linux.git/arch/riscv/kernel/cpu_ops_spinwait.c, branch v6.9 Linux kernel source tree riscv: Remove unused members from struct cpu_operations 2024-01-04T23:03:06+00:00 Samuel Holland samuel.holland@sifive.com 2023-11-21T23:47:25+00:00 79093f3ec39c90edf4bd1a532d922ee6163441ec name is not used anywhere at all. cpu_prepare and cpu_disable do nothing and always return 0 if implemented. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20231121234736.3489608-3-samuel.holland@sifive.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> 
name is not used anywhere at all. cpu_prepare and cpu_disable do nothing
and always return 0 if implemented.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20231121234736.3489608-3-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V: cpu_ops_spinwait.c should include head.h 2022-08-11T20:24:16+00:00 Ben Dooks ben.dooks@sifive.com 2022-07-13T21:53:06+00:00 e4aa991c05aedc3ead92d1352af86db74090dc3c Running sparse shows cpu_ops_spinwait.c is missing two definitions found in head.h, so include it to stop the following warnings: arch/riscv/kernel/cpu_ops_spinwait.c:15:6: warning: symbol '__cpu_spinwait_stack_pointer' was not declared. Should it be static? arch/riscv/kernel/cpu_ops_spinwait.c:16:6: warning: symbol '__cpu_spinwait_task_pointer' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben.dooks@sifive.com> Link: https://lore.kernel.org/r/20220713215306.94675-1-ben.dooks@sifive.com Fixes: c78f94f35cf6 ("RISC-V: Use __cpu_up_stack/task_pointer only for spinwait method") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> 
Running sparse shows cpu_ops_spinwait.c is missing two definitions
found in head.h, so include it to stop the following warnings:

arch/riscv/kernel/cpu_ops_spinwait.c:15:6: warning: symbol '__cpu_spinwait_stack_pointer' was not declared. Should it be static?
arch/riscv/kernel/cpu_ops_spinwait.c:16:6: warning: symbol '__cpu_spinwait_task_pointer' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@sifive.com>
Link: https://lore.kernel.org/r/20220713215306.94675-1-ben.dooks@sifive.com
Fixes: c78f94f35cf6 ("RISC-V: Use __cpu_up_stack/task_pointer only for spinwait method")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
riscv: spinwait: Fix hartid variable type 2022-07-19T23:39:03+00:00 Sunil V L sunilvl@ventanamicro.com 2022-05-27T05:17:40+00:00 c029e487e7c00e5594a4ae946952605db34e359b The hartid variable is of type int but compared with ULONG_MAX(INVALID_HARTID). This issue is fixed by changing the hartid variable type to unsigned long. Fixes: c78f94f35cf6 ("RISC-V: Use __cpu_up_stack/task_pointer only for spinwait method") Signed-off-by: Sunil V L <sunilvl@ventanamicro.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Link: https://lore.kernel.org/r/20220527051743.2829940-3-sunilvl@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> 
The hartid variable is of type int but compared with
ULONG_MAX(INVALID_HARTID). This issue is fixed by changing
the hartid variable type to unsigned long.

Fixes: c78f94f35cf6 ("RISC-V: Use __cpu_up_stack/task_pointer only for spinwait method")

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20220527051743.2829940-3-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V: Use __cpu_up_stack/task_pointer only for spinwait method 2022-01-20T17:27:08+00:00 Atish Patra atishp@rivosinc.com 2022-01-20T09:09:15+00:00 c78f94f35cf6486c4057317e8de3ddc4c62e12c7 The __cpu_up_stack/task_pointer array is only used for spinwait method now. The per cpu array based lookup is also fragile for platforms with discontiguous/sparse hartids. The spinwait method is only used for M-mode Linux or older firmwares without SBI HSM extension. For general Linux systems, ordered booting method is preferred anyways to support cpu hotplug and kexec. Make sure that __cpu_up_stack/task_pointer is only used for spinwait method. Take this opportunity to rename it to __cpu_spinwait_stack/task_pointer to emphasize the purpose as well. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> 
The __cpu_up_stack/task_pointer array is only used for spinwait method
now. The per cpu array based lookup is also fragile for platforms with
discontiguous/sparse hartids. The spinwait method is only used for
M-mode Linux or older firmwares without SBI HSM extension. For general
Linux systems, ordered booting method is preferred anyways to support
cpu hotplug and kexec.

Make sure that __cpu_up_stack/task_pointer is only used for spinwait
method. Take this opportunity to rename it to
__cpu_spinwait_stack/task_pointer to emphasize the purpose as well.

Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V: Add cpu_ops and modify default booting method 2020-03-31T18:25:56+00:00 Atish Patra atish.patra@wdc.com 2020-03-18T01:11:40+00:00 2875fe0561569f82d0e63658ccf0d11ce7da8922 Currently, all non-booting harts start booting after the booting hart updates the per-hart stack pointer. This is done in a way that, it's difficult to implement any other booting method without breaking the backward compatibility. Define a cpu_ops method that allows to introduce other booting methods in future. Modify the current booting method to be compatible with cpu_ops. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com> 
Currently, all non-booting harts start booting after the booting hart
updates the per-hart stack pointer. This is done in a way that, it's
difficult to implement any other booting method without breaking the
backward compatibility.

Define a cpu_ops method that allows to introduce other booting methods
in future. Modify the current booting method to be compatible with
cpu_ops.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>