aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--target/linux/ramips/patches-4.4/100-mt7621-core-detect-hack.patch61
1 files changed, 61 insertions, 0 deletions
diff --git a/target/linux/ramips/patches-4.4/100-mt7621-core-detect-hack.patch b/target/linux/ramips/patches-4.4/100-mt7621-core-detect-hack.patch
new file mode 100644
index 0000000000..4049d131bb
--- /dev/null
+++ b/target/linux/ramips/patches-4.4/100-mt7621-core-detect-hack.patch
@@ -0,0 +1,61 @@
+There is a variant of MT7621 which contains only one CPU core instead of 2.
+This is not reflected in the config register, so the kernel detects more
+physical cores, which leads to a hang on SMP bringup.
+Add a hack to detect missing cores.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+
+--- a/arch/mips/kernel/smp-cps.c
++++ b/arch/mips/kernel/smp-cps.c
+@@ -44,6 +44,11 @@ static unsigned core_vpe_count(unsigned
+ return (cfg >> CM_GCR_Cx_CONFIG_PVPE_SHF) + 1;
+ }
+
++bool __weak plat_cpu_core_present(int core)
++{
++ return true;
++}
++
+ static void __init cps_smp_setup(void)
+ {
+ unsigned int ncores, nvpes, core_vpes;
+@@ -53,6 +58,8 @@ static void __init cps_smp_setup(void)
+ ncores = mips_cm_numcores();
+ pr_info("VPE topology ");
+ for (c = nvpes = 0; c < ncores; c++) {
++ if (!plat_cpu_core_present(c))
++ continue;
+ core_vpes = core_vpe_count(c);
+ pr_cont("%c%u", c ? ',' : '{', core_vpes);
+
+--- a/arch/mips/ralink/mt7621.c
++++ b/arch/mips/ralink/mt7621.c
+@@ -20,6 +20,7 @@
+ #include <asm/mips-cpc.h>
+ #include <asm/mach-ralink/ralink_regs.h>
+ #include <asm/mach-ralink/mt7621.h>
++#include <asm/mips-boards/launch.h>
+
+ #include <pinmux.h>
+
+@@ -163,6 +164,20 @@ void __init ralink_of_remap(void)
+ panic("Failed to remap core resources");
+ }
+
++bool plat_cpu_core_present(int core)
++{
++ struct cpulaunch *launch = (struct cpulaunch *)CKSEG0ADDR(CPULAUNCH);
++
++ if (!core)
++ return true;
++ launch += core * 2; /* 2 VPEs per core */
++ if (!(launch->flags & LAUNCH_FREADY))
++ return false;
++ if (launch->flags & (LAUNCH_FGO | LAUNCH_FGONE))
++ return false;
++ return true;
++}
++
+ void prom_soc_init(struct ralink_soc_info *soc_info)
+ {
+ void __iomem *sysc = (void __iomem *) KSEG1ADDR(MT7621_SYSC_BASE);