Re: [PATCH v2 08/25] x86: mp_init: Adjust bsp_init() to return more information

On Mon, Jun 15, 2020 at 1:00 AM Simon Glass sjg@chromium.org wrote:

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 sjg@chromium.org Reviewed-by: Wolfgang Wallner wolfgang.wallner@br-automation.com

---

Changes in v2:

• Drop change to include/dm/uclass.h
• Mention error return in get_bsp()

arch/x86/cpu/mp_init.c | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-)

diff --git a/arch/x86/cpu/mp_init.c b/arch/x86/cpu/mp_init.c index e0270e71db..cd4cae559d 100644 --- a/arch/x86/cpu/mp_init.c +++ b/arch/x86/cpu/mp_init.c @@ -421,9 +421,17 @@ 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

The return value of BSP CPU number seems not useful in this patch. But I see it will be used in future patches.

• */

+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 +439,20 @@ 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;
  

}

static int mp_init_cpu(struct udevice *cpu, void *unused) @@ -476,24 +491,18 @@ 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);
  

--

Reviewed-by: Bin Meng bmeng.cn@gmail.com