new file mode 100644
@@ -0,0 +1,36 @@
+* ARM Versatile Express Serial Power Controller device tree bindings
+
+Latest ARM development boards implement a power management interface (serial
+power controller - SPC) that is capable of managing power states transitions,
+wake-up IRQs and resume addresses for ARM multiprocessor testchips.
+The serial controller can be programmed through a memory mapped interface
+that enables communication between firmware running on the microcontroller
+managing power states and the application processors.
+
+The SPC DT bindings are defined as follows:
+
+- spc node
+
+ - compatible:
+ Usage: required
+ Value type: <stringlist>
+ Definition: must be
+ "arm,vexpress-spc,v2p-ca15_a7", "arm,vexpress-spc"
+ - reg:
+ Usage: required
+ Value type: <prop-encode-array>
+ Definition: A standard property that specifies the base address
+ and the size of the SPC address space
+ - interrupts:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: SPC interrupt configuration. A standard property
+ that follows ePAPR interrupts specifications
+
+Example:
+
+spc: spc@7fff0000 {
+ compatible = "arm,vexpress-spc,v2p-ca15_a7", "arm,vexpress-spc";
+ reg = <0x7fff0000 0x1000>;
+ interrupts = <0 95 4>;
+};
@@ -4,4 +4,6 @@ endif
if GOLDFISH
source "drivers/platform/goldfish/Kconfig"
endif
-
+if ARCH_VEXPRESS
+source "drivers/platform/vexpress/Kconfig"
+endif
@@ -5,3 +5,4 @@
obj-$(CONFIG_X86) += x86/
obj-$(CONFIG_OLPC) += olpc/
obj-$(CONFIG_GOLDFISH) += goldfish/
+obj-$(CONFIG_ARCH_VEXPRESS) += vexpress/
new file mode 100644
@@ -0,0 +1,9 @@
+config VEXPRESS_SPC
+ bool "Versatile Express SPC driver support"
+ help
+ The Serial Power Controller (SPC) for ARM Ltd. test chips, is
+ an IP that provides a memory mapped interface to power controller
+ HW. The driver provides an API abstraction meant to be used by
+ subsystem drivers allowing to program registers controlling
+ low-level power management features like power down flags,
+ global and per-cpu wake-up IRQs.
new file mode 100644
@@ -0,0 +1 @@
+obj-$(CONFIG_VEXPRESS_SPC) += spc.o
new file mode 100644
@@ -0,0 +1,253 @@
+/*
+ * 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/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/vexpress.h>
+
+#include <asm/cacheflush.h>
+
+#define SPCLOG "vexpress-spc: "
+
+/* SCC conf registers */
+#define A15_CONF 0x400
+#define SYS_INFO 0x700
+
+/* SPC registers base */
+#define SPC_BASE 0xB00
+
+/* SPC wake-up IRQs status and mask */
+#define WAKE_INT_MASK (SPC_BASE + 0x24)
+#define WAKE_INT_RAW (SPC_BASE + 0x28)
+#define WAKE_INT_STAT (SPC_BASE + 0x2c)
+/* SPC power down registers */
+#define A15_PWRDN_EN (SPC_BASE + 0x30)
+#define A7_PWRDN_EN (SPC_BASE + 0x34)
+/* SPC per-CPU mailboxes */
+#define A15_BX_ADDR0 (SPC_BASE + 0x68)
+#define A7_BX_ADDR0 (SPC_BASE + 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_get_nr_cpus() - get number of cpus in a cluster
+ *
+ * @cluster: mpidr[15:8] bitfield describing cluster affinity level
+ *
+ * Return: > 0 number of cpus in the cluster
+ * or 0 if cluster number invalid
+ */
+u32 ve_spc_get_nr_cpus(u32 cluster)
+{
+ u32 val;
+
+ if (cluster >= MAX_CLUSTERS)
+ return 0;
+
+ val = readl_relaxed(info->baseaddr + SYS_INFO);
+ val = cluster_is_a15(cluster) ? (val >> 16) : (val >> 20);
+ return val & 0xf;
+}
+
+/**
+ * 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);
+}
+
+static const struct of_device_id ve_spc_ids[] __initconst = {
+ { .compatible = "arm,vexpress-spc,v2p-ca15_a7" },
+ { .compatible = "arm,vexpress-spc" },
+ {},
+};
+
+static int __init ve_spc_probe(void)
+{
+ int ret;
+ struct device_node *node = of_find_matching_node(NULL, ve_spc_ids);
+
+ if (!node)
+ return -ENODEV;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ pr_err(SPCLOG "unable to allocate mem\n");
+ return -ENOMEM;
+ }
+
+ info->baseaddr = of_iomap(node, 0);
+ if (!info->baseaddr) {
+ pr_err(SPCLOG "unable to ioremap memory\n");
+ ret = -ENXIO;
+ goto mem_free;
+ }
+
+ info->a15_clusid = readl_relaxed(info->baseaddr + A15_CONF) & 0xf;
+
+ /*
+ * 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);
+ pr_info("vexpress-spc loaded at %p\n", info->baseaddr);
+ return 0;
+
+mem_free:
+ kfree(info);
+ return ret;
+}
+
+/**
+ * ve_spc_init()
+ *
+ * Function exported to manage pre early_initcall initialization.
+ * SPC code is needed very early in the boot process to bring CPUs out of
+ * reset and initialize power management back-end so an init interface is
+ * provided to platform code to allow early initialization. The init
+ * interface can be removed as soon as the DT layer and platform bus allow
+ * platform device creation and probing before SMP boot.
+ */
+int __init ve_spc_init(void)
+{
+ static int ve_spc_init_status __initdata = -EAGAIN;
+
+ if (ve_spc_init_status == -EAGAIN)
+ ve_spc_init_status = ve_spc_probe();
+
+ return ve_spc_init_status;
+}
+early_initcall(ve_spc_init);
@@ -124,4 +124,21 @@ void vexpress_osc_of_setup(struct device_node *node);
void vexpress_clk_init(void __iomem *sp810_base);
void vexpress_clk_of_init(void);
+/* SPC */
+
+#ifdef CONFIG_VEXPRESS_SPC
+int __init ve_spc_init(void);
+void ve_spc_global_wakeup_irq(bool set);
+void ve_spc_cpu_wakeup_irq(u32 cluster, u32 cpu, bool set);
+void ve_spc_set_resume_addr(u32 cluster, u32 cpu, u32 addr);
+u32 ve_spc_get_nr_cpus(u32 cluster);
+void ve_spc_powerdown(u32 cluster, bool enable);
+#else
+static inline int ve_spc_init(void) { return -ENODEV; }
+static inline void ve_spc_global_wakeup_irq(bool set) { }
+static inline void ve_spc_cpu_wakeup_irq(u32 cluster, u32 cpu, bool set) { }
+static inline void ve_spc_set_resume_addr(u32 cluster, u32 cpu, u32 addr) { }
+static inline u32 ve_spc_get_nr_cpus(u32 cluster) { return 0; }
+static inline void ve_spc_powerdown(u32 cluster, bool enable) { }
+#endif
#endif