Commit 1ec9dd80 authored by Paul Burton's avatar Paul Burton Committed by Ralf Baechle

MIPS: CPS: Detect CPUs in secondary clusters

As a first step towards supporting multi-cluster systems, detect cores &
VPs in secondary clusters & record their cluster information in the
cpu_data array. The "VP topology" line printed during boot is extended
to display multiple clusters. On a single cluster it shows output like
the following:

  VP topology: {4,4}

This would indicate a system with 2 cores which each contain 4 VPs. We
extend this to cover multiple clusters in a natural way:

  VP topology: {4,4},{2,2}

This would indicate a system with 2 clusters. The first cluster contains
2 cores which each contain 4 VPs. The second cluster contains 2 cores
which each contain 2 VPs.

Actually booting these cores & VPs is left to further patches once other
pieces are in place.
Signed-off-by: default avatarPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17017/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 3c9b4166
...@@ -40,44 +40,58 @@ static int __init setup_nothreads(char *s) ...@@ -40,44 +40,58 @@ static int __init setup_nothreads(char *s)
} }
early_param("nothreads", setup_nothreads); early_param("nothreads", setup_nothreads);
static unsigned core_vpe_count(unsigned core) static unsigned core_vpe_count(unsigned int cluster, unsigned core)
{ {
if (threads_disabled) if (threads_disabled)
return 1; return 1;
return mips_cps_numvps(0, core); return mips_cps_numvps(cluster, core);
} }
static void __init cps_smp_setup(void) static void __init cps_smp_setup(void)
{ {
unsigned int ncores, nvpes, core_vpes; unsigned int nclusters, ncores, nvpes, core_vpes;
unsigned long core_entry; unsigned long core_entry;
int c, v; int cl, c, v;
/* Detect & record VPE topology */ /* Detect & record VPE topology */
ncores = mips_cps_numcores(0); nvpes = 0;
nclusters = mips_cps_numclusters();
pr_info("%s topology ", cpu_has_mips_r6 ? "VP" : "VPE"); pr_info("%s topology ", cpu_has_mips_r6 ? "VP" : "VPE");
for (c = nvpes = 0; c < ncores; c++) { for (cl = 0; cl < nclusters; cl++) {
core_vpes = core_vpe_count(c); if (cl > 0)
pr_cont("%c%u", c ? ',' : '{', core_vpes); pr_cont(",");
pr_cont("{");
/* Use the number of VPEs in core 0 for smp_num_siblings */
if (!c) ncores = mips_cps_numcores(cl);
smp_num_siblings = core_vpes; for (c = 0; c < ncores; c++) {
core_vpes = core_vpe_count(cl, c);
if (c > 0)
pr_cont(",");
pr_cont("%u", core_vpes);
/* Use the number of VPEs in cluster 0 core 0 for smp_num_siblings */
if (!cl && !c)
smp_num_siblings = core_vpes;
for (v = 0; v < min_t(int, core_vpes, NR_CPUS - nvpes); v++) {
cpu_set_cluster(&cpu_data[nvpes + v], cl);
cpu_set_core(&cpu_data[nvpes + v], c);
cpu_set_vpe_id(&cpu_data[nvpes + v], v);
}
for (v = 0; v < min_t(int, core_vpes, NR_CPUS - nvpes); v++) { nvpes += core_vpes;
cpu_set_core(&cpu_data[nvpes + v], c);
cpu_set_vpe_id(&cpu_data[nvpes + v], v);
} }
nvpes += core_vpes; pr_cont("}");
} }
pr_cont("} total %u\n", nvpes); pr_cont(" total %u\n", nvpes);
/* Indicate present CPUs (CPU being synonymous with VPE) */ /* Indicate present CPUs (CPU being synonymous with VPE) */
for (v = 0; v < min_t(unsigned, nvpes, NR_CPUS); v++) { for (v = 0; v < min_t(unsigned, nvpes, NR_CPUS); v++) {
set_cpu_possible(v, true); set_cpu_possible(v, cpu_cluster(&cpu_data[v]) == 0);
set_cpu_present(v, true); set_cpu_present(v, cpu_cluster(&cpu_data[v]) == 0);
__cpu_number_map[v] = v; __cpu_number_map[v] = v;
__cpu_logical_map[v] = v; __cpu_logical_map[v] = v;
} }
...@@ -109,7 +123,7 @@ static void __init cps_smp_setup(void) ...@@ -109,7 +123,7 @@ static void __init cps_smp_setup(void)
static void __init cps_prepare_cpus(unsigned int max_cpus) static void __init cps_prepare_cpus(unsigned int max_cpus)
{ {
unsigned ncores, core_vpes, c, cca; unsigned ncores, core_vpes, c, cca;
bool cca_unsuitable; bool cca_unsuitable, cores_limited;
u32 *entry_code; u32 *entry_code;
mips_mt_set_cpuoptions(); mips_mt_set_cpuoptions();
...@@ -129,19 +143,22 @@ static void __init cps_prepare_cpus(unsigned int max_cpus) ...@@ -129,19 +143,22 @@ static void __init cps_prepare_cpus(unsigned int max_cpus)
} }
/* Warn the user if the CCA prevents multi-core */ /* Warn the user if the CCA prevents multi-core */
ncores = mips_cps_numcores(0); cores_limited = false;
if ((cca_unsuitable || cpu_has_dc_aliases) && ncores > 1) { if (cca_unsuitable || cpu_has_dc_aliases) {
for_each_present_cpu(c) {
if (cpus_are_siblings(smp_processor_id(), c))
continue;
set_cpu_present(c, false);
cores_limited = true;
}
}
if (cores_limited)
pr_warn("Using only one core due to %s%s%s\n", pr_warn("Using only one core due to %s%s%s\n",
cca_unsuitable ? "unsuitable CCA" : "", cca_unsuitable ? "unsuitable CCA" : "",
(cca_unsuitable && cpu_has_dc_aliases) ? " & " : "", (cca_unsuitable && cpu_has_dc_aliases) ? " & " : "",
cpu_has_dc_aliases ? "dcache aliasing" : ""); cpu_has_dc_aliases ? "dcache aliasing" : "");
for_each_present_cpu(c) {
if (!cpus_are_siblings(smp_processor_id(), c))
set_cpu_present(c, false);
}
}
/* /*
* Patch the start of mips_cps_core_entry to provide: * Patch the start of mips_cps_core_entry to provide:
* *
...@@ -156,6 +173,7 @@ static void __init cps_prepare_cpus(unsigned int max_cpus) ...@@ -156,6 +173,7 @@ static void __init cps_prepare_cpus(unsigned int max_cpus)
__sync(); __sync();
/* Allocate core boot configuration structs */ /* Allocate core boot configuration structs */
ncores = mips_cps_numcores(0);
mips_cps_core_bootcfg = kcalloc(ncores, sizeof(*mips_cps_core_bootcfg), mips_cps_core_bootcfg = kcalloc(ncores, sizeof(*mips_cps_core_bootcfg),
GFP_KERNEL); GFP_KERNEL);
if (!mips_cps_core_bootcfg) { if (!mips_cps_core_bootcfg) {
...@@ -165,7 +183,7 @@ static void __init cps_prepare_cpus(unsigned int max_cpus) ...@@ -165,7 +183,7 @@ static void __init cps_prepare_cpus(unsigned int max_cpus)
/* Allocate VPE boot configuration structs */ /* Allocate VPE boot configuration structs */
for (c = 0; c < ncores; c++) { for (c = 0; c < ncores; c++) {
core_vpes = core_vpe_count(c); core_vpes = core_vpe_count(0, c);
mips_cps_core_bootcfg[c].vpe_config = kcalloc(core_vpes, mips_cps_core_bootcfg[c].vpe_config = kcalloc(core_vpes,
sizeof(*mips_cps_core_bootcfg[c].vpe_config), sizeof(*mips_cps_core_bootcfg[c].vpe_config),
GFP_KERNEL); GFP_KERNEL);
...@@ -288,6 +306,10 @@ static int cps_boot_secondary(int cpu, struct task_struct *idle) ...@@ -288,6 +306,10 @@ static int cps_boot_secondary(int cpu, struct task_struct *idle)
unsigned int remote; unsigned int remote;
int err; int err;
/* We don't yet support booting CPUs in other clusters */
if (cpu_cluster(&cpu_data[cpu]) != cpu_cluster(&current_cpu_data))
return -ENOSYS;
vpe_cfg->pc = (unsigned long)&smp_bootstrap; vpe_cfg->pc = (unsigned long)&smp_bootstrap;
vpe_cfg->sp = __KSTK_TOS(idle); vpe_cfg->sp = __KSTK_TOS(idle);
vpe_cfg->gp = (unsigned long)task_thread_info(idle); vpe_cfg->gp = (unsigned long)task_thread_info(idle);
......
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