bmips: fix SMP CPU mapping
authorÁlvaro Fernández Rojas <noltari@gmail.com>
Tue, 23 Feb 2021 14:25:13 +0000 (15:25 +0100)
committerÁlvaro Fernández Rojas <noltari@gmail.com>
Tue, 23 Feb 2021 14:25:13 +0000 (15:25 +0100)
SMP isn't supported on BCM6358 since it has a shared TLB. Some boards boot
with CPU #1 instead of CPU #0, and this is currently not supported do to a
smp-bmips bug.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
target/linux/bmips/patches-5.10/200-mips-smp-bmips-fix-CPU-mappings.patch [new file with mode: 0644]
target/linux/bmips/patches-5.10/202-irqchip-bcm6345-l1-intc-fix-smp.patch [deleted file]

diff --git a/target/linux/bmips/patches-5.10/200-mips-smp-bmips-fix-CPU-mappings.patch b/target/linux/bmips/patches-5.10/200-mips-smp-bmips-fix-CPU-mappings.patch
new file mode 100644 (file)
index 0000000..16232f8
--- /dev/null
@@ -0,0 +1,58 @@
+From 56e3adab09cbadb30045893c10ec2ff0d629bc6f Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Tue, 23 Feb 2021 13:41:12 +0100
+Subject: [PATCH] mips: smp-bmips: fix CPU mappings
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
+CPU #0, the current CPU mapping code produces the following:
+- smp_processor_id(): 0
+- cpu_logical_map(): 1
+- cpu_number_map(): 1
+
+This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
+it is disabled and max_cpus is decreased from 2 to 1.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
+ 1 file changed, 17 insertions(+), 10 deletions(-)
+
+--- a/arch/mips/kernel/smp-bmips.c
++++ b/arch/mips/kernel/smp-bmips.c
+@@ -134,17 +134,24 @@ static void __init bmips_smp_setup(void)
+       if (!board_ebase_setup)
+               board_ebase_setup = &bmips_ebase_setup;
+-      __cpu_number_map[boot_cpu] = 0;
+-      __cpu_logical_map[0] = boot_cpu;
++      if (max_cpus > 1) {
++              __cpu_number_map[boot_cpu] = 0;
++              __cpu_logical_map[0] = boot_cpu;
+-      for (i = 0; i < max_cpus; i++) {
+-              if (i != boot_cpu) {
+-                      __cpu_number_map[i] = cpu;
+-                      __cpu_logical_map[cpu] = i;
+-                      cpu++;
++              for (i = 0; i < max_cpus; i++) {
++                      if (i != boot_cpu) {
++                              __cpu_number_map[i] = cpu;
++                              __cpu_logical_map[cpu] = i;
++                              cpu++;
++                      }
++                      set_cpu_possible(i, 1);
++                      set_cpu_present(i, 1);
+               }
+-              set_cpu_possible(i, 1);
+-              set_cpu_present(i, 1);
++      } else {
++              __cpu_number_map[0] = boot_cpu;
++              __cpu_logical_map[0] = 0;
++              set_cpu_possible(0, 1);
++              set_cpu_possible(0, 1);
+       }
+ }
diff --git a/target/linux/bmips/patches-5.10/202-irqchip-bcm6345-l1-intc-fix-smp.patch b/target/linux/bmips/patches-5.10/202-irqchip-bcm6345-l1-intc-fix-smp.patch
deleted file mode 100644 (file)
index f9001e6..0000000
+++ /dev/null
@@ -1,11 +0,0 @@
---- a/drivers/irqchip/irq-bcm6345-l1.c
-+++ b/drivers/irqchip/irq-bcm6345-l1.c
-@@ -121,7 +121,7 @@ static void bcm6345_l1_irq_handle(struct
-       unsigned int idx;
- #ifdef CONFIG_SMP
--      cpu = intc->cpus[cpu_logical_map(smp_processor_id())];
-+      cpu = intc->cpus[smp_processor_id()];
- #else
-       cpu = intc->cpus[0];
- #endif