* [PATCH v5 1/4] clk: ingenic: Poll JZ4780 CPU1 power status atomically
2026-11-13 18:42 [PATCH v5 0/4] MIPS: CI20: Enable SMP with two CPUs Florian Fainelli
@ 2026-11-13 18:42 ` Florian Fainelli
2026-11-13 18:42 ` [PATCH v5 2/4] MIPS: Skip generic IPI setup for platform-specific callbacks Florian Fainelli
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Florian Fainelli @ 2026-11-13 18:42 UTC (permalink / raw)
To: linux-mips
Cc: Florian Fainelli, stable, Paul Cercueil, Thomas Bogendoerfer,
Paul Burton, Stephen Boyd, Brian Masney, Jerome Brunet,
周琰杰 (Zhou Yanjie), Jiaxun Yang, open list,
open list:COMMON CLK FRAMEWORK, hns, paul
The CPU1 clock enable callback runs under the clock framework's spinlock
with interrupts disabled. Its readl_poll_timeout() can sleep between
reads, which is invalid in this context when SMP powers up CPU1.
Use readl_poll_timeout_atomic() with the existing interval and timeout.
This is a prerequisite for the JZ4780 SMP bring-up path. The original
CPU1 clock implementation by Zhou Yanjie is already upstream.
Cross-built for CI20; the subsequent SMP-enabled image brought up both
CPU cores. Development and validation used Codex assistance.
CC: stable@vger.kernel.org
Fixes: 6673db4f3f26 ("clk: JZ4780: Add function for enable the second core.")
Link: https://lkml.kernel.org/r/1582215889-113034-3-git-send-email-zhouyanjie@wanyeetech.com
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes since previous posting:
- No changes to this patch.
drivers/clk/ingenic/jz4780-cgu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/ingenic/jz4780-cgu.c b/drivers/clk/ingenic/jz4780-cgu.c
index 1e88aef7ac0f..1809f8859c7e 100644
--- a/drivers/clk/ingenic/jz4780-cgu.c
+++ b/drivers/clk/ingenic/jz4780-cgu.c
@@ -242,8 +242,8 @@ static int jz4780_core1_enable(struct clk_hw *hw)
spin_unlock_irqrestore(&cgu->lock, flags);
/* wait for the CPU to be powered up */
- retval = readl_poll_timeout(cgu->base + CGU_REG_LCR, lcr,
- !(lcr & LCR_SCPUS), 10, timeout);
+ retval = readl_poll_timeout_atomic(cgu->base + CGU_REG_LCR, lcr,
+ !(lcr & LCR_SCPUS), 10, timeout);
if (retval == -ETIMEDOUT) {
pr_err("%s: Wait for power up core1 timeout\n", __func__);
return retval;
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v5 3/4] MIPS: Ingenic: Add XBurst SMP support
2026-11-13 18:42 [PATCH v5 0/4] MIPS: CI20: Enable SMP with two CPUs Florian Fainelli
2026-11-13 18:42 ` [PATCH v5 1/4] clk: ingenic: Poll JZ4780 CPU1 power status atomically Florian Fainelli
2026-11-13 18:42 ` [PATCH v5 2/4] MIPS: Skip generic IPI setup for platform-specific callbacks Florian Fainelli
@ 2026-11-13 18:42 ` Florian Fainelli
2026-11-13 18:42 ` [PATCH v5 4/4] MIPS: CI20: Enable SMP with two CPUs Florian Fainelli
3 siblings, 0 replies; 6+ messages in thread
From: Florian Fainelli @ 2026-11-13 18:42 UTC (permalink / raw)
To: linux-mips
Cc: 周琰杰 (Zhou Yanjie), Florian Fainelli,
Thomas Bogendoerfer, Paul Burton, Paul Cercueil, Stephen Boyd,
Brian Masney, Jerome Brunet, Jiaxun Yang, open list,
open list:COMMON CLK FRAMEWORK, hns, paul
From: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Add support for the second XBurst core on the JZ4780, based on Zhou
Yanjie's 2020 series and Paul Burton's original CI20 SMP implementation.
Use the CP0 mailboxes for inter-processor interrupts. Initialize CPU
presence and core IDs explicitly for generic kernels, and reject CPU
offlining until CPU teardown and restart are implemented.
XBurst stops its private cache clock when executing WAIT. Write back
the data cache before entering idle so that the other core can access
data belonging to the sleeping core. Select this wait handler only when
multiple CPUs are possible, and check pending work after the cache flush.
Enable the secondary clock outside the raw SMP lock. Use the CKSEG
aliases and pointer-sized assembly helpers for generic 64-bit builds.
Development and build/CI20 boot validation used Codex assistance; Sashiko
AI review identified the locking, topology and generic-kernel issues.
Link: https://lkml.iu.edu/hypermail/linux/kernel/2005.2/03488.html
Link: https://lists.openwall.net/linux-kernel/2020/05/13/1482
Link: https://lists.openwall.net/linux-kernel/2020/05/19/1099
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
[florian: forward ported to latest version]
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
Changes since previous posting:
- Move the generic IPI initialization guard into a separate prerequisite.
- Remove Paul Cercueil's Reviewed-by and Tested-by tags after the changes.
- Remove the CONFIG_HOTPLUG_CPU guard around xburst_cpu_disable() and mark
it __maybe_unused. Retain the initializer guard because plat_smp_ops has
no cpu_disable member when hotplug is disabled; PTR_IF() cannot fix that.
- Document the intentional work recheck after the data-cache flush: the
first need_resched() avoids an unnecessary flush, and the second checks
for work arriving during it.
Earlier changes since v3:
- Enable CPU1's clock outside the raw SMP lock.
- Initialize CPU presence and core IDs; reject unsupported CPU offlining.
- Use CKSEG aliases and pointer/long assembly helpers for 64-bit builds.
- Restrict the XBurst idle handler to systems with multiple possible CPUs
and check pending work after the cache flush.
Validation:
- Affected objects build for CI20 without CPU hotplug and generic Ingenic
32-bit and 64-bit configurations with CPU hotplug.
- The previous tree booted on CI20 with both CPUs online and successful
workers pinned to each CPU. All 11 functional boot-smoke checks passed;
the kernel-log check failed on DRM bridge/refcount warnings.
- This revision changes no runtime behavior and has not been rebooted.
Development and validation used Codex assistance. Sashiko AI review
identified the issues addressed by the changes since v3.
MAINTAINERS | 3 +-
arch/mips/Kbuild | 1 +
arch/mips/generic/init.c | 3 +
arch/mips/include/asm/ingenic-smp.h | 20 ++
arch/mips/ingenic/Kconfig | 2 +
arch/mips/ingenic/Makefile | 5 +
arch/mips/ingenic/ingenic-smp-entry.S | 54 ++++++
arch/mips/ingenic/ingenic-smp.c | 260 ++++++++++++++++++++++++++
arch/mips/kernel/idle.c | 31 ++-
9 files changed, 377 insertions(+), 2 deletions(-)
create mode 100644 arch/mips/include/asm/ingenic-smp.h
create mode 100644 arch/mips/ingenic/Makefile
create mode 100644 arch/mips/ingenic/ingenic-smp-entry.S
create mode 100644 arch/mips/ingenic/ingenic-smp.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 222b7fc2c3aa..7128df320bab 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13150,8 +13150,9 @@ L: linux-mips@vger.kernel.org
S: Maintained
F: arch/mips/boot/dts/ingenic/
F: arch/mips/generic/board-ingenic.c
+F: arch/mips/include/asm/ingenic-smp.h
F: arch/mips/include/asm/mach-ingenic/
-F: arch/mips/ingenic/Kconfig
+F: arch/mips/ingenic/
F: drivers/clk/ingenic/
F: drivers/dma/dma-jz4780.c
F: drivers/gpu/drm/ingenic/
diff --git a/arch/mips/Kbuild b/arch/mips/Kbuild
index e901bf554483..4912ab80d143 100644
--- a/arch/mips/Kbuild
+++ b/arch/mips/Kbuild
@@ -12,6 +12,7 @@ obj- := $(platform-y)
# The object files are linked as core-y files would be linked
obj-y += generic/
+obj-$(CONFIG_MACH_INGENIC) += ingenic/
obj-y += kernel/
obj-y += mm/
obj-y += net/
diff --git a/arch/mips/generic/init.c b/arch/mips/generic/init.c
index 1d712eac1617..38f294887c17 100644
--- a/arch/mips/generic/init.c
+++ b/arch/mips/generic/init.c
@@ -13,6 +13,7 @@
#include <asm/bootinfo.h>
#include <asm/fw/fw.h>
+#include <asm/ingenic-smp.h>
#include <asm/irq_cpu.h>
#include <asm/machine.h>
#include <asm/mips-cps.h>
@@ -113,6 +114,8 @@ void __init device_tree_init(void)
unflatten_and_copy_device_tree();
mips_cpc_probe();
+ if (!register_ingenic_smp_ops())
+ return;
if (!register_cps_smp_ops())
return;
if (!register_vsmp_smp_ops())
diff --git a/arch/mips/include/asm/ingenic-smp.h b/arch/mips/include/asm/ingenic-smp.h
new file mode 100644
index 000000000000..ea81c333820d
--- /dev/null
+++ b/arch/mips/include/asm/ingenic-smp.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Copyright (C) 2013 Paul Burton <paulburton@kernel.org> */
+#ifndef __ASM_INGENIC_SMP_H__
+#define __ASM_INGENIC_SMP_H__
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kconfig.h>
+
+#if defined(CONFIG_MACH_JZ4780) && defined(CONFIG_SMP)
+int __init register_ingenic_smp_ops(void);
+void xburst_secondary_cpu_entry(void);
+#else
+static inline int register_ingenic_smp_ops(void)
+{
+ return -ENODEV;
+}
+#endif
+
+#endif /* __ASM_INGENIC_SMP_H__ */
diff --git a/arch/mips/ingenic/Kconfig b/arch/mips/ingenic/Kconfig
index f595b339a4b8..583f8d3651df 100644
--- a/arch/mips/ingenic/Kconfig
+++ b/arch/mips/ingenic/Kconfig
@@ -64,6 +64,8 @@ config MACH_JZ4780
select MIPS_CPU_SCACHE
select SYS_HAS_CPU_MIPS32_R2
select SYS_SUPPORTS_HIGHMEM
+ select SYS_SUPPORTS_SMP
+ select SMP_UP if SMP
config MACH_X1000
bool
diff --git a/arch/mips/ingenic/Makefile b/arch/mips/ingenic/Makefile
new file mode 100644
index 000000000000..fc3b1bf1f25a
--- /dev/null
+++ b/arch/mips/ingenic/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0
+
+ifdef CONFIG_SMP
+obj-$(CONFIG_MACH_JZ4780) += ingenic-smp.o ingenic-smp-entry.o
+endif
diff --git a/arch/mips/ingenic/ingenic-smp-entry.S b/arch/mips/ingenic/ingenic-smp-entry.S
new file mode 100644
index 000000000000..290e23c65707
--- /dev/null
+++ b/arch/mips/ingenic/ingenic-smp-entry.S
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2013 Paul Burton <paulburton@kernel.org>
+ * XBurst secondary CPU reset entry
+ */
+
+#include <asm/addrspace.h>
+#include <asm/asm.h>
+#include <asm/asmmacro.h>
+#include <asm/cacheops.h>
+#include <asm/mipsregs.h>
+
+#define CACHE_SIZE (32 * 1024)
+#define CACHE_LINESIZE 32
+
+ /* The CP0 REIM register only stores the upper 16 address bits. */
+ .section .text.smp-entry, "ax"
+ .balign 0x10000
+ .set noreorder
+LEAF(xburst_secondary_cpu_entry)
+ mtc0 zero, CP0_CAUSE
+ li t0, ST0_CU0
+ mtc0 t0, CP0_STATUS
+ ehb
+
+ /* Invalidate both private caches before entering cached code. */
+ PTR_LI t0, CKSEG0
+ ori t1, t0, CACHE_SIZE
+ mtc0 zero, CP0_TAGLO
+ ehb
+1: cache Index_Store_Tag_I, 0(t0)
+ cache Index_Store_Tag_D, 0(t0)
+ addiu t0, t0, CACHE_LINESIZE
+ bne t0, t1, 1b
+ nop
+
+ mfc0 t0, CP0_CONFIG
+ li t1, ~CONF_CM_CMASK
+ and t0, t0, t1
+ ori t0, t0, CONF_CM_CACHABLE_NONCOHERENT
+ mtc0 t0, CP0_CONFIG
+ mtc0 zero, CP0_PAGEMASK
+ ehb
+
+ /* CPU0 publishes these in RAM before releasing CPU1 from reset. */
+ PTR_LA t0, xburst_cpu_entry_sp
+ LONG_L sp, 0(t0)
+ PTR_LA t0, xburst_cpu_entry_gp
+ LONG_L gp, 0(t0)
+
+ PTR_LA t0, smp_bootstrap
+ jr t0
+ nop
+END(xburst_secondary_cpu_entry)
diff --git a/arch/mips/ingenic/ingenic-smp.c b/arch/mips/ingenic/ingenic-smp.c
new file mode 100644
index 000000000000..27b9b573a7e0
--- /dev/null
+++ b/arch/mips/ingenic/ingenic-smp.c
@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * XBurst SMP support, based on Paul Burton's CI20 implementation and
+ * Zhou Yanjie's 2020 JZ4780 SMP series.
+ * Copyright (C) 2013 Paul Burton <paulburton@kernel.org>
+ */
+
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_clk.h>
+#include <linux/sched/task_stack.h>
+#include <linux/smp.h>
+
+#include <asm/addrspace.h>
+#include <asm/irq_cpu.h>
+#include <asm/mipsregs.h>
+#include <asm/r4kcache.h>
+#include <asm/smp-ops.h>
+
+#include <asm/ingenic-smp.h>
+
+#define read_c0_corectrl() __read_32bit_c0_register($12, 2)
+#define write_c0_corectrl(val) __write_32bit_c0_register($12, 2, val)
+#define read_c0_corestatus() __read_32bit_c0_register($12, 3)
+#define write_c0_corestatus(val) __write_32bit_c0_register($12, 3, val)
+#define read_c0_reim() __read_32bit_c0_register($12, 4)
+#define write_c0_reim(val) __write_32bit_c0_register($12, 4, val)
+#define read_c0_mailbox0() __read_32bit_c0_register($20, 0)
+#define write_c0_mailbox0(val) __write_32bit_c0_register($20, 0, val)
+#define read_c0_mailbox1() __read_32bit_c0_register($20, 1)
+#define write_c0_mailbox1(val) __write_32bit_c0_register($20, 1, val)
+
+#define XBURST_MBOX_IRQ (MIPS_CPU_IRQ_BASE + 3)
+#define CORECTRL_SWRST(cpu) BIT(cpu)
+#define CORECTRL_RPC(cpu) BIT(8 + (cpu))
+#define CORESTATUS_MIRQ(cpu) BIT(cpu)
+#define REIM_ENTRY GENMASK(31, 16)
+#define REIM_MBOXIRQ(cpu) BIT(cpu)
+
+static struct clk *cpu1_clock;
+static DEFINE_RAW_SPINLOCK(smp_lock);
+
+/* Referenced by the uncached secondary CPU reset entry. */
+unsigned long xburst_cpu_entry_sp;
+unsigned long xburst_cpu_entry_gp;
+
+static irqreturn_t xburst_mbox_interrupt(int irq, void *dev_id)
+{
+ unsigned int cpu = cpu_logical_map(smp_processor_id());
+ u32 action, status;
+
+ raw_spin_lock(&smp_lock);
+ if (cpu == 0) {
+ action = read_c0_mailbox0();
+ write_c0_mailbox0(0);
+ } else {
+ action = read_c0_mailbox1();
+ write_c0_mailbox1(0);
+ }
+
+ status = read_c0_corestatus();
+ write_c0_corestatus(status & ~CORESTATUS_MIRQ(cpu));
+ irq_disable_hazard();
+ raw_spin_unlock(&smp_lock);
+
+ if (action & SMP_RESCHEDULE_YOURSELF)
+ scheduler_ipi();
+ if (action & SMP_CALL_FUNCTION)
+ generic_smp_call_function_interrupt();
+
+ return IRQ_HANDLED;
+}
+
+static void __init xburst_smp_setup(void)
+{
+ struct device_node *np;
+ u32 entry, reim;
+ unsigned int cpu = 0;
+ u64 hwid;
+
+ for_each_of_cpu_node(np) {
+ hwid = of_get_cpu_hwid(np, 0);
+ if (!of_device_is_available(np) ||
+ hwid >= ARRAY_SIZE(__cpu_number_map))
+ continue;
+ if (cpu >= nr_cpu_ids) {
+ of_node_put(np);
+ break;
+ }
+ __cpu_number_map[hwid] = cpu;
+ __cpu_logical_map[cpu] = hwid;
+ set_cpu_possible(cpu, true);
+ set_cpu_present(cpu, true);
+ cpu_set_core(&cpu_data[cpu], hwid);
+ cpu++;
+ }
+
+ /* Program the shared reset vector with mailbox delivery masked. */
+ reim = read_c0_reim();
+ reim &= ~(REIM_MBOXIRQ(0) | REIM_MBOXIRQ(1));
+ write_c0_reim(reim);
+ write_c0_mailbox0(0);
+ write_c0_mailbox1(0);
+ write_c0_corestatus(0);
+
+ entry = CKSEG1ADDR((unsigned long)xburst_secondary_cpu_entry);
+ write_c0_reim((reim & ~REIM_ENTRY) | (entry & REIM_ENTRY));
+}
+
+static void __init xburst_prepare_cpus(unsigned int max_cpus)
+{
+ struct device_node *np;
+ u32 reim;
+ int ret;
+
+ ret = request_irq(XBURST_MBOX_IRQ, xburst_mbox_interrupt,
+ IRQF_PERCPU | IRQF_NO_THREAD, "core mailbox", NULL);
+ if (ret) {
+ pr_err("XBurst: cannot request mailbox IRQ: %d\n", ret);
+ return;
+ }
+
+ reim = read_c0_reim();
+ write_c0_reim(reim | REIM_MBOXIRQ(0));
+ set_c0_status(STATUSF_IP3);
+ irq_enable_hazard();
+
+ if (!cpu_possible(1))
+ return;
+
+ np = of_get_cpu_node(1, NULL);
+ cpu1_clock = of_clk_get(np, 0);
+ of_node_put(np);
+ if (IS_ERR(cpu1_clock)) {
+ pr_err("XBurst: cannot get CPU1 clock: %ld\n",
+ PTR_ERR(cpu1_clock));
+ return;
+ }
+
+ ret = clk_prepare(cpu1_clock);
+ if (ret) {
+ clk_put(cpu1_clock);
+ cpu1_clock = ERR_PTR(ret);
+ pr_err("XBurst: cannot prepare CPU1 clock: %d\n", ret);
+ }
+}
+
+static int xburst_boot_secondary(int cpu, struct task_struct *idle)
+{
+ unsigned long flags;
+ u32 ctrl;
+ int ret;
+
+ if (cpu_logical_map(cpu) != 1 || IS_ERR_OR_NULL(cpu1_clock))
+ return -ENODEV;
+
+ raw_spin_lock_irqsave(&smp_lock, flags);
+ ctrl = read_c0_corectrl() | CORECTRL_SWRST(1) | CORECTRL_RPC(1);
+ write_c0_corectrl(ctrl);
+ back_to_back_c0_hazard();
+ raw_spin_unlock_irqrestore(&smp_lock, flags);
+
+ ret = clk_enable(cpu1_clock);
+ if (ret)
+ return ret;
+
+ xburst_cpu_entry_sp = __KSTK_TOS(idle);
+ xburst_cpu_entry_gp = (unsigned long)task_thread_info(idle);
+ /* Publish bootstrap state before CPU1 starts using its private cache. */
+ r4k_blast_dcache();
+ /* Complete cache writeback before releasing reset. */
+ mb();
+ raw_spin_lock_irqsave(&smp_lock, flags);
+ ctrl = read_c0_corectrl();
+ write_c0_corectrl(ctrl & ~CORECTRL_SWRST(1));
+ back_to_back_c0_hazard();
+ raw_spin_unlock_irqrestore(&smp_lock, flags);
+ return 0;
+}
+
+static void xburst_init_secondary(void)
+{
+ clear_c0_status(ST0_IM);
+ irq_disable_hazard();
+}
+
+static void xburst_smp_finish(void)
+{
+ unsigned int cpu = cpu_logical_map(smp_processor_id());
+ u32 reim;
+
+ raw_spin_lock(&smp_lock);
+ reim = read_c0_reim();
+ write_c0_reim(reim | REIM_MBOXIRQ(cpu));
+ raw_spin_unlock(&smp_lock);
+
+ change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP2 |
+ STATUSF_IP1 | STATUSF_IP0);
+ irq_enable_hazard();
+ local_irq_enable();
+}
+
+static void xburst_send_ipi_locked(int cpu, unsigned int action)
+{
+ if (cpu_logical_map(cpu) == 0)
+ write_c0_mailbox0(read_c0_mailbox0() | action);
+ else
+ write_c0_mailbox1(read_c0_mailbox1() | action);
+ back_to_back_c0_hazard();
+}
+
+static void xburst_send_ipi_single(int cpu, unsigned int action)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&smp_lock, flags);
+ xburst_send_ipi_locked(cpu, action);
+ raw_spin_unlock_irqrestore(&smp_lock, flags);
+}
+
+static void xburst_send_ipi_mask(const struct cpumask *mask, unsigned int action)
+{
+ unsigned long flags;
+ int cpu;
+
+ raw_spin_lock_irqsave(&smp_lock, flags);
+ for_each_cpu(cpu, mask)
+ xburst_send_ipi_locked(cpu, action);
+ raw_spin_unlock_irqrestore(&smp_lock, flags);
+}
+
+static int __maybe_unused xburst_cpu_disable(void)
+{
+ /* CPU teardown and restart are not supported yet. */
+ return -EOPNOTSUPP;
+}
+
+static const struct plat_smp_ops xburst_smp_ops = {
+ .send_ipi_single = xburst_send_ipi_single,
+ .send_ipi_mask = xburst_send_ipi_mask,
+ .init_secondary = xburst_init_secondary,
+ .smp_finish = xburst_smp_finish,
+ .boot_secondary = xburst_boot_secondary,
+ .smp_setup = xburst_smp_setup,
+ .prepare_cpus = xburst_prepare_cpus,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_disable = xburst_cpu_disable,
+#endif
+};
+
+int __init register_ingenic_smp_ops(void)
+{
+ if (!of_machine_is_compatible("ingenic,jz4780"))
+ return -ENODEV;
+
+ register_smp_ops(&xburst_smp_ops);
+ return 0;
+}
diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c
index 80e8a04a642e..6c44715d81d5 100644
--- a/arch/mips/kernel/idle.c
+++ b/arch/mips/kernel/idle.c
@@ -18,6 +18,7 @@
#include <asm/cpu-type.h>
#include <asm/idle.h>
#include <asm/mipsregs.h>
+#include <asm/r4kcache.h>
/*
* Not all of the MIPS CPUs have the "wait" instruction available. Moreover,
@@ -71,6 +72,28 @@ static void __cpuidle rm7k_wait_irqoff(void)
" .set pop \n");
}
+/* XBurst gates its private cache clock in WAIT; write back dirty data first. */
+static void __cpuidle xburst_wait_irqoff(void)
+{
+ unsigned long pending;
+
+ if (need_resched())
+ return;
+
+ r4k_blast_dcache();
+ /* Recheck work that may have arrived during the cache flush. */
+ pending = read_c0_cause() & read_c0_status() & CAUSEF_IP;
+ if (!need_resched() && !pending) {
+ __asm__ __volatile__(
+ ".set push\n"
+ ".set arch=r4000\n"
+ "sync\n"
+ "wait\n"
+ ".set pop\n"
+ : : : "memory");
+ }
+}
+
/*
* Au1 'wait' is only useful when the 32kHz counter is used as timer,
* since coreclock (and the cp0 counter) stops upon executing it. Only an
@@ -156,10 +179,16 @@ void __init check_wait(void)
case CPU_CAVIUM_OCTEON_PLUS:
case CPU_CAVIUM_OCTEON2:
case CPU_CAVIUM_OCTEON3:
- case CPU_XBURST:
case CPU_LOONGSON32:
cpu_wait = r4k_wait;
break;
+ case CPU_XBURST:
+ if (IS_ENABLED(CONFIG_MACH_JZ4780) &&
+ IS_ENABLED(CONFIG_SMP) && num_possible_cpus() > 1)
+ cpu_wait = xburst_wait_irqoff;
+ else
+ cpu_wait = r4k_wait;
+ break;
case CPU_LOONGSON64:
if ((c->processor_id & (PRID_IMP_MASK | PRID_REV_MASK)) >=
(PRID_IMP_LOONGSON_64C | PRID_REV_LOONGSON3A_R2_0) ||
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