Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756924Ab2EKLxt (ORCPT ); Fri, 11 May 2012 07:53:49 -0400 Received: from am1ehsobe003.messaging.microsoft.com ([213.199.154.206]:16689 "EHLO am1outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751071Ab2EKLxs (ORCPT ); Fri, 11 May 2012 07:53:48 -0400 X-SpamScore: 0 X-BigFish: VS0(zzzz1202hzz8275bhz2dh2a8h668h839hd24he5bh) X-Forefront-Antispam-Report: CIP:70.37.183.190;KIP:(null);UIP:(null);IPV:NLI;H:mail.freescale.net;RD:none;EFVD:NLI From: Zhao Chenhui To: CC: , , , Subject: [PATCH v5 1/5] powerpc/85xx: implement hardware timebase sync Date: Fri, 11 May 2012 19:53:51 +0800 Message-ID: <1336737235-15370-1-git-send-email-chenhui.zhao@freescale.com> X-Mailer: git-send-email 1.6.4.1 MIME-Version: 1.0 Content-Type: text/plain X-OriginatorOrg: freescale.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4215 Lines: 163 Do hardware timebase sync. Firstly, stop all timebases, and transfer the timebase value of the boot core to the other core. Finally, start all timebases. Only apply to dual-core chips, such as MPC8572, P2020, etc. Signed-off-by: Zhao Chenhui Signed-off-by: Li Yang --- arch/powerpc/include/asm/fsl_guts.h | 2 + arch/powerpc/platforms/85xx/smp.c | 93 +++++++++++++++++++++++++++++++++-- 2 files changed, 91 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/include/asm/fsl_guts.h b/arch/powerpc/include/asm/fsl_guts.h index aa4c488..dd5ba2c 100644 --- a/arch/powerpc/include/asm/fsl_guts.h +++ b/arch/powerpc/include/asm/fsl_guts.h @@ -48,6 +48,8 @@ struct ccsr_guts { __be32 dmuxcr; /* 0x.0068 - DMA Mux Control Register */ u8 res06c[0x70 - 0x6c]; __be32 devdisr; /* 0x.0070 - Device Disable Control */ +#define CCSR_GUTS_DEVDISR_TB1 0x00001000 +#define CCSR_GUTS_DEVDISR_TB0 0x00004000 __be32 devdisr2; /* 0x.0074 - Device Disable Control 2 */ u8 res078[0x7c - 0x78]; __be32 pmjcr; /* 0x.007c - 4 Power Management Jog Control Register */ diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c index ff42490..6862dda 100644 --- a/arch/powerpc/platforms/85xx/smp.c +++ b/arch/powerpc/platforms/85xx/smp.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -115,13 +116,70 @@ smp_85xx_kick_cpu(int nr) struct smp_ops_t smp_85xx_ops = { .kick_cpu = smp_85xx_kick_cpu, -#ifdef CONFIG_KEXEC - .give_timebase = smp_generic_give_timebase, - .take_timebase = smp_generic_take_timebase, -#endif }; #ifdef CONFIG_KEXEC +static struct ccsr_guts __iomem *guts; +static u64 timebase; +static int tb_req; +static int tb_valid; + +static void mpc85xx_timebase_freeze(int freeze) +{ + unsigned int mask; + + if (!guts) + return; + + mask = CCSR_GUTS_DEVDISR_TB0 | CCSR_GUTS_DEVDISR_TB1; + if (freeze) + setbits32(&guts->devdisr, mask); + else + clrbits32(&guts->devdisr, mask); + + in_be32(&guts->devdisr); +} + +static void mpc85xx_give_timebase(void) +{ + unsigned long flags; + + local_irq_save(flags); + + while (!tb_req) + barrier(); + tb_req = 0; + + mpc85xx_timebase_freeze(1); + timebase = get_tb(); + mb(); + tb_valid = 1; + + while (tb_valid) + barrier(); + + mpc85xx_timebase_freeze(0); + + local_irq_restore(flags); +} + +static void mpc85xx_take_timebase(void) +{ + unsigned long flags; + + local_irq_save(flags); + + tb_req = 1; + while (!tb_valid) + barrier(); + + set_tb(timebase >> 32, timebase & 0xffffffff); + mb(); + tb_valid = 0; + + local_irq_restore(flags); +} + atomic_t kexec_down_cpus = ATOMIC_INIT(0); void mpc85xx_smp_kexec_cpu_down(int crash_shutdown, int secondary) @@ -228,6 +286,20 @@ smp_85xx_setup_cpu(int cpu_nr) doorbell_setup_this_cpu(); } +#ifdef CONFIG_KEXEC +static const struct of_device_id guts_ids[] = { + { .compatible = "fsl,mpc8572-guts", }, + { .compatible = "fsl,mpc8560-guts", }, + { .compatible = "fsl,mpc8536-guts", }, + { .compatible = "fsl,p1020-guts", }, + { .compatible = "fsl,p1021-guts", }, + { .compatible = "fsl,p1022-guts", }, + { .compatible = "fsl,p1023-guts", }, + { .compatible = "fsl,p2020-guts", }, + {}, +}; +#endif + void __init mpc85xx_smp_init(void) { struct device_node *np; @@ -249,6 +321,19 @@ void __init mpc85xx_smp_init(void) smp_85xx_ops.cause_ipi = doorbell_cause_ipi; } +#ifdef CONFIG_KEXEC + np = of_find_matching_node(NULL, guts_ids); + if (np) { + guts = of_iomap(np, 0); + smp_85xx_ops.give_timebase = mpc85xx_give_timebase; + smp_85xx_ops.take_timebase = mpc85xx_take_timebase; + of_node_put(np); + } else { + smp_85xx_ops.give_timebase = smp_generic_give_timebase; + smp_85xx_ops.take_timebase = smp_generic_take_timebase; + } +#endif + smp_ops = &smp_85xx_ops; #ifdef CONFIG_KEXEC -- 1.6.4.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/