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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/riscv/kernel/cpu_ops_sbi.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/riscv/kernel/cpu_ops_sbi.c115
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpu_ops_sbi.c b/arch/riscv/kernel/cpu_ops_sbi.c
new file mode 100644
index 000000000..685fae72b
--- /dev/null
+++ b/arch/riscv/kernel/cpu_ops_sbi.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * HSM extension and cpu_ops implementation.
+ *
+ * Copyright (c) 2020 Western Digital Corporation or its affiliates.
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <asm/cpu_ops.h>
+#include <asm/sbi.h>
+#include <asm/smp.h>
+
+extern char secondary_start_sbi[];
+const struct cpu_operations cpu_ops_sbi;
+
+static int sbi_hsm_hart_start(unsigned long hartid, unsigned long saddr,
+ unsigned long priv)
+{
+ struct sbiret ret;
+
+ ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_START,
+ hartid, saddr, priv, 0, 0, 0);
+ if (ret.error)
+ return sbi_err_map_linux_errno(ret.error);
+ else
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int sbi_hsm_hart_stop(void)
+{
+ struct sbiret ret;
+
+ ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_STOP, 0, 0, 0, 0, 0, 0);
+
+ if (ret.error)
+ return sbi_err_map_linux_errno(ret.error);
+ else
+ return 0;
+}
+
+static int sbi_hsm_hart_get_status(unsigned long hartid)
+{
+ struct sbiret ret;
+
+ ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_STATUS,
+ hartid, 0, 0, 0, 0, 0);
+ if (ret.error)
+ return sbi_err_map_linux_errno(ret.error);
+ else
+ return ret.value;
+}
+#endif
+
+static int sbi_cpu_start(unsigned int cpuid, struct task_struct *tidle)
+{
+ int rc;
+ unsigned long boot_addr = __pa_symbol(secondary_start_sbi);
+ int hartid = cpuid_to_hartid_map(cpuid);
+
+ cpu_update_secondary_bootdata(cpuid, tidle);
+ rc = sbi_hsm_hart_start(hartid, boot_addr, 0);
+
+ return rc;
+}
+
+static int sbi_cpu_prepare(unsigned int cpuid)
+{
+ if (!cpu_ops_sbi.cpu_start) {
+ pr_err("cpu start method not defined for CPU [%d]\n", cpuid);
+ return -ENODEV;
+ }
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int sbi_cpu_disable(unsigned int cpuid)
+{
+ if (!cpu_ops_sbi.cpu_stop)
+ return -EOPNOTSUPP;
+ return 0;
+}
+
+static void sbi_cpu_stop(void)
+{
+ int ret;
+
+ ret = sbi_hsm_hart_stop();
+ pr_crit("Unable to stop the cpu %u (%d)\n", smp_processor_id(), ret);
+}
+
+static int sbi_cpu_is_stopped(unsigned int cpuid)
+{
+ int rc;
+ int hartid = cpuid_to_hartid_map(cpuid);
+
+ rc = sbi_hsm_hart_get_status(hartid);
+
+ if (rc == SBI_HSM_HART_STATUS_STOPPED)
+ return 0;
+ return rc;
+}
+#endif
+
+const struct cpu_operations cpu_ops_sbi = {
+ .name = "sbi",
+ .cpu_prepare = sbi_cpu_prepare,
+ .cpu_start = sbi_cpu_start,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_disable = sbi_cpu_disable,
+ .cpu_stop = sbi_cpu_stop,
+ .cpu_is_stopped = sbi_cpu_is_stopped,
+#endif
+};