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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/powerpc/include/asm/cpuidle.h
parentInitial commit. (diff)
downloadlinux-upstream/4.19.249.tar.xz
linux-upstream/4.19.249.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/include/asm/cpuidle.h')
-rw-r--r--arch/powerpc/include/asm/cpuidle.h118
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/cpuidle.h b/arch/powerpc/include/asm/cpuidle.h
new file mode 100644
index 000000000..43e5f31fe
--- /dev/null
+++ b/arch/powerpc/include/asm/cpuidle.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_POWERPC_CPUIDLE_H
+#define _ASM_POWERPC_CPUIDLE_H
+
+#ifdef CONFIG_PPC_POWERNV
+/* Thread state used in powernv idle state management */
+#define PNV_THREAD_RUNNING 0
+#define PNV_THREAD_NAP 1
+#define PNV_THREAD_SLEEP 2
+#define PNV_THREAD_WINKLE 3
+
+/*
+ * Core state used in powernv idle for POWER8.
+ *
+ * The lock bit synchronizes updates to the state, as well as parts of the
+ * sleep/wake code (see kernel/idle_book3s.S).
+ *
+ * Bottom 8 bits track the idle state of each thread. Bit is cleared before
+ * the thread executes an idle instruction (nap/sleep/winkle).
+ *
+ * Then there is winkle tracking. A core does not lose complete state
+ * until every thread is in winkle. So the winkle count field counts the
+ * number of threads in winkle (small window of false positives is okay
+ * around the sleep/wake, so long as there are no false negatives).
+ *
+ * When the winkle count reaches 8 (the COUNT_ALL_BIT becomes set), then
+ * the THREAD_WINKLE_BITS are set, which indicate which threads have not
+ * yet woken from the winkle state.
+ */
+#define PNV_CORE_IDLE_LOCK_BIT 0x10000000
+
+#define PNV_CORE_IDLE_WINKLE_COUNT 0x00010000
+#define PNV_CORE_IDLE_WINKLE_COUNT_ALL_BIT 0x00080000
+#define PNV_CORE_IDLE_WINKLE_COUNT_BITS 0x000F0000
+#define PNV_CORE_IDLE_THREAD_WINKLE_BITS_SHIFT 8
+#define PNV_CORE_IDLE_THREAD_WINKLE_BITS 0x0000FF00
+
+#define PNV_CORE_IDLE_THREAD_BITS 0x000000FF
+
+/*
+ * ============================ NOTE =================================
+ * The older firmware populates only the RL field in the psscr_val and
+ * sets the psscr_mask to 0xf. On such a firmware, the kernel sets the
+ * remaining PSSCR fields to default values as follows:
+ *
+ * - ESL and EC bits are to 1. So wakeup from any stop state will be
+ * at vector 0x100.
+ *
+ * - MTL and PSLL are set to the maximum allowed value as per the ISA,
+ * i.e. 15.
+ *
+ * - The Transition Rate, TR is set to the Maximum value 3.
+ */
+#define PSSCR_HV_DEFAULT_VAL (PSSCR_ESL | PSSCR_EC | \
+ PSSCR_PSLL_MASK | PSSCR_TR_MASK | \
+ PSSCR_MTL_MASK)
+
+#define PSSCR_HV_DEFAULT_MASK (PSSCR_ESL | PSSCR_EC | \
+ PSSCR_PSLL_MASK | PSSCR_TR_MASK | \
+ PSSCR_MTL_MASK | PSSCR_RL_MASK)
+#define PSSCR_EC_SHIFT 20
+#define PSSCR_ESL_SHIFT 21
+#define GET_PSSCR_EC(x) (((x) & PSSCR_EC) >> PSSCR_EC_SHIFT)
+#define GET_PSSCR_ESL(x) (((x) & PSSCR_ESL) >> PSSCR_ESL_SHIFT)
+#define GET_PSSCR_RL(x) ((x) & PSSCR_RL_MASK)
+
+#define ERR_EC_ESL_MISMATCH -1
+#define ERR_DEEP_STATE_ESL_MISMATCH -2
+
+#ifndef __ASSEMBLY__
+/* Additional SPRs that need to be saved/restored during stop */
+struct stop_sprs {
+ u64 pid;
+ u64 ldbar;
+ u64 fscr;
+ u64 hfscr;
+ u64 mmcr1;
+ u64 mmcr2;
+ u64 mmcra;
+};
+
+#define PNV_IDLE_NAME_LEN 16
+struct pnv_idle_states_t {
+ char name[PNV_IDLE_NAME_LEN];
+ u32 latency_ns;
+ u32 residency_ns;
+ u64 psscr_val;
+ u64 psscr_mask;
+ u32 flags;
+ bool valid;
+};
+
+extern struct pnv_idle_states_t *pnv_idle_states;
+extern int nr_pnv_idle_states;
+extern u32 pnv_fastsleep_workaround_at_entry[];
+extern u32 pnv_fastsleep_workaround_at_exit[];
+
+extern u64 pnv_first_deep_stop_state;
+
+unsigned long pnv_cpu_offline(unsigned int cpu);
+int validate_psscr_val_mask(u64 *psscr_val, u64 *psscr_mask, u32 flags);
+static inline void report_invalid_psscr_val(u64 psscr_val, int err)
+{
+ switch (err) {
+ case ERR_EC_ESL_MISMATCH:
+ pr_warn("Invalid psscr 0x%016llx : ESL,EC bits unequal",
+ psscr_val);
+ break;
+ case ERR_DEEP_STATE_ESL_MISMATCH:
+ pr_warn("Invalid psscr 0x%016llx : ESL cleared for deep stop-state",
+ psscr_val);
+ }
+}
+#endif
+
+#endif
+
+#endif