From mboxrd@z Thu Jan 1 00:00:00 1970 From: Icenowy Zheng Date: Wed, 7 Jun 2017 08:47:20 +0800 Subject: [U-Boot] [RFC PATCH 7/8] sunxi: Add basic PSCI implementation for multi-cluster SoCs In-Reply-To: <20170607004721.24194-1-icenowy@aosc.io> References: <20170607004721.24194-1-icenowy@aosc.io> Message-ID: <20170607004721.24194-8-icenowy@aosc.io> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de From: Chen-Yu Tsai Allwinner A80 and A83T SoCs have two clusters of CPU, each cluster contains 4 cores. A80 is Cortex-A15 + Cortex-A7 configuration, while A83T has two clusters of Cortex-A7. This patch adds a basic version that allows bringing up the four cores in the first cluster. The structure is based on existing sunxi PSCI code. Signed-off-by: Chen-Yu Tsai [Icenowy: adapt for A83T] Signed-off-by: Icenowy Zheng --- arch/arm/cpu/armv7/sunxi/Makefile | 4 + arch/arm/cpu/armv7/sunxi/psci-mcpm.c | 258 +++++++++++++++++++++++++++++++++++ 2 files changed, 262 insertions(+) create mode 100644 arch/arm/cpu/armv7/sunxi/psci-mcpm.c diff --git a/arch/arm/cpu/armv7/sunxi/Makefile b/arch/arm/cpu/armv7/sunxi/Makefile index 8c026ff052..c789f686fd 100644 --- a/arch/arm/cpu/armv7/sunxi/Makefile +++ b/arch/arm/cpu/armv7/sunxi/Makefile @@ -14,8 +14,12 @@ obj-$(CONFIG_MACH_SUN8I_H3) += tzpc.o obj-$(CONFIG_MACH_SUN8I_A83T) += tzpc.o ifndef CONFIG_SPL_BUILD +ifdef CONFIG_MACH_SUN8I_A83T +obj-$(CONFIG_ARMV7_PSCI) += psci-mcpm.o +else obj-$(CONFIG_ARMV7_PSCI) += psci.o endif +endif ifdef CONFIG_SPL_BUILD obj-y += fel_utils.o diff --git a/arch/arm/cpu/armv7/sunxi/psci-mcpm.c b/arch/arm/cpu/armv7/sunxi/psci-mcpm.c new file mode 100644 index 0000000000..ba8d669c7e --- /dev/null +++ b/arch/arm/cpu/armv7/sunxi/psci-mcpm.c @@ -0,0 +1,258 @@ +/* + * Copyright (C) 2016 + * Author: Chen-Yu Tsai + * + * Based on assembly code by Marc Zyngier , + * which was based on code by Carl van Schaik . + * + * SPDX-License-Identifier: GPL-2.0 + */ +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +#include + +/* + * NOTE dense CPU IDs (0~3 for first cluster of 4 cores, 4~7 for the + * second cluster) are used throughout the PSCI code. Any MPIDR style + * values must be converted. + */ + +/* + * Provide a dense CPU ID for 2-cluster systems. This must be coded in + * assembly as it gets called from psci_stack_setup, when the stack isn't + * available yet. + * + * Only r0 and r3 is usable. r8 - r12 are available if this function is + * only called from psci_stack_setup, which we cannot guarantee. + */ +u32 __secure __naked psci_get_cpu_id(void) +{ + asm volatile ( + "mrc p15, 0, r3, c0, c0, 5 @ Get MPIDR\n" + "lsr r0, r3, #6\n" + "and r3, r3, #3\n" + "and r0, r0, #4\n" + "orr r0, r0, r3\n" + "bx lr\n" + ); + + /* + * The last five lines are the compiler generated assembly code for + * + * return (reg & 0x3) | (((reg >> 8) & 0x1) << 2); + * + * We can't guarantee that all compilers correctly use only r0 and + * r3, so we use inline assembly here. + */ +} + +static void __secure cp15_write_cntp_tval(u32 tval) +{ + asm volatile ("mcr p15, 0, %0, c14, c2, 0" : : "r" (tval)); +} + +static void __secure cp15_write_cntp_ctl(u32 val) +{ + asm volatile ("mcr p15, 0, %0, c14, c2, 1" : : "r" (val)); +} + +static u32 __secure cp15_read_cntp_ctl(void) +{ + u32 val; + + asm volatile ("mrc p15, 0, %0, c14, c2, 1" : "=r" (val)); + + return val; +} + +#define ONE_US (COUNTER_FREQUENCY / 1000000) + +/* Use a different name to avoid clashing with the non-secure function */ +static void __secure __udelay_sec(unsigned long us) +{ + u32 reg = ONE_US * us; + + cp15_write_cntp_tval(reg); + isb(); + cp15_write_cntp_ctl(3); + + do { + isb(); + reg = cp15_read_cntp_ctl(); + } while (!(reg & BIT(2))); + + cp15_write_cntp_ctl(0); + isb(); +} + +static void __secure clamp_release(u32 *clamp) +{ + writel(0xff, clamp); + __udelay_sec(10); + writel(0xfe, clamp); + __udelay_sec(10); + writel(0xf8, clamp); + __udelay_sec(10); + writel(0xf0, clamp); + __udelay_sec(10); + writel(0x00, clamp); +} + +static void __secure clamp_set(u32 *clamp) +{ + writel(0xff, clamp); +} + +static void __secure sunxi_core_power_switch(u32 *clamp, u32 *pwroff, + bool on, int cpu) +{ + if (on) { + /* Release power clamp */ + clamp_release(clamp); + + __udelay_sec(20); + + /* Clear power gating */ + clrbits_le32(pwroff, BIT(cpu)); + } else { + /* Set power gating */ + setbits_le32(pwroff, BIT(cpu)); + + __udelay_sec(20); + + /* Activate power clamp */ + clamp_set(clamp); + } +} + +static int __secure sunxi_cluster_is_a7(int cluster) +{ +#ifdef CONFIG_MACH_SUN8I_A83T + return 1; +#else + return (clustter == 0); +#endif +} + +static void __secure sunxi_cpu_set_power(int cluster, int cpu, bool on) +{ + struct sunxi_prcm_reg *prcm = + (struct sunxi_prcm_reg *)SUNXI_PRCM_BASE; + + sunxi_core_power_switch(&prcm->cpu_pwr_clamp[cluster][cpu], + &prcm->cpu_pwroff[cluster], on, cpu); +} + +static u32 __secure cp15_read_scr(void) +{ + u32 scr; + + asm volatile ("mrc p15, 0, %0, c1, c1, 0" : "=r" (scr)); + + return scr; +} + +static void __secure cp15_write_scr(u32 scr) +{ + asm volatile ("mcr p15, 0, %0, c1, c1, 0" : : "r" (scr)); + isb(); +} + +int __secure psci_cpu_on(u32 __always_unused unused, u32 mpidr, u32 pc) +{ + struct sunxi_cpucfg_reg *cpucfg = + (struct sunxi_cpucfg_reg *)SUNXI_CPUCFG_BASE; +#ifdef CONFIG_MACH_SUN8I_A83T + struct sunxi_r_cpucfg_reg *r_cpucfg = + (struct sunxi_r_cpucfg_reg *)SUNXI_R_CPUCFG_BASE; +#else + struct sunxi_prcm_reg *prcm = + (struct sunxi_prcm_reg *)SUNXI_PRCM_BASE; +#endif + u32 cluster = (mpidr >> 8) & 0x1; + u32 cpu = mpidr & 0x3; + u32 cpuid = cpu | (cluster << 2); + + /* TODO We don't support multi-cluster yet */ + if (cluster > 0) + return ARM_PSCI_RET_INVAL; + + /* store target PC */ + psci_save_target_pc(cpuid, pc); + + /* Set secondary core power on PC */ +#ifdef CONFIG_MACH_SUN8I_A83T + writel((u32)&psci_cpu_entry, &r_cpucfg->priv0); +#else + writel((u32)&psci_cpu_entry, &prcm->cpu_soft_entry); +#endif + + /* Assert power-on reset on target CPU */ +#ifdef CONFIG_MACH_SUN8I_A83T + clrbits_le32(&r_cpucfg->cpu_rst[cluster], BIT(cpu)); +#else + clrbits_le32(&prcm->cpu_rst[cluster], BIT(cpu)); +#endif + + /* Cortex-A7: hold L1 cache reset disable signal low */ + if (sunxi_cluster_is_a7(cluster)) + clrbits_le32(&cpucfg->cluster[cluster].ctrl0, + CPUCFG_CX_CTRL0_L1_RST_DISABLE(cpu)); + + /* Lock CPU (Disable external debug access) */ + clrbits_le32(&cpucfg->cluster_reset[cluster], + CPUCFG_CX_RST_DBG(cpu)); + + /* Cortex-A7: Assert ETM reset */ + if (sunxi_cluster_is_a7(cluster)) + clrbits_le32(&cpucfg->cluster_reset[cluster], + CPUCFG_CX_RST_ETM(cpu)); + + /* + * Allwinner code also asserts resets for NEON on A15. According + * to ARM manuals, asserting power-on reset is sufficient. + */ + + /* Power up target CPU */ + sunxi_cpu_set_power(cluster, cpu, true); + + /* De-assert power-on reset on target CPU */ +#ifdef CONFIG_MACH_SUN8I_A83T + setbits_le32(&r_cpucfg->cpu_rst[cluster], BIT(cpu)); +#else + setbits_le32(&prcm->cpu_rst[cluster], BIT(cpu)); +#endif + + /* De-assert core reset on target CPU */ + setbits_le32(&cpucfg->cluster_reset[cluster], + CPUCFG_CX_RST_CORE(cpu)); + + /* Cortex-A7: De-assert ETM reset */ + if (sunxi_cluster_is_a7(cluster)) + setbits_le32(&cpucfg->cluster_reset[cluster], + CPUCFG_CX_RST_ETM(cpu)); + + /* Unlock CPU (Disable external debug access) */ + setbits_le32(&cpucfg->cluster_reset[cluster], + CPUCFG_CX_RST_DBG(cpu)); + + return ARM_PSCI_RET_SUCCESS; +} + +void __secure psci_arch_init(void) +{ + u32 reg; + + reg = cp15_read_scr(); + reg &= ~BIT(0); /* Secure mode */ + cp15_write_scr(reg); +} -- 2.12.2