Add ARM64-specific code to initialize the Hyper-V
hypervisor when booting as a guest VM. Provide functions
and data structures indicating hypervisor status that
are needed by VMbus driver.
This code is built only when CONFIG_HYPERV is enabled.
Signed-off-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
---
arch/arm64/hyperv/hv_init.c | 153 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 153 insertions(+)
diff --git a/arch/arm64/hyperv/hv_init.c b/arch/arm64/hyperv/hv_init.c
index 67350ec..86e4621 100644
--- a/arch/arm64/hyperv/hv_init.c
+++ b/arch/arm64/hyperv/hv_init.c
@@ -13,15 +13,48 @@
#include <linux/types.h>
#include <linux/version.h>
#include <linux/export.h>
+#include <linux/vmalloc.h>
#include <linux/mm.h>
+#include <linux/acpi.h>
+#include <linux/module.h>
#include <linux/hyperv.h>
#include <linux/spinlock.h>
#include <linux/list.h>
#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/cpuhotplug.h>
+#include <linux/psci.h>
+#include <linux/sched_clock.h>
#include <asm-generic/bug.h>
#include <asm/hyperv-tlfs.h>
#include <asm/mshyperv.h>
+#include <asm/sysreg.h>
+#include <clocksource/hyperv_timer.h>
+static bool hyperv_initialized;
+
+struct ms_hyperv_info ms_hyperv __ro_after_init;
+EXPORT_SYMBOL_GPL(ms_hyperv);
+
+u32 *hv_vp_index;
+EXPORT_SYMBOL_GPL(hv_vp_index);
+
+u32 hv_max_vp_index;
+EXPORT_SYMBOL_GPL(hv_max_vp_index);
+
+static int hv_cpu_init(unsigned int cpu)
+{
+ u64 msr_vp_index;
+
+ hv_get_vp_index(msr_vp_index);
+
+ hv_vp_index[smp_processor_id()] = msr_vp_index;
+
+ if (msr_vp_index > hv_max_vp_index)
+ hv_max_vp_index = msr_vp_index;
+
+ return 0;
+}
/*
* Functions for allocating and freeing memory with size and
@@ -88,6 +121,120 @@ void hv_free_hyperv_page(unsigned long addr)
/*
+ * This function is invoked via the ACPI clocksource probe mechanism. We
+ * don't actually use any values from the ACPI GTDT table, but we set up
+ * the Hyper-V synthetic clocksource and do other initialization for
+ * interacting with Hyper-V the first time. Using early_initcall to invoke
+ * this function is too late because interrupts are already enabled at that
+ * point, and hv_init_clocksource() must run before interrupts are enabled.
+ *
+ * 1. Setup the guest ID.
+ * 2. Get features and hints info from Hyper-V
+ * 3. Setup per-cpu VP indices.
+ * 4. Initialize the Hyper-V clocksource.
+ */
+
+static int __init hyperv_init(struct acpi_table_header *table)
+{
+ struct hv_get_vp_register_output result;
+ u32 a, b, c, d;
+ u64 guest_id;
+ int i;
+
+ /*
+ * If we're in a VM on Hyper-V, the ACPI hypervisor_id field will
+ * have the string "MsHyperV".
+ */
+ if (strncmp((char *)&acpi_gbl_FADT.hypervisor_id, "MsHyperV", 8))
+ return -EINVAL;
+
+ /* Setup the guest ID */
+ guest_id = generate_guest_id(0, LINUX_VERSION_CODE, 0);
+ hv_set_vpreg(HV_REGISTER_GUEST_OSID, guest_id);
+
+ /* Get the features and hints from Hyper-V */
+ hv_get_vpreg_128(HV_REGISTER_PRIVILEGES_AND_FEATURES, &result);
+ ms_hyperv.features = lower_32_bits(result.registervaluelow);
+ ms_hyperv.misc_features = upper_32_bits(result.registervaluehigh);
+
+ hv_get_vpreg_128(HV_REGISTER_FEATURES, &result);
+ ms_hyperv.hints = lower_32_bits(result.registervaluelow);
+
+ pr_info("Hyper-V: Features 0x%x, hints 0x%x\n",
+ ms_hyperv.features, ms_hyperv.hints);
+
+ /*
+ * Direct mode is the only option for STIMERs provided Hyper-V
+ * on ARM64, so Hyper-V doesn't actually set the flag. But add
+ * the flag so the architecture independent code in
+ * drivers/clocksource/hyperv_timer.c will correctly use that mode.
+ */
+ ms_hyperv.misc_features |= HV_STIMER_DIRECT_MODE_AVAILABLE;
+
+ /*
+ * Hyper-V on ARM64 doesn't support AutoEOI. Add the hint
+ * that tells architecture independent code not to use this
+ * feature.
+ */
+ ms_hyperv.hints |= HV_DEPRECATING_AEOI_RECOMMENDED;
+
+ /* Get information about the Hyper-V host version */
+ hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION, &result);
+ a = lower_32_bits(result.registervaluelow);
+ b = upper_32_bits(result.registervaluelow);
+ c = lower_32_bits(result.registervaluehigh);
+ d = upper_32_bits(result.registervaluehigh);
+ pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n",
+ b >> 16, b & 0xFFFF, a, d & 0xFFFFFF, c, d >> 24);
+
+ /* Allocate and initialize percpu VP index array */
+ hv_vp_index = kmalloc_array(num_possible_cpus(), sizeof(*hv_vp_index),
+ GFP_KERNEL);
+ if (!hv_vp_index)
+ return -ENOMEM;
+
+ for (i = 0; i < num_possible_cpus(); i++)
+ hv_vp_index[i] = VP_INVAL;
+
+ if (cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "arm64/hyperv_init:online",
+ hv_cpu_init, NULL) < 0)
+ goto free_vp_index;
+
+ hv_init_clocksource();
+
+ hyperv_initialized = true;
+ return 0;
+
+free_vp_index:
+ kfree(hv_vp_index);
+ hv_vp_index = NULL;
+ return -EINVAL;
+}
+TIMER_ACPI_DECLARE(hyperv, ACPI_SIG_GTDT, hyperv_init);
+
+
+/*
+ * Called from hv_init_clocksource() to do ARM64
+ * specific initialization of the sched clock
+ */
+void __init hv_setup_sched_clock(void *sched_clock)
+{
+ sched_clock_register(sched_clock, 64, HV_CLOCK_HZ);
+}
+
+/*
+ * This routine is called before kexec/kdump, it does the required cleanup.
+ */
+void hyperv_cleanup(void)
+{
+ /* Reset our OS id */
+ hv_set_vpreg(HV_REGISTER_GUEST_OSID, 0);
+
+}
+EXPORT_SYMBOL_GPL(hyperv_cleanup);
+
+
+/*
* hv_do_hypercall- Invoke the specified hypercall
*/
u64 hv_do_hypercall(u64 control, void *input, void *output)
@@ -260,3 +407,9 @@ void hyperv_report_panic_msg(phys_addr_t pa, size_t size)
(HV_CRASH_CTL_CRASH_NOTIFY | HV_CRASH_CTL_CRASH_NOTIFY_MSG));
}
EXPORT_SYMBOL_GPL(hyperv_report_panic_msg);
+
+bool hv_is_hyperv_initialized(void)
+{
+ return hyperv_initialized;
+}
+EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized);
--
1.8.3.1
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