diff options
Diffstat (limited to 'arch/arm/mach-vexpress/spc.c')
| -rw-r--r-- | arch/arm/mach-vexpress/spc.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/arch/arm/mach-vexpress/spc.c b/arch/arm/mach-vexpress/spc.c new file mode 100644 index 000000000000..eefb029197ca --- /dev/null +++ b/arch/arm/mach-vexpress/spc.c @@ -0,0 +1,180 @@ +/* + * Versatile Express Serial Power Controller (SPC) support + * + * Copyright (C) 2013 ARM Ltd. + * + * Authors: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> + * Achin Gupta <achin.gupta@arm.com> + * Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> + * + * 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. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/slab.h> + +#include <asm/cacheflush.h> + +#define SPCLOG "vexpress-spc: " + +/* SPC wake-up IRQs status and mask */ +#define WAKE_INT_MASK 0x24 +#define WAKE_INT_RAW 0x28 +#define WAKE_INT_STAT 0x2c +/* SPC power down registers */ +#define A15_PWRDN_EN 0x30 +#define A7_PWRDN_EN 0x34 +/* SPC per-CPU mailboxes */ +#define A15_BX_ADDR0 0x68 +#define A7_BX_ADDR0 0x78 + +/* wake-up interrupt masks */ +#define GBL_WAKEUP_INT_MSK (0x3 << 10) + +/* TC2 static dual-cluster configuration */ +#define MAX_CLUSTERS 2 + +struct ve_spc_drvdata { + void __iomem *baseaddr; + /* + * A15s cluster identifier + * It corresponds to A15 processors MPIDR[15:8] bitfield + */ + u32 a15_clusid; +}; + +static struct ve_spc_drvdata *info; + +static inline bool cluster_is_a15(u32 cluster) +{ + return cluster == info->a15_clusid; +} + +/** + * ve_spc_global_wakeup_irq() + * + * Function to set/clear global wakeup IRQs. Not protected by locking since + * it might be used in code paths where normal cacheable locks are not + * working. Locking must be provided by the caller to ensure atomicity. + * + * @set: if true, global wake-up IRQs are set, if false they are cleared + */ +void ve_spc_global_wakeup_irq(bool set) +{ + u32 reg; + + reg = readl_relaxed(info->baseaddr + WAKE_INT_MASK); + + if (set) + reg |= GBL_WAKEUP_INT_MSK; + else + reg &= ~GBL_WAKEUP_INT_MSK; + + writel_relaxed(reg, info->baseaddr + WAKE_INT_MASK); +} + +/** + * ve_spc_cpu_wakeup_irq() + * + * Function to set/clear per-CPU wake-up IRQs. Not protected by locking since + * it might be used in code paths where normal cacheable locks are not + * working. Locking must be provided by the caller to ensure atomicity. + * + * @cluster: mpidr[15:8] bitfield describing cluster affinity level + * @cpu: mpidr[7:0] bitfield describing cpu affinity level + * @set: if true, wake-up IRQs are set, if false they are cleared + */ +void ve_spc_cpu_wakeup_irq(u32 cluster, u32 cpu, bool set) +{ + u32 mask, reg; + + if (cluster >= MAX_CLUSTERS) + return; + + mask = 1 << cpu; + + if (!cluster_is_a15(cluster)) + mask <<= 4; + + reg = readl_relaxed(info->baseaddr + WAKE_INT_MASK); + + if (set) + reg |= mask; + else + reg &= ~mask; + + writel_relaxed(reg, info->baseaddr + WAKE_INT_MASK); +} + +/** + * ve_spc_set_resume_addr() - set the jump address used for warm boot + * + * @cluster: mpidr[15:8] bitfield describing cluster affinity level + * @cpu: mpidr[7:0] bitfield describing cpu affinity level + * @addr: physical resume address + */ +void ve_spc_set_resume_addr(u32 cluster, u32 cpu, u32 addr) +{ + void __iomem *baseaddr; + + if (cluster >= MAX_CLUSTERS) + return; + + if (cluster_is_a15(cluster)) + baseaddr = info->baseaddr + A15_BX_ADDR0 + (cpu << 2); + else + baseaddr = info->baseaddr + A7_BX_ADDR0 + (cpu << 2); + + writel_relaxed(addr, baseaddr); +} + +/** + * ve_spc_powerdown() + * + * Function to enable/disable cluster powerdown. Not protected by locking + * since it might be used in code paths where normal cacheable locks are not + * working. Locking must be provided by the caller to ensure atomicity. + * + * @cluster: mpidr[15:8] bitfield describing cluster affinity level + * @enable: if true enables powerdown, if false disables it + */ +void ve_spc_powerdown(u32 cluster, bool enable) +{ + u32 pwdrn_reg; + + if (cluster >= MAX_CLUSTERS) + return; + + pwdrn_reg = cluster_is_a15(cluster) ? A15_PWRDN_EN : A7_PWRDN_EN; + writel_relaxed(enable, info->baseaddr + pwdrn_reg); +} + +int __init ve_spc_init(void __iomem *baseaddr, u32 a15_clusid) +{ + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + pr_err(SPCLOG "unable to allocate mem\n"); + return -ENOMEM; + } + + info->baseaddr = baseaddr; + info->a15_clusid = a15_clusid; + + /* + * Multi-cluster systems may need this data when non-coherent, during + * cluster power-up/power-down. Make sure driver info reaches main + * memory. + */ + sync_cache_w(info); + sync_cache_w(&info); + + return 0; +} |