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-rw-r--r--arch/powerpc/kernel/prom.c32
1 files changed, 27 insertions, 5 deletions
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 0b5878c3125b1..1dc32a0581561 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -151,6 +151,9 @@ static void __init move_device_tree(void)
* pa-features property is missing, or a 1/0 to indicate if the feature
* is supported/not supported. Note that the bit numbers are
* big-endian to match the definition in PAPR.
+ * Note: the 'clear' flag clears the feature if the bit is set in the
+ * ibm,pa/pi-features property, it does not set the feature if the
+ * bit is clear.
*/
struct ibm_feature {
unsigned long cpu_features; /* CPU_FTR_xxx bit */
@@ -159,7 +162,7 @@ struct ibm_feature {
unsigned int cpu_user_ftrs2; /* PPC_FEATURE2_xxx bit */
unsigned char pabyte; /* byte number in ibm,pa/pi-features */
unsigned char pabit; /* bit number (big-endian) */
- unsigned char invert; /* if 1, pa bit set => clear feature */
+ unsigned char clear; /* if 1, pa bit set => clear feature */
};
static struct ibm_feature ibm_pa_features[] __initdata = {
@@ -193,6 +196,7 @@ static struct ibm_feature ibm_pa_features[] __initdata = {
*/
static struct ibm_feature ibm_pi_features[] __initdata = {
{ .pabyte = 0, .pabit = 3, .mmu_features = MMU_FTR_NX_DSI },
+ { .pabyte = 0, .pabit = 4, .cpu_features = CPU_FTR_DBELL, .clear = 1 },
};
static void __init scan_features(unsigned long node, const unsigned char *ftrs,
@@ -220,12 +224,12 @@ static void __init scan_features(unsigned long node, const unsigned char *ftrs,
if (fp->pabyte >= ftrs[0])
continue;
bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
- if (bit ^ fp->invert) {
+ if (bit && !fp->clear) {
cur_cpu_spec->cpu_features |= fp->cpu_features;
cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
cur_cpu_spec->cpu_user_features2 |= fp->cpu_user_ftrs2;
cur_cpu_spec->mmu_features |= fp->mmu_features;
- } else {
+ } else if (bit == fp->clear) {
cur_cpu_spec->cpu_features &= ~fp->cpu_features;
cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
cur_cpu_spec->cpu_user_features2 &= ~fp->cpu_user_ftrs2;
@@ -368,13 +372,31 @@ static int __init early_init_dt_scan_cpus(unsigned long node,
if (found < 0)
return 0;
- DBG("boot cpu: logical %d physical %d\n", found,
- be32_to_cpu(intserv[found_thread]));
boot_cpuid = found;
if (IS_ENABLED(CONFIG_PPC64))
boot_cpu_hwid = be32_to_cpu(intserv[found_thread]);
+ if (nr_cpu_ids % nthreads != 0) {
+ set_nr_cpu_ids(ALIGN(nr_cpu_ids, nthreads));
+ pr_warn("nr_cpu_ids was not a multiple of threads_per_core, adjusted to %d\n",
+ nr_cpu_ids);
+ }
+
+ if (boot_cpuid >= nr_cpu_ids) {
+ // Remember boot core for smp_setup_cpu_maps()
+ boot_core_hwid = be32_to_cpu(intserv[0]);
+
+ pr_warn("Boot CPU %d (core hwid %d) >= nr_cpu_ids, adjusted boot CPU to %d\n",
+ boot_cpuid, boot_core_hwid, found_thread);
+
+ // Adjust boot CPU to appear on logical core 0
+ boot_cpuid = found_thread;
+ }
+
+ DBG("boot cpu: logical %d physical %d\n", boot_cpuid,
+ be32_to_cpu(intserv[found_thread]));
+
/*
* PAPR defines "logical" PVR values for cpus that
* meet various levels of the architecture: