summaryrefslogtreecommitdiff
path: root/arch/riscv/kernel/cpu_ops.c
AgeCommit message (Collapse)Author
2023-04-29RISC-V: Align SBI probe implementation with specAndrew Jones
sbi_probe_extension() is specified with "Returns 0 if the given SBI extension ID (EID) is not available, or 1 if it is available unless defined as any other non-zero value by the implementation." Additionally, sbiret.value is a long. Fix the implementation to ensure any nonzero long value is considered a success, rather than only positive int values. Fixes: b9dcd9e41587 ("RISC-V: Add basic support for SBI v0.2") Signed-off-by: Andrew Jones <ajones@ventanamicro.com> Reviewed-by: Conor Dooley <conor.dooley@microchip.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230427163626.101042-1-ajones@ventanamicro.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-08-11riscv: ensure cpu_ops_sbi is declaredConor Dooley
Sparse complains that cpu_ops_sbi is used undeclared: arch/riscv/kernel/cpu_ops_sbi.c:17:29: warning: symbol 'cpu_ops_sbi' was not declared. Should it be static? Fix the warning by adding cpu_ops_sbi to cpu_ops_sbi.h & including that where used. Signed-off-by: Conor Dooley <conor.dooley@microchip.com> Link: https://lore.kernel.org/r/20220714080235.3853374-1-conor.dooley@microchip.com Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-08-11RISC-V: Declare cpu_ops_spinwait in <asm/cpu_ops.h>Ben Dooks
The cpu_ops_spinwait is used in a couple of places in arch/riscv and is causing a sparse warning due to no declaration. Add this to <asm/cpu_ops.h> with the others to fix the following: arch/riscv/kernel/cpu_ops_spinwait.c:16:29: warning: symbol 'cpu_ops_spinwait' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben.dooks@sifive.com> Link: https://lore.kernel.org/r/20220714071811.187491-1-ben.dooks@sifive.com [Palmer: Drop the extern from cpu_ops.c] Fixes: 2ffc48fc7071 ("RISC-V: Move spinwait booting method to its own config") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Move spinwait booting method to its own configAtish Patra
The spinwait booting method should only be used for platforms with older firmware without SBI HSM extension or M-mode firmware because spinwait method can't support cpu hotplug, kexec or sparse hartid. It is better to move the entire spinwait implementation to its own config which can be disabled if required. It is enabled by default to maintain backward compatibility and M-mode Linux. Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20RISC-V: Use __cpu_up_stack/task_pointer only for spinwait methodAtish Patra
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>
2022-01-20RISC-V: Do not print the SBI version during HSM extension boot printAtish Patra
The HSM extension information log also prints the SBI version v0.2. This is misleading as the underlying firmware SBI version may be different from v0.2. Remove the unncessary printing of SBI version. Signed-off-by: Atish Patra <atishp@rivosinc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2020-10-25treewide: Convert macro and uses of __section(foo) to __section("foo")Joe Perches
Use a more generic form for __section that requires quotes to avoid complications with clang and gcc differences. Remove the quote operator # from compiler_attributes.h __section macro. Convert all unquoted __section(foo) uses to quoted __section("foo"). Also convert __attribute__((section("foo"))) uses to __section("foo") even if the __attribute__ has multiple list entry forms. Conversion done using the script at: https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com> Reviewed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-04riscv: force __cpu_up_ variables to put in data sectionZong Li
Put __cpu_up_stack_pointer and __cpu_up_task_pointer in data section. Currently, these two variables are put in bss section, there is a potential risk that secondary harts get the uninitialized value before main hart finishing the bss clearing. In this case, all secondary harts would pass the waiting loop and enable the MMU before main hart set up the page table. This issue happens on random booting of multiple harts, which means it will manifest for BBL and OpenSBI v0.6 (or older version). In OpenSBI v0.7 (or higher version), we have HSM extension so all the secondary harts are brought-up by Linux kernel in an orderly fashion. This means we don't need this change for OpenSBI v0.7 (or higher version). Signed-off-by: Zong Li <zong.li@sifive.com> Reviewed-by: Greentime Hu <greentime.hu@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Add supported for ordered booting method using HSMAtish Patra
Currently, all harts have to jump Linux in RISC-V. This complicates the multi-stage boot process as every transient stage also has to ensure all harts enter to that stage and jump to Linux afterwards. It also obstructs a clean Kexec implementation. SBI HSM extension provides alternate solutions where only a single hart need to boot and enter Linux. The booting hart can bring up secondary harts one by one afterwards. Add SBI HSM based cpu_ops that implements an ordered booting method in RISC-V. This change is also backward compatible with older firmware not implementing HSM extension. If a latest kernel is used with older firmware, it will continue to use the default spinning booting method. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31RISC-V: Add cpu_ops and modify default booting methodAtish Patra
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>