* GNU General Public License for more details.
*/
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
#include <linux/err.h>
+#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/pm_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
#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;
/*
* 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;
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 = dev_pm_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");
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
return 0;
}
+
+struct clk_spc {
+ struct clk_hw hw;
+ int cluster;
+};
+
+#define to_clk_spc(spc) container_of(spc, struct clk_spc, hw)
+static unsigned long spc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_spc *spc = to_clk_spc(hw);
+ u32 freq;
+
+ if (ve_spc_get_performance(spc->cluster, &freq))
+ return -EIO;
+
+ return freq * 1000;
+}
+
+static long spc_round_rate(struct clk_hw *hw, unsigned long drate,
+ unsigned long *parent_rate)
+{
+ struct clk_spc *spc = to_clk_spc(hw);
+
+ return ve_spc_round_performance(spc->cluster, drate);
+}
+
+static int spc_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_spc *spc = to_clk_spc(hw);
+
+ return ve_spc_set_performance(spc->cluster, rate / 1000);
+}
+
+static struct clk_ops clk_spc_ops = {
+ .recalc_rate = spc_recalc_rate,
+ .round_rate = spc_round_rate,
+ .set_rate = spc_set_rate,
+};
+
+static struct clk *ve_spc_clk_register(struct device *cpu_dev)
+{
+ struct clk_init_data init;
+ struct clk_spc *spc;
+
+ spc = kzalloc(sizeof(*spc), GFP_KERNEL);
+ if (!spc) {
+ pr_err("could not allocate spc clk\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ spc->hw.init = &init;
+ spc->cluster = topology_physical_package_id(cpu_dev->id);
+
+ init.name = dev_name(cpu_dev);
+ init.ops = &clk_spc_ops;
+ init.flags = CLK_IS_ROOT | CLK_GET_RATE_NOCACHE;
+ init.num_parents = 0;
+
+ return devm_clk_register(cpu_dev, &spc->hw);
+}
+
+static int __init ve_spc_clk_init(void)
+{
+ int cpu;
+ struct clk *clk;
+
+ if (!info)
+ return 0; /* Continue only if SPC is initialised */
+
+ if (ve_spc_populate_opps(0) || ve_spc_populate_opps(1)) {
+ pr_err("failed to build OPP table\n");
+ return -ENODEV;
+ }
+
+ for_each_possible_cpu(cpu) {
+ struct device *cpu_dev = get_cpu_device(cpu);
+ if (!cpu_dev) {
+ pr_warn("failed to get cpu%d device\n", cpu);
+ continue;
+ }
+ clk = ve_spc_clk_register(cpu_dev);
+ if (IS_ERR(clk)) {
+ pr_warn("failed to register cpu%d clock\n", cpu);
+ continue;
+ }
+ if (clk_register_clkdev(clk, NULL, dev_name(cpu_dev))) {
+ pr_warn("failed to register cpu%d clock lookup\n", cpu);
+ continue;
+ }
+
+ if (ve_init_opp_table(cpu_dev))
+ pr_warn("failed to initialise cpu%d opp table\n", cpu);
+ }
+
+ platform_device_register_simple("vexpress-spc-cpufreq", -1, NULL, 0);
+ return 0;
+}
+module_init(ve_spc_clk_init);
projects / linux-drm-fsl-dcu.git / blobdiff