From: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> Some back and forth with Drew [1] about riscv_fill_hwcap() resulted in the realisation that it is not very useful to parse the DT & perform validation of riscv,isa every time we would like to get the id for a hart. Although it is no longer called in riscv_fill_hwcap(), riscv_of_processor_hartid() is called in several other places. Notably in setup_smp() it forms part of the logic for filling the mask of possible CPUs. Since a possible CPU must have passed this basic validation of riscv,isa, a repeat validation is not required. Rename riscv_of_processor_id() to riscv_early_of_processor_id(), which will be called from setup_smp() & introduce a new riscv_of_processor_id() which makes use of the pre-populated mask of possible cpus. Link: https://lore.kernel.org/linux-riscv/xvdswl3iyikwvamny7ikrxo2ncuixshtg3f6uucjahpe3xpc5c@ud4cz4fkg5dj/ [1] Reviewed-by: Andrew Jones <ajones@xxxxxxxxxxxxxxxx> Signed-off-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx> --- arch/riscv/include/asm/processor.h | 1 + arch/riscv/kernel/cpu.c | 22 +++++++++++++++++++++- arch/riscv/kernel/smpboot.c | 2 +- 3 files changed, 23 insertions(+), 2 deletions(-) diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 94a0590c6971..3479f9fca4b0 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -75,6 +75,7 @@ static inline void wait_for_interrupt(void) struct device_node; int riscv_of_processor_hartid(struct device_node *node, unsigned long *hartid); +int riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hartid); int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid); extern void riscv_fill_hwcap(void); diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index f4dadbfecd04..7030a5004f8e 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -20,6 +20,26 @@ * isn't an enabled and valid RISC-V hart node. */ int riscv_of_processor_hartid(struct device_node *node, unsigned long *hart) +{ + int cpu; + + *hart = (unsigned long)of_get_cpu_hwid(node, 0); + if (*hart == ~0UL) { + pr_warn("Found CPU without hart ID\n"); + return -ENODEV; + } + + cpu = riscv_hartid_to_cpuid(*hart); + if (cpu < 0) + return cpu; + + if (!cpu_possible(cpu)) + return -ENODEV; + + return 0; +} + +int riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hart) { const char *isa; @@ -28,7 +48,7 @@ int riscv_of_processor_hartid(struct device_node *node, unsigned long *hart) return -ENODEV; } - *hart = (unsigned long) of_get_cpu_hwid(node, 0); + *hart = (unsigned long)of_get_cpu_hwid(node, 0); if (*hart == ~0UL) { pr_warn("Found CPU without hart ID\n"); return -ENODEV; diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c index 445a4efee267..626238200010 100644 --- a/arch/riscv/kernel/smpboot.c +++ b/arch/riscv/kernel/smpboot.c @@ -81,7 +81,7 @@ void __init setup_smp(void) cpu_set_ops(0); for_each_of_cpu_node(dn) { - rc = riscv_of_processor_hartid(dn, &hart); + rc = riscv_early_of_processor_hartid(dn, &hart); if (rc < 0) continue; -- 2.39.2
