv,sv39";
- next-level-cache = <&L15 &L0>;
- reg = <1>;
- riscv,isa = "rv64imafdc";
- status = "okay";
- tlb-split;
- L13: interrupt-controller {
- #interrupt-cells = <1>;
- compatible = "riscv,cpu-intc";
- interrupt-controller;
- };
- };
- };
-
-Example: Spike ISA Simulator with 1 Hart
-----------------------------------------
-
-This device tree matches the Spike ISA golden model as run with `spike -p1`.
-
- cpus {
- cpu@0 {
- device_type = "cpu";
- reg = <0x00000000>;
- status = "okay";
- compatible = "riscv";
- riscv,isa = "rv64imafdc";
- mmu-type = "riscv,sv48";
- clock-frequency = <0x3b9aca00>;
- interrupt-controller {
- #interrupt-cells = <0x00000001>;
- interrupt-controller;
- compatible = "riscv,cpu-intc";
- }
- }
- }
diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
index c899111..b261a30 100644
--- a/Documentation/devicetree/bindings/riscv/cpus.yaml
+++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
@@ -10,6 +10,18 @@
- Paul Walmsley <paul.walmsley@sifive.com>
- Palmer Dabbelt <palmer@sifive.com>
+description: |
+ This document uses some terminology common to the RISC-V community
+ that is not widely used, the definitions of which are listed here:
+
+ hart: A hardware execution context, which contains all the state
+ mandated by the RISC-V ISA: a PC and some registers. This
+ terminology is designed to disambiguate software's view of execution
+ contexts from any particular microarchitectural implementation
+ strategy. For example, an Intel laptop containing one socket with
+ two cores, each of which has two hyperthreads, could be described as
+ having four harts.
+
properties:
compatible:
items:
@@ -50,6 +62,10 @@
User-Level ISA document, available from
https://riscv.org/specifications/
+ While the isa strings in ISA specification are case
+ insensitive, letters in the riscv,isa string must be all
+ lowercase to simplify parsing.
+
timebase-frequency:
type: integer
minimum: 1
diff --git a/Documentation/devicetree/bindings/riscv/sifive.yaml b/Documentation/devicetree/bindings/riscv/sifive.yaml
index 9d17dc2..3ab5327 100644
--- a/Documentation/devicetree/bindings/riscv/sifive.yaml
+++ b/Documentation/devicetree/bindings/riscv/sifive.yaml
@@ -19,7 +19,7 @@
compatible:
items:
- enum:
- - sifive,freedom-unleashed-a00
+ - sifive,hifive-unleashed-a00
- const: sifive,fu540-c000
- const: sifive,fu540
...
diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile
index 8e364eb..267feaa 100644
--- a/arch/riscv/lib/Makefile
+++ b/arch/riscv/lib/Makefile
@@ -5,5 +5,3 @@
lib-y += uaccess.o
lib-$(CONFIG_64BIT) += tishift.o
-
-lib-$(CONFIG_32BIT) += udivdi3.o
diff --git a/arch/riscv/lib/delay.c b/arch/riscv/lib/delay.c
index 87ff89e..f51c9a0 100644
--- a/arch/riscv/lib/delay.c
+++ b/arch/riscv/lib/delay.c
@@ -81,9 +81,13 @@
void udelay(unsigned long usecs)
{
u64 ucycles = (u64)usecs * lpj_fine * UDELAY_MULT;
+ u64 n;
if (unlikely(usecs > MAX_UDELAY_US)) {
- __delay((u64)usecs * riscv_timebase / 1000000ULL);
+ n = (u64)usecs * riscv_timebase;
+ do_div(n, 1000000);
+
+ __delay(n);
return;
}
diff --git a/arch/riscv/lib/udivdi3.S b/arch/riscv/lib/udivdi3.S
deleted file mode 100644
index 3f07476..0000000
--- a/arch/riscv/lib/udivdi3.S
+++ /dev/null
@@ -1,32 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2016-2017 Free Software Foundation, Inc.
- */
-
-#include <linux/linkage.h>
-
-ENTRY(__udivdi3)
- mv a2, a1
- mv a1, a0
- li a0, -1
- beqz a2, .L5
- li a3, 1
- bgeu a2, a1, .L2
-.L1:
- blez a2, .L2
- slli a2, a2, 1
- slli a3, a3, 1
- bgtu a1, a2, .L1
-.L2:
- li a0, 0
-.L3:
- bltu a1, a2, .L4
- sub a1, a1, a2
- or a0, a0, a3
-.L4:
- srli a3, a3, 1
- srli a2, a2, 1
- bnez a3, .L3
-.L5:
- ret
-ENDPROC(__udivdi3)
diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c
index 5e6038f..09e0311 100644
--- a/drivers/clocksource/timer-riscv.c
+++ b/drivers/clocksource/timer-riscv.c
@@ -55,7 +55,7 @@
return get_cycles64();
}
-static DEFINE_PER_CPU(struct clocksource, riscv_clocksource) = {
+static struct clocksource riscv_clocksource = {
.name = "riscv_clocksource",
.rating = 300,
.mask = CLOCKSOURCE_MASK(64),
@@ -92,7 +92,6 @@
static int __init riscv_timer_init_dt(struct device_node *n)
{
int cpuid, hartid, error;
- struct clocksource *cs;
hartid = riscv_of_processor_hartid(n);
if (hartid < 0) {
@@ -112,8 +111,7 @@
pr_info("%s: Registering clocksource cpuid [%d] hartid [%d]\n",
__func__, cpuid, hartid);
- cs = per_cpu_ptr(&riscv_clocksource, cpuid);
- error = clocksource_register_hz(cs, riscv_timebase);
+ error = clocksource_register_hz(&riscv_clocksource, riscv_timebase);
if (error) {
pr_err("RISCV timer register failed [%d] for cpu = [%d]\n",
error, cpuid);
