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authorConor Dooley <conor.dooley@microchip.com>2022-07-15 18:51:55 +0100
committerConor Dooley <conor.dooley@microchip.com>2022-08-15 00:42:28 +0100
commit456797da792fa7cbf6698febf275fe9b36691f78 (patch)
tree1abb1386d52c19ec07462b37f63257e19136ff8b /arch/arm64/kernel/topology.c
parentLinux 6.0-rc1 (diff)
downloadlinux-dev-456797da792fa7cbf6698febf275fe9b36691f78.tar.xz
linux-dev-456797da792fa7cbf6698febf275fe9b36691f78.zip
arm64: topology: move store_cpu_topology() to shared code
arm64's method of defining a default cpu topology requires only minimal changes to apply to RISC-V also. The current arm64 implementation exits early in a uniprocessor configuration by reading MPIDR & claiming that uniprocessor can rely on the default values. This is appears to be a hangover from prior to '3102bc0e6ac7 ("arm64: topology: Stop using MPIDR for topology information")', because the current code just assigns default values for multiprocessor systems. With the MPIDR references removed, store_cpu_topolgy() can be moved to the common arch_topology code. Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Atish Patra <atishp@rivosinc.com> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Diffstat (limited to 'arch/arm64/kernel/topology.c')
-rw-r--r--arch/arm64/kernel/topology.c40
1 files changed, 0 insertions, 40 deletions
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index 869ffc4d4484..7889a00f5487 100644
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -22,46 +22,6 @@
#include <asm/cputype.h>
#include <asm/topology.h>
-void store_cpu_topology(unsigned int cpuid)
-{
- struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
- u64 mpidr;
-
- if (cpuid_topo->package_id != -1)
- goto topology_populated;
-
- mpidr = read_cpuid_mpidr();
-
- /* Uniprocessor systems can rely on default topology values */
- if (mpidr & MPIDR_UP_BITMASK)
- return;
-
- /*
- * This would be the place to create cpu topology based on MPIDR.
- *
- * However, it cannot be trusted to depict the actual topology; some
- * pieces of the architecture enforce an artificial cap on Aff0 values
- * (e.g. GICv3's ICC_SGI1R_EL1 limits it to 15), leading to an
- * artificial cycling of Aff1, Aff2 and Aff3 values. IOW, these end up
- * having absolutely no relationship to the actual underlying system
- * topology, and cannot be reasonably used as core / package ID.
- *
- * If the MT bit is set, Aff0 *could* be used to define a thread ID, but
- * we still wouldn't be able to obtain a sane core ID. This means we
- * need to entirely ignore MPIDR for any topology deduction.
- */
- cpuid_topo->thread_id = -1;
- cpuid_topo->core_id = cpuid;
- cpuid_topo->package_id = cpu_to_node(cpuid);
-
- pr_debug("CPU%u: cluster %d core %d thread %d mpidr %#016llx\n",
- cpuid, cpuid_topo->package_id, cpuid_topo->core_id,
- cpuid_topo->thread_id, mpidr);
-
-topology_populated:
- update_siblings_masks(cpuid);
-}
-
#ifdef CONFIG_ACPI
static bool __init acpi_cpu_is_threaded(int cpu)
{