@@ -66,10 +66,22 @@ config ARCH_VEXPRESS_DCSCB
This is needed to provide CPU and cluster power management
on RTSM implementing big.LITTLE.
+config ARCH_VEXPRESS_SPC
+ bool "Versatile Express Serial Power Controller (SPC)"
+ select ARCH_HAS_CPUFREQ
+ select ARCH_HAS_OPP
+ select PM_OPP
+ help
+ The TC2 (A15x2 A7x3) versatile express core tile integrates a logic
+ block called Serial Power Controller (SPC) that provides the interface
+ between the dual cluster test-chip and the M3 microcontroller that
+ carries out power management.
+
config ARCH_VEXPRESS_TC2_PM
bool "Versatile Express TC2 power management"
depends on MCPM
select ARM_CCI
+ select ARCH_VEXPRESS_SPC
help
Support for CPU and cluster power management on Versatile Express
with a TC2 (A15x2 A7x3) big.LITTLE core tile.
@@ -8,7 +8,8 @@ obj-y := v2m.o
obj-$(CONFIG_ARCH_VEXPRESS_CA9X4) += ct-ca9x4.o
obj-$(CONFIG_ARCH_VEXPRESS_DCSCB) += dcscb.o dcscb_setup.o
CFLAGS_dcscb.o += -march=armv7-a
-obj-$(CONFIG_ARCH_VEXPRESS_TC2_PM) += tc2_pm.o spc.o
+obj-$(CONFIG_ARCH_VEXPRESS_SPC) += spc.o
+obj-$(CONFIG_ARCH_VEXPRESS_TC2_PM) += tc2_pm.o
CFLAGS_tc2_pm.o += -march=armv7-a
obj-$(CONFIG_SMP) += platsmp.o
obj-$(CONFIG_HOTPLUG_CPU) += hotplug.o
@@ -17,14 +17,27 @@
* GNU General Public License for more details.
*/
+#include <linux/delay.h>
#include <linux/err.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/opp.h>
#include <linux/slab.h>
+#include <linux/semaphore.h>
#include <asm/cacheflush.h>
#define SPCLOG "vexpress-spc: "
+#define PERF_LVL_A15 0x00
+#define PERF_REQ_A15 0x04
+#define PERF_LVL_A7 0x08
+#define PERF_REQ_A7 0x0c
+#define COMMS 0x10
+#define COMMS_REQ 0x14
+#define PWC_STATUS 0x18
+#define PWC_FLAG 0x1c
+
/* SPC wake-up IRQs status and mask */
#define WAKE_INT_MASK 0x24
#define WAKE_INT_RAW 0x28
@@ -36,12 +49,45 @@
#define A15_BX_ADDR0 0x68
#define A7_BX_ADDR0 0x78
+/* SPC system config interface registers */
+#define SYSCFG_WDATA 0x70
+#define SYSCFG_RDATA 0x74
+
+/* A15/A7 OPP virtual register base */
+#define A15_PERFVAL_BASE 0xC10
+#define A7_PERFVAL_BASE 0xC30
+
+/* Config interface control bits */
+#define SYSCFG_START (1 << 31)
+#define SYSCFG_SCC (6 << 20)
+#define SYSCFG_STAT (14 << 20)
+
/* wake-up interrupt masks */
#define GBL_WAKEUP_INT_MSK (0x3 << 10)
/* TC2 static dual-cluster configuration */
#define MAX_CLUSTERS 2
+/*
+ * Even though the SPC takes max 3-5 ms to complete any OPP/COMMS
+ * operation, the operation could start just before jiffie is about
+ * to be incremented. So setting timeout value of 20ms = 2jiffies@100Hz
+ */
+#define TIMEOUT_US 20000
+
+#define MAX_OPPS 8
+#define CA15_DVFS 0
+#define CA7_DVFS 1
+#define SPC_SYS_CFG 2
+#define STAT_COMPLETE(type) ((1 << 0) << (type << 2))
+#define STAT_ERR(type) ((1 << 1) << (type << 2))
+#define RESPONSE_MASK(type) (STAT_COMPLETE(type) | STAT_ERR(type))
+
+struct ve_spc_opp {
+ unsigned long freq;
+ unsigned long u_volt;
+};
+
struct ve_spc_drvdata {
void __iomem *baseaddr;
/*
@@ -49,6 +95,12 @@ struct ve_spc_drvdata {
* It corresponds to A15 processors MPIDR[15:8] bitfield
*/
u32 a15_clusid;
+ uint32_t cur_rsp_mask;
+ uint32_t cur_rsp_stat;
+ struct semaphore sem;
+ struct completion done;
+ struct ve_spc_opp *opps[MAX_CLUSTERS];
+ int num_opps[MAX_CLUSTERS];
};
static struct ve_spc_drvdata *info;
@@ -157,8 +209,197 @@ void ve_spc_powerdown(u32 cluster, bool enable)
writel_relaxed(enable, info->baseaddr + pwdrn_reg);
}
-int __init ve_spc_init(void __iomem *baseaddr, u32 a15_clusid)
+static int ve_spc_get_performance(int cluster, u32 *freq)
+{
+ struct ve_spc_opp *opps = info->opps[cluster];
+ u32 perf_cfg_reg = 0;
+ u32 perf;
+
+ perf_cfg_reg = cluster_is_a15(cluster) ? PERF_LVL_A15 : PERF_LVL_A7;
+
+ perf = readl_relaxed(info->baseaddr + perf_cfg_reg);
+ if (perf >= info->num_opps[cluster])
+ return -EINVAL;
+
+ opps += perf;
+ *freq = opps->freq;
+
+ return 0;
+}
+
+/* find closest match to given frequency in OPP table */
+static int ve_spc_round_performance(int cluster, u32 freq)
+{
+ int idx, max_opp = info->num_opps[cluster];
+ struct ve_spc_opp *opps = info->opps[cluster];
+ u32 fmin = 0, fmax = ~0, ftmp;
+
+ freq /= 1000; /* OPP entries in kHz */
+ for (idx = 0; idx < max_opp; idx++, opps++) {
+ ftmp = opps->freq;
+ if (ftmp >= freq) {
+ if (ftmp <= fmax)
+ fmax = ftmp;
+ } else {
+ if (ftmp >= fmin)
+ fmin = ftmp;
+ }
+ }
+ if (fmax != ~0)
+ return fmax * 1000;
+ else
+ return fmin * 1000;
+}
+
+static int ve_spc_find_performance_index(int cluster, u32 freq)
+{
+ int idx, max_opp = info->num_opps[cluster];
+ struct ve_spc_opp *opps = info->opps[cluster];
+
+ for (idx = 0; idx < max_opp; idx++, opps++)
+ if (opps->freq == freq)
+ break;
+ return (idx == max_opp) ? -EINVAL : idx;
+}
+
+static int ve_spc_waitforcompletion(int req_type)
+{
+ int ret = wait_for_completion_interruptible_timeout(
+ &info->done, usecs_to_jiffies(TIMEOUT_US));
+ if (ret == 0)
+ ret = -ETIMEDOUT;
+ else if (ret > 0)
+ ret = info->cur_rsp_stat & STAT_COMPLETE(req_type) ? 0 : -EIO;
+ return ret;
+}
+
+static int ve_spc_set_performance(int cluster, u32 freq)
+{
+ u32 perf_cfg_reg, perf_stat_reg;
+ int ret, perf, req_type;
+
+ if (cluster_is_a15(cluster)) {
+ req_type = CA15_DVFS;
+ perf_cfg_reg = PERF_LVL_A15;
+ perf_stat_reg = PERF_REQ_A15;
+ } else {
+ req_type = CA7_DVFS;
+ perf_cfg_reg = PERF_LVL_A7;
+ perf_stat_reg = PERF_REQ_A7;
+ }
+
+ perf = ve_spc_find_performance_index(cluster, freq);
+
+ if (perf < 0)
+ return perf;
+
+ if (down_timeout(&info->sem, usecs_to_jiffies(TIMEOUT_US)))
+ return -ETIME;
+
+ init_completion(&info->done);
+ info->cur_rsp_mask = RESPONSE_MASK(req_type);
+
+ writel(perf, info->baseaddr + perf_cfg_reg);
+ ret = ve_spc_waitforcompletion(req_type);
+
+ info->cur_rsp_mask = 0;
+ up(&info->sem);
+
+ return ret;
+}
+
+static int ve_spc_read_sys_cfg(int func, int offset, uint32_t *data)
+{
+ int ret;
+
+ if (down_timeout(&info->sem, usecs_to_jiffies(TIMEOUT_US)))
+ return -ETIME;
+
+ init_completion(&info->done);
+ info->cur_rsp_mask = RESPONSE_MASK(SPC_SYS_CFG);
+
+ /* Set the control value */
+ writel(SYSCFG_START | func | offset >> 2, info->baseaddr + COMMS);
+ ret = ve_spc_waitforcompletion(SPC_SYS_CFG);
+
+ if (ret == 0)
+ *data = readl(info->baseaddr + SYSCFG_RDATA);
+
+ info->cur_rsp_mask = 0;
+ up(&info->sem);
+
+ return ret;
+}
+
+static irqreturn_t ve_spc_irq_handler(int irq, void *data)
+{
+ struct ve_spc_drvdata *drv_data = data;
+ uint32_t status = readl_relaxed(drv_data->baseaddr + PWC_STATUS);
+
+ if (info->cur_rsp_mask & status) {
+ info->cur_rsp_stat = status;
+ complete(&drv_data->done);
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * +--------------------------+
+ * | 31 20 | 19 0 |
+ * +--------------------------+
+ * | u_volt | freq(kHz) |
+ * +--------------------------+
+ */
+#define MULT_FACTOR 20
+#define VOLT_SHIFT 20
+#define FREQ_MASK (0xFFFFF)
+static int ve_spc_populate_opps(uint32_t cluster)
+{
+ uint32_t data = 0, off, ret, idx;
+ struct ve_spc_opp *opps;
+
+ opps = kzalloc(sizeof(*opps) * MAX_OPPS, GFP_KERNEL);
+ if (!opps)
+ return -ENOMEM;
+
+ info->opps[cluster] = opps;
+
+ off = cluster_is_a15(cluster) ? A15_PERFVAL_BASE : A7_PERFVAL_BASE;
+ for (idx = 0; idx < MAX_OPPS; idx++, off += 4, opps++) {
+ ret = ve_spc_read_sys_cfg(SYSCFG_SCC, off, &data);
+ if (!ret) {
+ opps->freq = (data & FREQ_MASK) * MULT_FACTOR;
+ opps->u_volt = data >> VOLT_SHIFT;
+ } else {
+ break;
+ }
+ }
+ info->num_opps[cluster] = idx;
+
+ return ret;
+}
+
+static int ve_init_opp_table(struct device *cpu_dev)
+{
+ int cluster = topology_physical_package_id(cpu_dev->id);
+ int idx, ret = 0, max_opp = info->num_opps[cluster];
+ struct ve_spc_opp *opps = info->opps[cluster];
+
+ for (idx = 0; idx < max_opp; idx++, opps++) {
+ ret = opp_add(cpu_dev, opps->freq * 1000, opps->u_volt);
+ if (ret) {
+ dev_warn(cpu_dev, "failed to add opp %lu %lu\n",
+ opps->freq, opps->u_volt);
+ return ret;
+ }
+ }
+ return ret;
+}
+
+int __init ve_spc_init(void __iomem *baseaddr, u32 a15_clusid, int irq)
{
+ int ret;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info) {
pr_err(SPCLOG "unable to allocate mem\n");
@@ -168,6 +409,25 @@ int __init ve_spc_init(void __iomem *baseaddr, u32 a15_clusid)
info->baseaddr = baseaddr;
info->a15_clusid = a15_clusid;
+ if (irq <= 0) {
+ pr_err(SPCLOG "Invalid IRQ %d\n", irq);
+ kfree(info);
+ return -EINVAL;
+ }
+
+ init_completion(&info->done);
+
+ readl_relaxed(info->baseaddr + PWC_STATUS);
+
+ ret = request_irq(irq, ve_spc_irq_handler, IRQF_TRIGGER_HIGH
+ | IRQF_ONESHOT, "vexpress-spc", info);
+ if (ret) {
+ pr_err(SPCLOG "IRQ %d request failed\n", irq);
+ kfree(info);
+ return -ENODEV;
+ }
+
+ sema_init(&info->sem, 1);
/*
* Multi-cluster systems may need this data when non-coherent, during
* cluster power-up/power-down. Make sure driver info reaches main
@@ -15,7 +15,7 @@
#ifndef __SPC_H_
#define __SPC_H_
-int __init ve_spc_init(void __iomem *base, u32 a15_clusid);
+int __init ve_spc_init(void __iomem *base, u32 a15_clusid, int irq);
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);
@@ -16,6 +16,7 @@
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/irqchip/arm-gic.h>
@@ -311,7 +312,7 @@ static void __naked tc2_pm_power_up_setup(unsigned int affinity_level)
static int __init tc2_pm_init(void)
{
- int ret;
+ int ret, irq;
void __iomem *scc;
u32 a15_cluster_id, a7_cluster_id, sys_info;
struct device_node *np;
@@ -336,13 +337,15 @@ static int __init tc2_pm_init(void)
tc2_nr_cpus[a15_cluster_id] = (sys_info >> 16) & 0xf;
tc2_nr_cpus[a7_cluster_id] = (sys_info >> 20) & 0xf;
+ irq = irq_of_parse_and_map(np, 0);
+
/*
* A subset of the SCC registers is also used to communicate
* with the SPC (power controller). We need to be able to
* drive it very early in the boot process to power up
* processors, so we initialize the SPC driver here.
*/
- ret = ve_spc_init(scc + SPC_BASE, a15_cluster_id);
+ ret = ve_spc_init(scc + SPC_BASE, a15_cluster_id, irq);
if (ret)
return ret;