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[23.128.96.18]) by mx.google.com with ESMTP id c14si1872151edv.4.2020.05.19.07.39.57; Tue, 19 May 2020 07:40:23 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729001AbgESOiQ (ORCPT + 99 others); Tue, 19 May 2020 10:38:16 -0400 Received: from out28-195.mail.aliyun.com ([115.124.28.195]:53382 "EHLO out28-195.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729103AbgESOiQ (ORCPT ); Tue, 19 May 2020 10:38:16 -0400 X-Alimail-AntiSpam: AC=CONTINUE;BC=0.07436282|-1;CH=green;DM=|CONTINUE|false|;DS=CONTINUE|ham_regular_dialog|0.366252-0.00548517-0.628262;FP=0|0|0|0|0|-1|-1|-1;HT=e01a16378;MF=zhouyanjie@wanyeetech.com;NM=1;PH=DS;RN=20;RT=20;SR=0;TI=SMTPD_---.HalgxFh_1589898954; Received: from localhost.localdomain(mailfrom:zhouyanjie@wanyeetech.com fp:SMTPD_---.HalgxFh_1589898954) by smtp.aliyun-inc.com(10.147.42.198); Tue, 19 May 2020 22:36:21 +0800 From: =?UTF-8?q?=E5=91=A8=E7=90=B0=E6=9D=B0=20=28Zhou=20Yanjie=29?= To: linux-mips@vger.kernel.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, tsbogend@alpha.franken.de, paulburton@kernel.org, jiaxun.yang@flygoat.com, chenhc@lemote.com, tglx@linutronix.de, robh+dt@kernel.org, daniel.lezcano@linaro.org, keescook@chromium.org, paul@crapouillou.net, krzk@kernel.org, hns@goldelico.com, ebiederm@xmission.com, dongsheng.qiu@ingenic.com, yanfei.li@ingenic.com, rick.tyliu@ingenic.com, sernia.zhou@foxmail.com, zhenwenjin@gmail.com Subject: [PATCH v8 1/6] MIPS: JZ4780: Introduce SMP support. Date: Tue, 19 May 2020 22:35:18 +0800 Message-Id: <1589898923-60048-3-git-send-email-zhouyanjie@wanyeetech.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1589898923-60048-1-git-send-email-zhouyanjie@wanyeetech.com> References: <1589898923-60048-1-git-send-email-zhouyanjie@wanyeetech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Forward port smp support from kernel 3.18.3 of CI20_linux to upstream kernel 5.6. Tested-by: H. Nikolaus Schaller Tested-by: Paul Boddie Signed-off-by: 周琰杰 (Zhou Yanjie) Reviewed-by: Jiaxun Yang --- Notes: v1->v2: 1.Remove unnecessary "plat_irq_dispatch(void)" in irq-ingenic.c. 2.Add a timeout check for "jz4780_boot_secondary()" to avoid a dead loop. 3.Replace hard code in smp.c with macro. v2->v3: 1.Remove unnecessary "extern void (*r4k_blast_dcache)(void)" in smp.c. 2.Use "for_each_of_cpu_node" instead "for_each_compatible_node" in smp.c. 3.Use "of_cpu_node_to_id" instead "of_property_read_u32_index" in smp.c. 4.Move LCR related operations to jz4780-cgu.c. v3->v4: Rebase on top of kernel 5.6-rc1. v4->v5: 1.Splitting changes involving "jz4780-cgu.c" into separate commit. 2.Use "request_irq()" replace "setup_irq()". v5->v6: In order to have a kernel that works on multiple SoCs at the same time, use "IS_ENABLED()" replace "#ifdef". v6->v7: 1.SMP has be decoupled from the SoC version. 2.Add mailboxes 3 and 4 for XBurst. 3.Adjust code in "jz4780_smp_prepare_cpus()". 4."jz4780_smp_init()" has be marked "__init". v7->v8: No change. arch/mips/include/asm/mach-jz4740/smp.h | 87 +++++++++++ arch/mips/jz4740/Kconfig | 2 + arch/mips/jz4740/Makefile | 5 + arch/mips/jz4740/prom.c | 4 + arch/mips/jz4740/smp-entry.S | 57 +++++++ arch/mips/jz4740/smp.c | 258 ++++++++++++++++++++++++++++++++ arch/mips/kernel/idle.c | 35 ++++- 7 files changed, 447 insertions(+), 1 deletion(-) create mode 100644 arch/mips/include/asm/mach-jz4740/smp.h create mode 100644 arch/mips/jz4740/smp-entry.S create mode 100644 arch/mips/jz4740/smp.c diff --git a/arch/mips/include/asm/mach-jz4740/smp.h b/arch/mips/include/asm/mach-jz4740/smp.h new file mode 100644 index 00000000..86f660f --- /dev/null +++ b/arch/mips/include/asm/mach-jz4740/smp.h @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2013, Paul Burton + * JZ4780 SMP definitions + */ + +#ifndef __MIPS_ASM_MACH_JZ4740_SMP_H__ +#define __MIPS_ASM_MACH_JZ4740_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 read_c0_mailbox2() __read_32bit_c0_register($20, 2) +#define write_c0_mailbox2(val) __write_32bit_c0_register($20, 2, val) + +#define read_c0_mailbox3() __read_32bit_c0_register($20, 3) +#define write_c0_mailbox3(val) __write_32bit_c0_register($20, 3, val) + +#define smp_clr_pending(mask) do { \ + unsigned int stat; \ + stat = read_c0_corestatus(); \ + stat &= ~((mask) & 0xff); \ + write_c0_corestatus(stat); \ + } while (0) + +/* + * Core Control register + */ +#define CORECTRL_SLEEP1M_SHIFT 17 +#define CORECTRL_SLEEP1M (_ULCAST_(0x1) << CORECTRL_SLEEP1M_SHIFT) +#define CORECTRL_SLEEP0M_SHIFT 16 +#define CORECTRL_SLEEP0M (_ULCAST_(0x1) << CORECTRL_SLEEP0M_SHIFT) +#define CORECTRL_RPC1_SHIFT 9 +#define CORECTRL_RPC1 (_ULCAST_(0x1) << CORECTRL_RPC1_SHIFT) +#define CORECTRL_RPC0_SHIFT 8 +#define CORECTRL_RPC0 (_ULCAST_(0x1) << CORECTRL_RPC0_SHIFT) +#define CORECTRL_SWRST1_SHIFT 1 +#define CORECTRL_SWRST1 (_ULCAST_(0x1) << CORECTRL_SWRST1_SHIFT) +#define CORECTRL_SWRST0_SHIFT 0 +#define CORECTRL_SWRST0 (_ULCAST_(0x1) << CORECTRL_SWRST0_SHIFT) + +/* + * Core Status register + */ +#define CORESTATUS_SLEEP1_SHIFT 17 +#define CORESTATUS_SLEEP1 (_ULCAST_(0x1) << CORESTATUS_SLEEP1_SHIFT) +#define CORESTATUS_SLEEP0_SHIFT 16 +#define CORESTATUS_SLEEP0 (_ULCAST_(0x1) << CORESTATUS_SLEEP0_SHIFT) +#define CORESTATUS_IRQ1P_SHIFT 9 +#define CORESTATUS_IRQ1P (_ULCAST_(0x1) << CORESTATUS_IRQ1P_SHIFT) +#define CORESTATUS_IRQ0P_SHIFT 8 +#define CORESTATUS_IRQ0P (_ULCAST_(0x1) << CORESTATUS_IRQ8P_SHIFT) +#define CORESTATUS_MIRQ1P_SHIFT 1 +#define CORESTATUS_MIRQ1P (_ULCAST_(0x1) << CORESTATUS_MIRQ1P_SHIFT) +#define CORESTATUS_MIRQ0P_SHIFT 0 +#define CORESTATUS_MIRQ0P (_ULCAST_(0x1) << CORESTATUS_MIRQ0P_SHIFT) + +/* + * Reset Entry & IRQ Mask register + */ +#define REIM_ENTRY_SHIFT 16 +#define REIM_ENTRY (_ULCAST_(0xffff) << REIM_ENTRY_SHIFT) +#define REIM_IRQ1M_SHIFT 9 +#define REIM_IRQ1M (_ULCAST_(0x1) << REIM_IRQ1M_SHIFT) +#define REIM_IRQ0M_SHIFT 8 +#define REIM_IRQ0M (_ULCAST_(0x1) << REIM_IRQ0M_SHIFT) +#define REIM_MBOXIRQ1M_SHIFT 1 +#define REIM_MBOXIRQ1M (_ULCAST_(0x1) << REIM_MBOXIRQ1M_SHIFT) +#define REIM_MBOXIRQ0M_SHIFT 0 +#define REIM_MBOXIRQ0M (_ULCAST_(0x1) << REIM_MBOXIRQ0M_SHIFT) + +extern void jz4780_smp_init(void); +extern void jz4780_secondary_cpu_entry(void); + +#endif /* __MIPS_ASM_MACH_JZ4740_SMP_H__ */ diff --git a/arch/mips/jz4740/Kconfig b/arch/mips/jz4740/Kconfig index 412d2fa..2b88557 100644 --- a/arch/mips/jz4740/Kconfig +++ b/arch/mips/jz4740/Kconfig @@ -34,9 +34,11 @@ config MACH_JZ4770 config MACH_JZ4780 bool + select GENERIC_CLOCKEVENTS_BROADCAST if SMP select MIPS_CPU_SCACHE select SYS_HAS_CPU_MIPS32_R2 select SYS_SUPPORTS_HIGHMEM + select SYS_SUPPORTS_SMP config MACH_X1000 bool diff --git a/arch/mips/jz4740/Makefile b/arch/mips/jz4740/Makefile index 6de14c0..0a0f024 100644 --- a/arch/mips/jz4740/Makefile +++ b/arch/mips/jz4740/Makefile @@ -12,3 +12,8 @@ CFLAGS_setup.o = -I$(src)/../../../scripts/dtc/libfdt # PM support obj-$(CONFIG_PM) += pm.o + +# SMP support + +obj-$(CONFIG_SMP) += smp.o +obj-$(CONFIG_SMP) += smp-entry.o diff --git a/arch/mips/jz4740/prom.c b/arch/mips/jz4740/prom.c index ff4555c..4acf5c2c 100644 --- a/arch/mips/jz4740/prom.c +++ b/arch/mips/jz4740/prom.c @@ -8,10 +8,14 @@ #include #include +#include void __init prom_init(void) { fw_init_cmdline(); + + if (IS_ENABLED(CONFIG_SMP)) + jz4780_smp_init(); } void __init prom_free_prom_memory(void) diff --git a/arch/mips/jz4740/smp-entry.S b/arch/mips/jz4740/smp-entry.S new file mode 100644 index 00000000..20049a3 --- /dev/null +++ b/arch/mips/jz4740/smp-entry.S @@ -0,0 +1,57 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2013, Paul Burton + * JZ4780 SMP entry point + */ + +#include +#include +#include +#include +#include + +#define CACHE_SIZE (32 * 1024) +#define CACHE_LINESIZE 32 + +.extern jz4780_cpu_entry_sp +.extern jz4780_cpu_entry_gp + +.section .text.smp-entry +.balign 0x10000 +.set noreorder +LEAF(jz4780_secondary_cpu_entry) + mtc0 zero, CP0_CAUSE + + li t0, ST0_CU0 + mtc0 t0, CP0_STATUS + + /* cache setup */ + li t0, KSEG0 + ori t1, t0, CACHE_SIZE + mtc0 zero, CP0_TAGLO, 0 +1: cache Index_Store_Tag_I, 0(t0) + cache Index_Store_Tag_D, 0(t0) + bne t0, t1, 1b + addiu t0, t0, CACHE_LINESIZE + + /* kseg0 cache attribute */ + mfc0 t0, CP0_CONFIG, 0 + ori t0, t0, CONF_CM_CACHABLE_NONCOHERENT + mtc0 t0, CP0_CONFIG, 0 + + /* pagemask */ + mtc0 zero, CP0_PAGEMASK, 0 + + /* retrieve sp */ + la t0, jz4780_cpu_entry_sp + lw sp, 0(t0) + + /* retrieve gp */ + la t0, jz4780_cpu_entry_gp + lw gp, 0(t0) + + /* jump to the kernel in kseg0 */ + la t0, smp_bootstrap + jr t0 + nop + END(jz4780_secondary_cpu_entry) diff --git a/arch/mips/jz4740/smp.c b/arch/mips/jz4740/smp.c new file mode 100644 index 00000000..d95d22a --- /dev/null +++ b/arch/mips/jz4740/smp.c @@ -0,0 +1,258 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2013, Paul Burton + * JZ4780 SMP + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static struct clk *cpu_clock_gates[CONFIG_NR_CPUS] = { NULL }; + +u32 jz4780_cpu_entry_sp; +u32 jz4780_cpu_entry_gp; + +static struct cpumask cpu_running; + +static DEFINE_SPINLOCK(smp_lock); + +static irqreturn_t mbox_handler(int irq, void *dev_id) +{ + int cpu = smp_processor_id(); + u32 action, status; + + spin_lock(&smp_lock); + + switch (cpu) { + case 0: + action = read_c0_mailbox0(); + write_c0_mailbox0(0); + break; + case 1: + action = read_c0_mailbox1(); + write_c0_mailbox1(0); + break; + case 2: + action = read_c0_mailbox2(); + write_c0_mailbox2(0); + break; + case 3: + action = read_c0_mailbox3(); + write_c0_mailbox3(0); + break; + default: + panic("unhandled cpu %d!", cpu); + } + + /* clear pending mailbox interrupt */ + status = read_c0_corestatus(); + status &= ~(CORESTATUS_MIRQ0P << cpu); + write_c0_corestatus(status); + + 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 jz4780_smp_setup(void) +{ + u32 addr, reim; + int cpu; + + reim = read_c0_reim(); + + for (cpu = 0; cpu < NR_CPUS; cpu++) { + __cpu_number_map[cpu] = cpu; + __cpu_logical_map[cpu] = cpu; + set_cpu_possible(cpu, true); + } + + /* mask mailbox interrupts for this core */ + reim &= ~REIM_MBOXIRQ0M; + write_c0_reim(reim); + + /* clear mailboxes & pending mailbox IRQs */ + write_c0_mailbox0(0); + write_c0_mailbox1(0); + write_c0_corestatus(0); + + /* set reset entry point */ + addr = KSEG1ADDR((u32)&jz4780_secondary_cpu_entry); + WARN_ON(addr & ~REIM_ENTRY); + reim &= ~REIM_ENTRY; + reim |= addr & REIM_ENTRY; + + /* unmask mailbox interrupts for this core */ + reim |= REIM_MBOXIRQ0M; + write_c0_reim(reim); + set_c0_status(STATUSF_IP3); + irq_enable_hazard(); + + cpumask_set_cpu(cpu, &cpu_running); +} + +static void jz4780_smp_prepare_cpus(unsigned int max_cpus) +{ + struct device_node *cpu_node; + unsigned cpu, ctrl; + int err; + + /* setup the mailbox IRQ */ + err = request_irq(MIPS_CPU_IRQ_BASE + 3, mbox_handler, + IRQF_PERCPU | IRQF_NO_THREAD, "core mailbox", NULL); + if (err) + pr_err("request_irq() on core mailbox failed\n"); + + ctrl = read_c0_corectrl(); + + for_each_of_cpu_node(cpu_node) { + cpu = of_cpu_node_to_id(cpu_node); + if (cpu < 0) { + pr_err("Failed to read index of %s\n", + cpu_node->full_name); + continue; + } + + /* use reset entry point from REIM register */ + ctrl |= CORECTRL_RPC0 << cpu; + + cpu_clock_gates[cpu] = of_clk_get(cpu_node, 0); + if (IS_ERR(cpu_clock_gates[cpu])) { + cpu_clock_gates[cpu] = NULL; + continue; + } + + err = clk_prepare(cpu_clock_gates[cpu]); + if (err) + pr_err("Failed to prepare CPU clock gate\n"); + } + + write_c0_corectrl(ctrl); +} + +static int jz4780_boot_secondary(int cpu, struct task_struct *idle) +{ + unsigned long flags; + u32 ctrl; + + spin_lock_irqsave(&smp_lock, flags); + + /* ensure the core is in reset */ + ctrl = read_c0_corectrl(); + ctrl |= CORECTRL_SWRST0 << cpu; + write_c0_corectrl(ctrl); + + /* ungate core clock */ + if (cpu_clock_gates[cpu]) + clk_enable(cpu_clock_gates[cpu]); + + /* set entry sp/gp register values */ + jz4780_cpu_entry_sp = __KSTK_TOS(idle); + jz4780_cpu_entry_gp = (u32)task_thread_info(idle); + smp_wmb(); + + /* take the core out of reset */ + ctrl &= ~(CORECTRL_SWRST0 << cpu); + write_c0_corectrl(ctrl); + + cpumask_set_cpu(cpu, &cpu_running); + + spin_unlock_irqrestore(&smp_lock, flags); + + return 0; +} + +static void jz4780_init_secondary(void) +{ +} + +static void jz4780_smp_finish(void) +{ + u32 reim; + + spin_lock(&smp_lock); + + /* unmask mailbox interrupts for this core */ + reim = read_c0_reim(); + reim |= REIM_MBOXIRQ0M << smp_processor_id(); + write_c0_reim(reim); + + spin_unlock(&smp_lock); + + /* unmask interrupts for this core */ + change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP2 | + STATUSF_IP1 | STATUSF_IP0); + irq_enable_hazard(); + + /* force broadcast timer */ + tick_broadcast_force(); +} + +static void jz4780_send_ipi_single_locked(int cpu, unsigned int action) +{ + u32 mbox; + + switch (cpu) { + case 0: + mbox = read_c0_mailbox0(); + write_c0_mailbox0(mbox | action); + break; + case 1: + mbox = read_c0_mailbox1(); + write_c0_mailbox1(mbox | action); + break; + default: + panic("unhandled cpu %d!", cpu); + } +} + +static void jz4780_send_ipi_single(int cpu, unsigned int action) +{ + unsigned long flags; + + spin_lock_irqsave(&smp_lock, flags); + jz4780_send_ipi_single_locked(cpu, action); + spin_unlock_irqrestore(&smp_lock, flags); +} + +static void jz4780_send_ipi_mask(const struct cpumask *mask, + unsigned int action) +{ + unsigned long flags; + int cpu; + + spin_lock_irqsave(&smp_lock, flags); + + for_each_cpu(cpu, mask) + jz4780_send_ipi_single_locked(cpu, action); + + spin_unlock_irqrestore(&smp_lock, flags); +} + +static struct plat_smp_ops jz4780_smp_ops = { + .send_ipi_single = jz4780_send_ipi_single, + .send_ipi_mask = jz4780_send_ipi_mask, + .init_secondary = jz4780_init_secondary, + .smp_finish = jz4780_smp_finish, + .boot_secondary = jz4780_boot_secondary, + .smp_setup = jz4780_smp_setup, + .prepare_cpus = jz4780_smp_prepare_cpus, +}; + +void __init jz4780_smp_init(void) +{ + register_smp_ops(&jz4780_smp_ops); +} diff --git a/arch/mips/kernel/idle.c b/arch/mips/kernel/idle.c index 37f8e78..d33f2d4 100644 --- a/arch/mips/kernel/idle.c +++ b/arch/mips/kernel/idle.c @@ -18,6 +18,7 @@ #include #include #include +#include /* * Not all of the MIPS CPUs have the "wait" instruction available. Moreover, @@ -88,6 +89,34 @@ static void __cpuidle rm7k_wait_irqoff(void) } /* + * The Ingenic jz4780 SMP variant has to write back dirty cache lines before + * executing wait. The CPU & cache clock will be gated until we return from + * the wait, and if another core attempts to access data from our data cache + * during this time then it will lock up. + */ +void jz4780_smp_wait_irqoff(void) +{ + unsigned long pending = read_c0_cause() & read_c0_status() & CAUSEF_IP; + + /* + * Going to idle has a significant overhead due to the cache flush so + * try to avoid it if we'll immediately be woken again due to an IRQ. + */ + if (!need_resched() && !pending) { + r4k_blast_dcache(); + + __asm__( + " .set push \n" + " .set mips3 \n" + " sync \n" + " wait \n" + " .set pop \n"); + } + + local_irq_enable(); +} + +/* * 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 * interrupt can wake it, so they must be enabled before entering idle modes. @@ -172,7 +201,6 @@ void __init check_wait(void) case CPU_CAVIUM_OCTEON_PLUS: case CPU_CAVIUM_OCTEON2: case CPU_CAVIUM_OCTEON3: - case CPU_XBURST: case CPU_LOONGSON32: case CPU_XLR: case CPU_XLP: @@ -246,6 +274,11 @@ void __init check_wait(void) cpu_wait = r4k_wait; */ break; + case CPU_XBURST: + if (IS_ENABLED(CONFIG_SMP)) + cpu_wait = jz4780_smp_wait_irqoff; + else + cpu_wait = r4k_wait; default: break; } -- 2.7.4