From cde9070d9970eef1f7ec2360586c802a16230ad8 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Fri, 10 May 2024 07:43:50 +0000
Subject: [PATCH] rtl88x2CE_WiFi_linux driver
---
kernel/arch/powerpc/platforms/pseries/smp.c | 103 +++++++++++++++++++++++++--------------------------
1 files changed, 50 insertions(+), 53 deletions(-)
diff --git a/kernel/arch/powerpc/platforms/pseries/smp.c b/kernel/arch/powerpc/platforms/pseries/smp.c
index 3df4612..f474293 100644
--- a/kernel/arch/powerpc/platforms/pseries/smp.c
+++ b/kernel/arch/powerpc/platforms/pseries/smp.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* SMP support for pSeries machines.
*
@@ -5,11 +6,6 @@
* Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
*
* Plus various changes from other IBM teams...
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
*/
@@ -24,12 +20,12 @@
#include <linux/err.h>
#include <linux/device.h>
#include <linux/cpu.h>
+#include <linux/pgtable.h>
#include <asm/ptrace.h>
#include <linux/atomic.h>
#include <asm/irq.h>
#include <asm/page.h>
-#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/smp.h>
@@ -45,10 +41,10 @@
#include <asm/dbell.h>
#include <asm/plpar_wrappers.h>
#include <asm/code-patching.h>
+#include <asm/svm.h>
+#include <asm/kvm_guest.h>
#include "pseries.h"
-#include "offline_states.h"
-
/*
* The Primary thread of each non-boot processor was started from the OF client
@@ -109,12 +105,6 @@
return 1;
}
- /* Fixup atomic count: it exited inside IRQ handler. */
- task_thread_info(paca_ptrs[lcpu]->__current)->preempt_count = 0;
-#ifdef CONFIG_HOTPLUG_CPU
- if (get_cpu_current_state(lcpu) == CPU_STATE_INACTIVE)
- goto out;
-#endif
/*
* If the RTAS start-cpu token does not exist then presume the
* cpu is already spinning.
@@ -129,9 +119,6 @@
return 0;
}
-#ifdef CONFIG_HOTPLUG_CPU
-out:
-#endif
return 1;
}
@@ -146,10 +133,6 @@
vpa_init(cpu);
cpumask_clear_cpu(cpu, of_spin_mask);
-#ifdef CONFIG_HOTPLUG_CPU
- set_cpu_current_state(cpu, CPU_STATE_ONLINE);
- set_default_offline_state(cpu);
-#endif
}
static int smp_pSeries_kick_cpu(int nr)
@@ -166,20 +149,6 @@
* the processor will continue on to secondary_start
*/
paca_ptrs[nr]->cpu_start = 1;
-#ifdef CONFIG_HOTPLUG_CPU
- set_preferred_offline_state(nr, CPU_STATE_ONLINE);
-
- if (get_cpu_current_state(nr) == CPU_STATE_INACTIVE) {
- long rc;
- unsigned long hcpuid;
-
- hcpuid = get_hard_smp_processor_id(nr);
- rc = plpar_hcall_norets(H_PROD, hcpuid);
- if (rc != H_SUCCESS)
- printk(KERN_ERR "Error: Prod to wake up processor %d "
- "Ret= %ld\n", nr, rc);
- }
-#endif
return 0;
}
@@ -191,13 +160,16 @@
return 0;
}
-static void smp_pseries_cause_ipi(int cpu)
+/* Cause IPI as setup by the interrupt controller (xics or xive) */
+static void (*ic_cause_ipi)(int cpu) __ro_after_init;
+
+/* Use msgsndp doorbells target is a sibling, else use interrupt controller */
+static void dbell_or_ic_cause_ipi(int cpu)
{
- /* POWER9 should not use this handler */
if (doorbell_try_core_ipi(cpu))
return;
- icp_ops->cause_ipi(cpu);
+ ic_cause_ipi(cpu);
}
static int pseries_cause_nmi_ipi(int cpu)
@@ -221,26 +193,51 @@
return 0;
}
-static __init void pSeries_smp_probe_xics(void)
-{
- xics_smp_probe();
-
- if (cpu_has_feature(CPU_FTR_DBELL))
- smp_ops->cause_ipi = smp_pseries_cause_ipi;
- else
- smp_ops->cause_ipi = icp_ops->cause_ipi;
-}
-
static __init void pSeries_smp_probe(void)
{
if (xive_enabled())
- /*
- * Don't use P9 doorbells when XIVE is enabled. IPIs
- * using MMIOs should be faster
- */
xive_smp_probe();
else
- pSeries_smp_probe_xics();
+ xics_smp_probe();
+
+ /* No doorbell facility, must use the interrupt controller for IPIs */
+ if (!cpu_has_feature(CPU_FTR_DBELL))
+ return;
+
+ /* Doorbells can only be used for IPIs between SMT siblings */
+ if (!cpu_has_feature(CPU_FTR_SMT))
+ return;
+
+ check_kvm_guest();
+
+ if (is_kvm_guest()) {
+ /*
+ * KVM emulates doorbells by disabling FSCR[MSGP] so msgsndp
+ * faults to the hypervisor which then reads the instruction
+ * from guest memory, which tends to be slower than using XIVE.
+ */
+ if (xive_enabled())
+ return;
+
+ /*
+ * XICS hcalls aren't as fast, so we can use msgsndp (which
+ * also helps exercise KVM emulation), however KVM can't
+ * emulate secure guests because it can't read the instruction
+ * out of their memory.
+ */
+ if (is_secure_guest())
+ return;
+ }
+
+ /*
+ * Under PowerVM, FSCR[MSGP] is enabled as guest vCPU siblings are
+ * gang scheduled on the same physical core, so doorbells are always
+ * faster than the interrupt controller, and they can be used by
+ * secure guests.
+ */
+
+ ic_cause_ipi = smp_ops->cause_ipi;
+ smp_ops->cause_ipi = dbell_or_ic_cause_ipi;
}
static struct smp_ops_t pseries_smp_ops = {
--
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