From patchwork Wed Jul 8 01:34:28 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Glass X-Patchwork-Id: 240947 List-Id: U-Boot discussion From: sjg at chromium.org (Simon Glass) Date: Tue, 7 Jul 2020 19:34:28 -0600 Subject: [PATCH v4 08/25] x86: mp_init: Adjust bsp_init() to return more information In-Reply-To: <20200708013446.2600256-1-sjg@chromium.org> References: <20200708013446.2600256-1-sjg@chromium.org> Message-ID: <20200708013446.2600256-9-sjg@chromium.org> This function is misnamed since it does not actually init the BSP. Also it is convenient to adjust it to return a little more information. Rename and update the function, to allow it to return the BSP CPU device and number, as well as the total number of CPUs. Signed-off-by: Simon Glass Reviewed-by: Wolfgang Wallner Reviewed-by: Bin Meng --- Changes in v4: - Update get_bsp() to return zero when SMP is not inited Changes in v2: - Drop change to include/dm/uclass.h - Mention error return in get_bsp() arch/x86/cpu/mp_init.c | 36 +++++++++++++++++++++++------------- 1 file changed, 23 insertions(+), 13 deletions(-) diff --git a/arch/x86/cpu/mp_init.c b/arch/x86/cpu/mp_init.c index 6f6de49df0..9fdde7832a 100644 --- a/arch/x86/cpu/mp_init.c +++ b/arch/x86/cpu/mp_init.c @@ -421,9 +421,18 @@ static int bsp_do_flight_plan(struct udevice *cpu, struct mp_flight_plan *plan, return ret; } -static int init_bsp(struct udevice **devp) +/** + * get_bsp() - Get information about the bootstrap processor + * + * @devp: If non-NULL, returns CPU device corresponding to the BSP + * @cpu_countp: If non-NULL, returns the total number of CPUs + * @return CPU number of the BSP, or -ve on error. If multiprocessing is not + * enabled, returns 0 + */ +static int get_bsp(struct udevice **devp, int *cpu_countp) { char processor_name[CPU_MAX_NAME_LEN]; + struct udevice *dev; int apic_id; int ret; @@ -431,13 +440,20 @@ static int init_bsp(struct udevice **devp) debug("CPU: %s\n", processor_name); apic_id = lapicid(); - ret = find_cpu_by_apic_id(apic_id, devp); - if (ret) { + ret = find_cpu_by_apic_id(apic_id, &dev); + if (ret < 0) { printf("Cannot find boot CPU, APIC ID %d\n", apic_id); return ret; } + ret = cpu_get_count(dev); + if (ret < 0) + return log_msg_ret("count", ret); + if (devp) + *devp = dev; + if (cpu_countp) + *cpu_countp = ret; - return 0; + return dev->req_seq >= 0 ? dev->req_seq : 0; } static int mp_init_cpu(struct udevice *cpu, void *unused) @@ -476,24 +492,18 @@ int mp_init(void) uclass_id_foreach_dev(UCLASS_CPU, cpu, uc) cpu->req_seq = dev_read_u32_default(cpu, "reg", -1); - ret = init_bsp(&cpu); - if (ret) { + ret = get_bsp(&cpu, &num_cpus); + if (ret < 0) { debug("Cannot init boot CPU: err=%d\n", ret); return ret; } - num_cpus = cpu_get_count(cpu); - if (num_cpus < 0) { - debug("Cannot get number of CPUs: err=%d\n", num_cpus); - return num_cpus; - } - if (num_cpus < 2) debug("Warning: Only 1 CPU is detected\n"); ret = check_cpu_devices(num_cpus); if (ret) - debug("Warning: Device tree does not describe all CPUs. Extra ones will not be started correctly\n"); + log_warning("Warning: Device tree does not describe all CPUs. Extra ones will not be started correctly\n"); /* Copy needed parameters so that APs have a reference to the plan */ mp_info.num_records = ARRAY_SIZE(mp_steps);