[PATCH v3 07/25] x86: mp_init: Set up the CPU numbers at the start

Simon Glass sjg at chromium.org
Mon Jul 6 05:37:23 CEST 2020


At present each CPU is given a number when it starts itself up. While this
saves a tiny amount of time by doing the device-tree read in parallel, it
is confusing that the numbering happens on the fly.

Move this code into mp_init() and do it at the start.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Wolfgang Wallner <wolfgang.wallner at br-automation.com>
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
---

(no changes since v1)

 arch/x86/cpu/mp_init.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/arch/x86/cpu/mp_init.c b/arch/x86/cpu/mp_init.c
index df43f71572..6f6de49df0 100644
--- a/arch/x86/cpu/mp_init.c
+++ b/arch/x86/cpu/mp_init.c
@@ -444,12 +444,6 @@ static int mp_init_cpu(struct udevice *cpu, void *unused)
 {
 	struct cpu_platdata *plat = dev_get_parent_platdata(cpu);
 
-	/*
-	 * Multiple APs are brought up simultaneously and they may get the same
-	 * seq num in the uclass_resolve_seq() during device_probe(). To avoid
-	 * this, set req_seq to the reg number in the device tree in advance.
-	 */
-	cpu->req_seq = dev_read_u32_default(cpu, "reg", -1);
 	plat->ucode_version = microcode_read_rev();
 	plat->device_id = gd->arch.x86_device;
 
@@ -465,13 +459,8 @@ int mp_init(void)
 	int num_aps, num_cpus;
 	atomic_t *ap_count;
 	struct udevice *cpu;
-	int ret;
-
-	/* This will cause the CPUs devices to be bound */
 	struct uclass *uc;
-	ret = uclass_get(UCLASS_CPU, &uc);
-	if (ret)
-		return ret;
+	int ret;
 
 	if (IS_ENABLED(CONFIG_QFW)) {
 		ret = qemu_cpu_fixup();
@@ -479,6 +468,14 @@ int mp_init(void)
 			return ret;
 	}
 
+	/*
+	 * Multiple APs are brought up simultaneously and they may get the same
+	 * seq num in the uclass_resolve_seq() during device_probe(). To avoid
+	 * this, set req_seq to the reg number in the device tree in advance.
+	 */
+	uclass_id_foreach_dev(UCLASS_CPU, cpu, uc)
+		cpu->req_seq = dev_read_u32_default(cpu, "reg", -1);
+
 	ret = init_bsp(&cpu);
 	if (ret) {
 		debug("Cannot init boot CPU: err=%d\n", ret);
-- 
2.27.0.212.ge8ba1cc988-goog



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