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Wed, 14 May 2014 16:23:18 +0900 (KST) From: Abhilash Kesavan To: linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kgene.kim@samsung.com, abrestic@chromium.org, thomas.ab@samsung.com, inderpal.s@samsung.com, lorenzo.pieralisi@arm.com, nicolas.pitre@linaro.org, Dave.Martin@arm.com, t.figa@samsung.com Subject: [PATCH v7 5/5] arm: exynos: Add MCPM call-back functions Date: Wed, 14 May 2014 12:54:37 +0530 Message-id: <1400052277-3349-1-git-send-email-a.kesavan@samsung.com> X-Mailer: git-send-email 1.7.9.5 In-reply-to: <1399982324-27879-6-git-send-email-a.kesavan@samsung.com> References: <1399982324-27879-6-git-send-email-a.kesavan@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupmkeLIzCtJLcpLzFFi42JZI2JSq/tcsjjY4NRdFovHaxYzWax8/5fR omnuHkaL3fe+MFr0LrjKZrHp8TVWixnn9zFZvPn9gt3i07N/7BbrZ7xmsehYxujA7bFm3hpG j9kNF1k87lzbw+axeUm9R9+WVYwenzfJBbBFcdmkpOZklqUW6dslcGWceTCDpeBvYsXl1VdZ Ghi3+HcxcnBICJhI3HjB2sXICWSKSVy4t56ti5GLQ0hgKaPEzt0PmGBqDm1wgIhPZ5SY2fiP CcLpY5KYPfUBWDebgJ7Egn9fmUESIgI9TBJr97SwgCSYBXQkNsxfD2YLCzhK7P2ymRHEZhFQ lWjbOZ8JxOYVcJE4cOsn1DYFiTmTbEBMTgE3iSNbxUEqhARcJV6e3MYOMl5C4BC7xLuN75gg xghIfJt8iAWiVVZi0wFmiGckJQ6uuMEygVF4ASPDKkbR1ILkguKk9CITveLE3OLSvHS95Pzc TYzAiDj979mEHYz3DlgfYkwGGjeRWUo0OR8YUXkl8YbGZkYWpiamxkbmlmakCSuJ86o9SgoS EkhPLEnNTk0tSC2KLyrNSS0+xMjEwSnVwGi84Kj28XmKhvFiFtNNy1Ri1j9X3Hqotm/2Vr17 CRc0GZ/vzPs45/Sls1wPOJjLrh1R9nluLhzLUmHIWMjNqbP1yoGtZzM/zFnPf6fHl3PDyfrz z3pzBMO3fhficvrQGMnYv5Tl/mqFgiy3IP/446JmvkZPihkF1r1lO5zMYWYauVzVS+XPbSWW 4oxEQy3mouJEAHxJWvSeAgAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrJIsWRmVeSWpSXmKPExsVy+t9jQd1nksXBBo23TS0er1nMZLHy/V9G i6a5exgtdt/7wmjRu+Aqm8Wmx9dYLWac38dk8eb3C3aLT8/+sVusn/GaxaJjGaMDt8eaeWsY PWY3XGTxuHNtD5vH5iX1Hn1bVjF6fN4kF8AW1cBok5GamJJapJCal5yfkpmXbqvkHRzvHG9q ZmCoa2hpYa6kkJeYm2qr5OIToOuWmQN0npJCWWJOKVAoILG4WEnfDtOE0BA3XQuYxghd35Ag uB4jAzSQsIYx48yDGSwFfxMrLq++ytLAuMW/i5GDQ0LAROLQBocuRk4gU0ziwr31bF2MXBxC AtMZJWY2/mOCcPqYJGZPfcAKUsUmoCex4N9XZpCEiEAPk8TaPS0sIAlmAR2JDfPXg9nCAo4S e79sZgSxWQRUJdp2zmcCsXkFXCQO3PrJBLFZQWLOJBsQk1PATeLIVnGQCiEBV4mXJ7exT2Dk XcDIsIpRNLUguaA4KT3XUK84Mbe4NC9dLzk/dxMjOOKeSe1gXNlgcYhRgINRiYf3hnNRsBBr YllxZe4hRgkOZiUR3vItQCHelMTKqtSi/Pii0pzU4kOMyUA3TWSWEk3OByaDvJJ4Q2MTc1Nj U0sTCxMzS9KElcR5D7RaBwoJpCeWpGanphakFsFsYeLglGpgLBMxFS/Iytn5Ii31YcFKDu0w sf7pYa0sbo26PxQeHVnQt/fwdLbvi06mu9a/l93Z9DVpwoojM2zXxPlv+2PcbmL1IeL8D+6L zsJ5W7f/apVcMe3r0bm3J+ss27qgJKhTvkf+FTer81rNnqudQSFpZ7OeO/2911zetpL/KJeI xs6bsU5vuve/UWIpzkg01GIuKk4EADuUeqf8AgAA DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140514_002342_057759_C35A38C1 X-CRM114-Status: GOOD ( 26.20 ) X-Spam-Score: -5.7 (-----) Cc: Abhilash Kesavan X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add machine-dependent MCPM call-backs for Exynos5420. These are used to power up/down the secondary CPUs during boot, shutdown, s2r and switching. Signed-off-by: Thomas Abraham Signed-off-by: Inderpal Singh Signed-off-by: Andrew Bresticker Signed-off-by: Abhilash Kesavan Reviewed-by: Nicolas Pitre --- Changes since v6: Addressed the following comments from Lorenzo Pieralisi: - Added a comment for the power down function suggested by Lorenzo. - Unmapped the non-secure sram region after use. - Removed unnecessary variable initialization. arch/arm/mach-exynos/Kconfig | 8 + arch/arm/mach-exynos/Makefile | 2 + arch/arm/mach-exynos/mcpm-exynos.c | 351 ++++++++++++++++++++++++++++++++++++ arch/arm/mach-exynos/regs-pmu.h | 3 + 4 files changed, 364 insertions(+) create mode 100644 arch/arm/mach-exynos/mcpm-exynos.c diff --git a/arch/arm/mach-exynos/Kconfig b/arch/arm/mach-exynos/Kconfig index fc8bf18..1602abc 100644 --- a/arch/arm/mach-exynos/Kconfig +++ b/arch/arm/mach-exynos/Kconfig @@ -110,4 +110,12 @@ config SOC_EXYNOS5440 endmenu +config EXYNOS5420_MCPM + bool "Exynos5420 Multi-Cluster PM support" + depends on MCPM && SOC_EXYNOS5420 + select ARM_CCI + help + This is needed to provide CPU and cluster power management + on Exynos5420 implementing big.LITTLE. + endif diff --git a/arch/arm/mach-exynos/Makefile b/arch/arm/mach-exynos/Makefile index f6dcc25..2e0666d 100644 --- a/arch/arm/mach-exynos/Makefile +++ b/arch/arm/mach-exynos/Makefile @@ -24,3 +24,5 @@ obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o plus_sec := $(call as-instr,.arch_extension sec,+sec) AFLAGS_exynos-smc.o :=-Wa,-march=armv7-a$(plus_sec) + +obj-$(CONFIG_EXYNOS5420_MCPM) += mcpm-exynos.o diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c new file mode 100644 index 0000000..7d271e7 --- /dev/null +++ b/arch/arm/mach-exynos/mcpm-exynos.c @@ -0,0 +1,351 @@ +/* + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * http://www.samsung.com + * + * arch/arm/mach-exynos/mcpm-exynos.c + * + * Based on arch/arm/mach-vexpress/dcscb.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include + +#include +#include +#include + +#include "regs-pmu.h" +#include "common.h" + +#define EXYNOS5420_CPUS_PER_CLUSTER 4 +#define EXYNOS5420_NR_CLUSTERS 2 +#define MCPM_BOOT_ADDR_OFFSET 0x1c + +/* + * The common v7_exit_coherency_flush API could not be used because of the + * Erratum 799270 workaround. This macro is the same as the common one (in + * arch/arm/include/asm/cacheflush.h) except for the erratum handling. + */ +#define exynos_v7_exit_coherency_flush(level) \ + asm volatile( \ + "stmfd sp!, {fp, ip}\n\t"\ + "mrc p15, 0, r0, c1, c0, 0 @ get SCTLR\n\t" \ + "bic r0, r0, #"__stringify(CR_C)"\n\t" \ + "mcr p15, 0, r0, c1, c0, 0 @ set SCTLR\n\t" \ + "isb\n\t"\ + "bl v7_flush_dcache_"__stringify(level)"\n\t" \ + "clrex\n\t"\ + "mrc p15, 0, r0, c1, c0, 1 @ get ACTLR\n\t" \ + "bic r0, r0, #(1 << 6) @ disable local coherency\n\t" \ + /* Dummy Load of a device register to avoid Erratum 799270 */ \ + "ldr r4, [%0]\n\t" \ + "and r4, r4, #0\n\t" \ + "orr r0, r0, r4\n\t" \ + "mcr p15, 0, r0, c1, c0, 1 @ set ACTLR\n\t" \ + "isb\n\t" \ + "dsb\n\t" \ + "ldmfd sp!, {fp, ip}" \ + : \ + : "Ir" (S5P_INFORM0) \ + : "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \ + "r9", "r10", "lr", "memory") + +/* + * We can't use regular spinlocks. In the switcher case, it is possible + * for an outbound CPU to call power_down() after its inbound counterpart + * is already live using the same logical CPU number which trips lockdep + * debugging. + */ +static arch_spinlock_t exynos_mcpm_lock = __ARCH_SPIN_LOCK_UNLOCKED; +static int +cpu_use_count[EXYNOS5420_CPUS_PER_CLUSTER][EXYNOS5420_NR_CLUSTERS]; + +#define exynos_cluster_usecnt(cluster) \ + (cpu_use_count[0][cluster] + \ + cpu_use_count[1][cluster] + \ + cpu_use_count[2][cluster] + \ + cpu_use_count[3][cluster]) + +#define exynos_cluster_unused(cluster) !exynos_cluster_usecnt(cluster) + +static int exynos_cluster_power_control(unsigned int cluster, int enable) +{ + unsigned int tries = 100; + unsigned int val; + + if (enable) { + exynos_cluster_power_up(cluster); + val = S5P_CORE_LOCAL_PWR_EN; + } else { + exynos_cluster_power_down(cluster); + val = 0; + } + + /* Wait until cluster power control is applied */ + while (tries--) { + if (exynos_cluster_power_state(cluster) == val) + return 0; + + cpu_relax(); + } + pr_debug("timed out waiting for cluster %u to power %s\n", cluster, + enable ? "on" : "off"); + + return -ETIMEDOUT; +} + +static int exynos_power_up(unsigned int cpu, unsigned int cluster) +{ + unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER); + int err = 0; + + pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); + if (cpu >= EXYNOS5420_CPUS_PER_CLUSTER || + cluster >= EXYNOS5420_NR_CLUSTERS) + return -EINVAL; + + /* + * Since this is called with IRQs enabled, and no arch_spin_lock_irq + * variant exists, we need to disable IRQs manually here. + */ + local_irq_disable(); + arch_spin_lock(&exynos_mcpm_lock); + + cpu_use_count[cpu][cluster]++; + if (cpu_use_count[cpu][cluster] == 1) { + bool was_cluster_down = + (exynos_cluster_usecnt(cluster) == 1); + + /* + * Turn on the cluster (L2/COMMON) and then power on the + * cores. + */ + if (was_cluster_down) + err = exynos_cluster_power_control(cluster, 1); + + if (!err) + exynos_cpu_power_up(cpunr); + else + exynos_cluster_power_control(cluster, 0); + } else if (cpu_use_count[cpu][cluster] != 2) { + /* + * The only possible values are: + * 0 = CPU down + * 1 = CPU (still) up + * 2 = CPU requested to be up before it had a chance + * to actually make itself down. + * Any other value is a bug. + */ + BUG(); + } + + arch_spin_unlock(&exynos_mcpm_lock); + local_irq_enable(); + + return err; +} + +/* + * NOTE: This function requires the stack data to be visible through power down + * and can only be executed on processors like A15 and A7 that hit the cache + * with the C bit clear in the SCTLR register. + */ +static void exynos_power_down(void) +{ + unsigned int mpidr, cpu, cluster; + bool last_man = false, skip_wfi = false; + unsigned int cpunr; + + mpidr = read_cpuid_mpidr(); + cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); + cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); + cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER); + + pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); + BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER || + cluster >= EXYNOS5420_NR_CLUSTERS); + + __mcpm_cpu_going_down(cpu, cluster); + + arch_spin_lock(&exynos_mcpm_lock); + BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP); + cpu_use_count[cpu][cluster]--; + if (cpu_use_count[cpu][cluster] == 0) { + exynos_cpu_power_down(cpunr); + + if (exynos_cluster_unused(cluster)) + /* TODO: Turn off the cluster here to save power. */ + last_man = true; + } else if (cpu_use_count[cpu][cluster] == 1) { + /* + * A power_up request went ahead of us. + * Even if we do not want to shut this CPU down, + * the caller expects a certain state as if the WFI + * was aborted. So let's continue with cache cleaning. + */ + skip_wfi = true; + } else { + BUG(); + } + + if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) { + arch_spin_unlock(&exynos_mcpm_lock); + + if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A15) { + /* + * On the Cortex-A15 we need to disable + * L2 prefetching before flushing the cache. + */ + asm volatile( + "mcr p15, 1, %0, c15, c0, 3\n\t" + "isb\n\t" + "dsb" + : : "r" (0x400)); + } + + /* Flush all cache levels for this cluster. */ + exynos_v7_exit_coherency_flush(all); + + /* + * Disable cluster-level coherency by masking + * incoming snoops and DVM messages: + */ + cci_disable_port_by_cpu(mpidr); + + __mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN); + } else { + arch_spin_unlock(&exynos_mcpm_lock); + + /* Disable and flush the local CPU cache. */ + exynos_v7_exit_coherency_flush(louis); + } + + __mcpm_cpu_down(cpu, cluster); + + /* Now we are prepared for power-down, do it: */ + if (!skip_wfi) + wfi(); + + /* Not dead at this point? Let our caller cope. */ +} + +static int exynos_power_down_finish(unsigned int cpu, unsigned int cluster) +{ + unsigned int tries = 100; + unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER); + + pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); + BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER || + cluster >= EXYNOS5420_NR_CLUSTERS); + + /* Wait for the core state to be OFF */ + while (tries--) { + if (ACCESS_ONCE(cpu_use_count[cpu][cluster]) == 0) { + if ((exynos_cpu_power_state(cpunr) == 0)) + return 0; /* success: the CPU is halted */ + } + + /* Otherwise, wait and retry: */ + msleep(1); + } + + return -ETIMEDOUT; /* timeout */ +} + +static const struct mcpm_platform_ops exynos_power_ops = { + .power_up = exynos_power_up, + .power_down = exynos_power_down, + .power_down_finish = exynos_power_down_finish, +}; + +static void __init exynos_mcpm_usage_count_init(void) +{ + unsigned int mpidr, cpu, cluster; + + mpidr = read_cpuid_mpidr(); + cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); + cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); + + pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster); + BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER || + cluster >= EXYNOS5420_NR_CLUSTERS); + + cpu_use_count[cpu][cluster] = 1; +} + +/* + * Enable cluster-level coherency, in preparation for turning on the MMU. + */ +static void __naked exynos_pm_power_up_setup(unsigned int affinity_level) +{ + asm volatile ("\n" + "cmp r0, #1\n" + "bxne lr\n" + "b cci_enable_port_for_self"); +} + +static int __init exynos_mcpm_init(void) +{ + struct device_node *node; + void __iomem *ns_sram_base_addr; + int ret; + + node = of_find_compatible_node(NULL, NULL, "samsung,exynos5420"); + if (!node) + return -ENODEV; + of_node_put(node); + + if (!cci_probed()) + return -ENODEV; + + node = of_find_compatible_node(NULL, NULL, + "samsung,exynos4210-sysram-ns"); + if (!node) + return -ENODEV; + + ns_sram_base_addr = of_iomap(node, 0); + of_node_put(node); + if (!ns_sram_base_addr) { + pr_err("failed to map non-secure iRAM base address\n"); + return -ENOMEM; + } + + /* + * To increase the stability of KFC reset we need to program + * the PMU SPARE3 register + */ + __raw_writel(EXYNOS5420_SWRESET_KFC_SEL, S5P_PMU_SPARE3); + + exynos_mcpm_usage_count_init(); + + ret = mcpm_platform_register(&exynos_power_ops); + if (!ret) + ret = mcpm_sync_init(exynos_pm_power_up_setup); + if (ret) { + iounmap(ns_sram_base_addr); + return ret; + } + + mcpm_smp_set_ops(); + + pr_info("Exynos MCPM support installed\n"); + + /* + * Future entries into the kernel can now go + * through the cluster entry vectors. + */ + __raw_writel(virt_to_phys(mcpm_entry_point), + ns_sram_base_addr + MCPM_BOOT_ADDR_OFFSET); + + iounmap(ns_sram_base_addr); + + return ret; +} + +early_initcall(exynos_mcpm_init); diff --git a/arch/arm/mach-exynos/regs-pmu.h b/arch/arm/mach-exynos/regs-pmu.h index f6b68a3..4179f6a 100644 --- a/arch/arm/mach-exynos/regs-pmu.h +++ b/arch/arm/mach-exynos/regs-pmu.h @@ -38,6 +38,7 @@ #define S5P_INFORM5 S5P_PMUREG(0x0814) #define S5P_INFORM6 S5P_PMUREG(0x0818) #define S5P_INFORM7 S5P_PMUREG(0x081C) +#define S5P_PMU_SPARE3 S5P_PMUREG(0x090C) #define S5P_ARM_CORE0_LOWPWR S5P_PMUREG(0x1000) #define S5P_DIS_IRQ_CORE0 S5P_PMUREG(0x1004) @@ -322,4 +323,6 @@ #define EXYNOS5_OPTION_USE_RETENTION (1 << 4) +#define EXYNOS5420_SWRESET_KFC_SEL 0x3 + #endif /* __ASM_ARCH_REGS_PMU_H */