From 713203e303ca9f75be8c729b533bf1559e442f6e Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Fri, 2 Aug 2019 21:27:20 -0700 Subject: RISC-V: Remove per cpu clocksource There is only one clocksource in RISC-V. The boot cpu initializes that clocksource. No need to keep a percpu data structure. Signed-off-by: Atish Patra Signed-off-by: Paul Walmsley Acked-by: Daniel Lezcano --- drivers/clocksource/timer-riscv.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c index 5e6038fbf115..09e031176bc6 100644 --- a/drivers/clocksource/timer-riscv.c +++ b/drivers/clocksource/timer-riscv.c @@ -55,7 +55,7 @@ static u64 riscv_sched_clock(void) 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 @@ void riscv_timer_interrupt(void) 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 @@ static int __init riscv_timer_init_dt(struct device_node *n) 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); -- cgit v1.2.3 From 94ed3fde38c7c1347cd82b945553905cfd992ab9 Mon Sep 17 00:00:00 2001 From: Atish Patra Date: Fri, 2 Aug 2019 21:27:23 -0700 Subject: dt-bindings: Update the riscv,isa string description Since the RISC-V specification states that ISA description strings are case-insensitive, there's no functional difference between mixed-case, upper-case, and lower-case ISA strings. Thus, to simplify parsing, specify that the letters present in "riscv,isa" must be all lowercase. Suggested-by: Paul Walmsley Signed-off-by: Atish Patra Signed-off-by: Paul Walmsley --- Documentation/devicetree/bindings/riscv/cpus.yaml | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml index c899111aa5e3..9d3fe6aada2b 100644 --- a/Documentation/devicetree/bindings/riscv/cpus.yaml +++ b/Documentation/devicetree/bindings/riscv/cpus.yaml @@ -50,6 +50,10 @@ properties: 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 -- cgit v1.2.3 From 66cc016ab7c780d53450fd1648010da02ddf2770 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Tue, 6 Aug 2019 18:28:33 -0700 Subject: riscv: delay: use do_div() instead of __udivdi3() In preparation for removing __udivdi3() from the RISC-V architecture-specific files, convert its one user to use do_div(). This avoids breaking the RV32 build after __udivdi3() is removed. This second version removes the assignment of the remainder to an unused temporary variable. Thanks to Nicolas Pitre for the suggestion. Signed-off-by: Paul Walmsley Cc: Nicolas Pitre --- arch/riscv/lib/delay.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/riscv/lib/delay.c b/arch/riscv/lib/delay.c index 87ff89e88f2c..f51c9a03bca1 100644 --- a/arch/riscv/lib/delay.c +++ b/arch/riscv/lib/delay.c @@ -81,9 +81,13 @@ EXPORT_SYMBOL(__delay); 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; } -- cgit v1.2.3 From 81a48ee417387bef9cb720ca75980ee11ae9c901 Mon Sep 17 00:00:00 2001 From: Palmer Dabbelt Date: Tue, 6 Aug 2019 17:05:08 -0700 Subject: RISC-V: Remove udivdi3 This should never have landed in the first place: it was added as part of 64-bit divide support for 32-bit systems, but the kernel doesn't allow this sort of division. I must have forgotten to remove it. This patch removes the support. Since this routine only worked on 64-bit platforms but was only built on 32-bit platforms, it's essentially just nonsense anyway. Signed-off-by: Palmer Dabbelt Acked-by: Nicolas Pitre Link: https://lore.kernel.org/linux-riscv/nycvar.YSQ.7.76.1908061413360.19480@knanqh.ubzr/T/#t Reported-by: Eric Lin Signed-off-by: Paul Walmsley --- arch/riscv/lib/Makefile | 2 -- arch/riscv/lib/udivdi3.S | 32 -------------------------------- 2 files changed, 34 deletions(-) delete mode 100644 arch/riscv/lib/udivdi3.S diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index 8e364ebf37de..267feaa10f6a 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -5,5 +5,3 @@ lib-y += memset.o lib-y += uaccess.o lib-$(CONFIG_64BIT) += tishift.o - -lib-$(CONFIG_32BIT) += udivdi3.o diff --git a/arch/riscv/lib/udivdi3.S b/arch/riscv/lib/udivdi3.S deleted file mode 100644 index 3f07476a91a9..000000000000 --- 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 - -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) -- cgit v1.2.3 From 8e5e72e3314021a3d166c1d19a991a0870568856 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Thu, 8 Aug 2019 14:46:58 -0700 Subject: dt-bindings: riscv: remove obsolete cpus.txt Remove the now-obsolete riscv/cpus.txt DT binding document, since we are using YAML binding documentation instead. While doing so, transfer the explanatory text about 'harts' (with some edits) into the YAML file, at Rob's request. Link: https://lore.kernel.org/linux-riscv/CAL_JsqJs6MtvmuyAknsUxQymbmoV=G+=JfS1PQj9kNHV7fjC9g@mail.gmail.com/ Signed-off-by: Paul Walmsley Cc: Rob Herring Reviewed-by: Rob Herring --- Documentation/devicetree/bindings/riscv/cpus.txt | 162 ---------------------- Documentation/devicetree/bindings/riscv/cpus.yaml | 12 ++ 2 files changed, 12 insertions(+), 162 deletions(-) delete mode 100644 Documentation/devicetree/bindings/riscv/cpus.txt diff --git a/Documentation/devicetree/bindings/riscv/cpus.txt b/Documentation/devicetree/bindings/riscv/cpus.txt deleted file mode 100644 index adf7b7af5dc3..000000000000 --- 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: - Definition: must be set to 1 - - #size-cells - Usage: required - Value type: - Definition: must be set to 0 - -- cpu node - - Description: Describes a hart context - - PROPERTIES - - - device_type - Usage: required - Value type: - Definition: must be "cpu" - - reg - Usage: required - Value type: - Definition: The hart ID of this CPU node - - compatible: - Usage: required - Value type: - Definition: must contain "riscv", may contain one of - "sifive,rocket0" - - mmu-type: - Usage: optional - Value type: - Definition: Specifies the CPU's MMU type. Possible values are - "riscv,sv32" - "riscv,sv39" - "riscv,sv48" - - riscv,isa: - Usage: required - Value type: - 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 9d3fe6aada2b..b261a3015f84 100644 --- a/Documentation/devicetree/bindings/riscv/cpus.yaml +++ b/Documentation/devicetree/bindings/riscv/cpus.yaml @@ -10,6 +10,18 @@ maintainers: - Paul Walmsley - Palmer Dabbelt +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: -- cgit v1.2.3 From b390e0bfd2996f1215231395f4e25a4c011eeaf9 Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Thu, 8 Aug 2019 15:36:44 -0700 Subject: dt-bindings: riscv: fix the schema compatible string for the HiFive Unleashed board The YAML binding document for SiFive boards has an incorrect compatible string for the HiFive Unleashed board. Change it to match the name of the board on the SiFive web site: https://www.sifive.com/boards/hifive-unleashed which also matches the contents of the board DT data file: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/riscv/boot/dts/sifive/hifive-unleashed-a00.dts#n13 Signed-off-by: Paul Walmsley Acked-by: Rob Herring --- Documentation/devicetree/bindings/riscv/sifive.yaml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/riscv/sifive.yaml b/Documentation/devicetree/bindings/riscv/sifive.yaml index 9d17dc2f3f84..3ab532713dc1 100644 --- a/Documentation/devicetree/bindings/riscv/sifive.yaml +++ b/Documentation/devicetree/bindings/riscv/sifive.yaml @@ -19,7 +19,7 @@ properties: compatible: items: - enum: - - sifive,freedom-unleashed-a00 + - sifive,hifive-unleashed-a00 - const: sifive,fu540-c000 - const: sifive,fu540 ... -- cgit v1.2.3