#define pr_fmt(fmt) "mvebu-pmsu: " fmt
+#include <linux/clk.h>
#include <linux/cpu_pm.h>
+#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
+#include <linux/of_device.h>
#include <linux/io.h>
#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
#include <linux/smp.h>
#include <linux/resource.h>
+#include <linux/slab.h>
#include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <asm/smp_plat.h>
#include <asm/suspend.h>
#include <asm/tlbflush.h>
#include "common.h"
+#include "armada-370-xp.h"
static void __iomem *pmsu_mp_base;
#define PMSU_STATUS_AND_MASK_IRQ_MASK BIT(24)
#define PMSU_STATUS_AND_MASK_FIQ_MASK BIT(25)
+#define PMSU_EVENT_STATUS_AND_MASK(cpu) ((cpu * 0x100) + 0x120)
+#define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE BIT(1)
+#define PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK BIT(17)
+
#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124)
/* PMSU fabric registers */
arch_initcall(armada_370_xp_cpu_pm_init);
early_initcall(armada_370_xp_pmsu_init);
+
+static void mvebu_pmsu_dfs_request_local(void *data)
+{
+ u32 reg;
+ u32 cpu = smp_processor_id();
+ unsigned long flags;
+
+ local_irq_save(flags);
+
+ /* Prepare to enter idle */
+ reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
+ reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT |
+ PMSU_STATUS_AND_MASK_IRQ_MASK |
+ PMSU_STATUS_AND_MASK_FIQ_MASK;
+ writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
+
+ /* Request the DFS transition */
+ reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
+ reg |= PMSU_CONTROL_AND_CONFIG_DFS_REQ;
+ writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(cpu));
+
+ /* The fact of entering idle will trigger the DFS transition */
+ wfi();
+
+ /*
+ * We're back from idle, the DFS transition has completed,
+ * clear the idle wait indication.
+ */
+ reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
+ reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
+ writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(cpu));
+
+ local_irq_restore(flags);
+}
+
+int mvebu_pmsu_dfs_request(int cpu)
+{
+ unsigned long timeout;
+ int hwcpu = cpu_logical_map(cpu);
+ u32 reg;
+
+ /* Clear any previous DFS DONE event */
+ reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+ reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE;
+ writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+
+ /* Mask the DFS done interrupt, since we are going to poll */
+ reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+ reg |= PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
+ writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+
+ /* Trigger the DFS on the appropriate CPU */
+ smp_call_function_single(cpu, mvebu_pmsu_dfs_request_local,
+ NULL, false);
+
+ /* Poll until the DFS done event is generated */
+ timeout = jiffies + HZ;
+ while (time_before(jiffies, timeout)) {
+ reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+ if (reg & PMSU_EVENT_STATUS_AND_MASK_DFS_DONE)
+ break;
+ udelay(10);
+ }
+
+ if (time_after(jiffies, timeout))
+ return -ETIME;
+
+ /* Restore the DFS mask to its original state */
+ reg = readl(pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+ reg &= ~PMSU_EVENT_STATUS_AND_MASK_DFS_DONE_MASK;
+ writel(reg, pmsu_mp_base + PMSU_EVENT_STATUS_AND_MASK(hwcpu));
+
+ return 0;
+}
+
+static int __init armada_xp_pmsu_cpufreq_init(void)
+{
+ struct device_node *np;
+ struct resource res;
+ int ret, cpu;
+
+ if (!of_machine_is_compatible("marvell,armadaxp"))
+ return 0;
+
+ /*
+ * In order to have proper cpufreq handling, we need to ensure
+ * that the Device Tree description of the CPU clock includes
+ * the definition of the PMU DFS registers. If not, we do not
+ * register the clock notifier and the cpufreq driver. This
+ * piece of code is only for compatibility with old Device
+ * Trees.
+ */
+ np = of_find_compatible_node(NULL, NULL, "marvell,armada-xp-cpu-clock");
+ if (!np)
+ return 0;
+
+ ret = of_address_to_resource(np, 1, &res);
+ if (ret) {
+ pr_warn(FW_WARN "not enabling cpufreq, deprecated armada-xp-cpu-clock binding\n");
+ of_node_put(np);
+ return 0;
+ }
+
+ of_node_put(np);
+
+ /*
+ * For each CPU, this loop registers the operating points
+ * supported (which are the nominal CPU frequency and half of
+ * it), and registers the clock notifier that will take care
+ * of doing the PMSU part of a frequency transition.
+ */
+ for_each_possible_cpu(cpu) {
+ struct device *cpu_dev;
+ struct clk *clk;
+ int ret;
+
+ cpu_dev = get_cpu_device(cpu);
+ if (!cpu_dev) {
+ pr_err("Cannot get CPU %d\n", cpu);
+ continue;
+ }
+
+ clk = clk_get(cpu_dev, 0);
+ if (!clk) {
+ pr_err("Cannot get clock for CPU %d\n", cpu);
+ return -ENODEV;
+ }
+
+ /*
+ * In case of a failure of dev_pm_opp_add(), we don't
+ * bother with cleaning up the registered OPP (there's
+ * no function to do so), and simply cancel the
+ * registration of the cpufreq device.
+ */
+ ret = dev_pm_opp_add(cpu_dev, clk_get_rate(clk), 0);
+ if (ret) {
+ clk_put(clk);
+ return ret;
+ }
+
+ ret = dev_pm_opp_add(cpu_dev, clk_get_rate(clk) / 2, 0);
+ if (ret) {
+ clk_put(clk);
+ return ret;
+ }
+ }
+
+ platform_device_register_simple("cpufreq-generic", -1, NULL, 0);
+ return 0;
+}
+
+device_initcall(armada_xp_pmsu_cpufreq_init);
#include <linux/io.h>
#include <linux/of.h>
#include <linux/delay.h>
+#include <linux/mvebu-pmsu.h>
+#include <asm/smp_plat.h>
-#define SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET 0x0
-#define SYS_CTRL_CLK_DIVIDER_VALUE_OFFSET 0xC
-#define SYS_CTRL_CLK_DIVIDER_MASK 0x3F
+#define SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET 0x0
+#define SYS_CTRL_CLK_DIVIDER_CTRL_RESET_ALL 0xff
+#define SYS_CTRL_CLK_DIVIDER_CTRL_RESET_SHIFT 8
+#define SYS_CTRL_CLK_DIVIDER_CTRL2_OFFSET 0x8
+#define SYS_CTRL_CLK_DIVIDER_CTRL2_NBCLK_RATIO_SHIFT 16
+#define SYS_CTRL_CLK_DIVIDER_VALUE_OFFSET 0xC
+#define SYS_CTRL_CLK_DIVIDER_MASK 0x3F
+
+#define PMU_DFS_RATIO_SHIFT 16
+#define PMU_DFS_RATIO_MASK 0x3F
#define MAX_CPU 4
struct cpu_clk {
const char *clk_name;
const char *parent_name;
void __iomem *reg_base;
+ void __iomem *pmu_dfs;
};
static struct clk **clks;
return *parent_rate / div;
}
-static int clk_cpu_set_rate(struct clk_hw *hwclk, unsigned long rate,
- unsigned long parent_rate)
+static int clk_cpu_off_set_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long parent_rate)
+
{
struct cpu_clk *cpuclk = to_cpu_clk(hwclk);
u32 reg, div;
return 0;
}
+static int clk_cpu_on_set_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long parent_rate)
+{
+ u32 reg;
+ unsigned long fabric_div, target_div, cur_rate;
+ struct cpu_clk *cpuclk = to_cpu_clk(hwclk);
+
+ /*
+ * PMU DFS registers are not mapped, Device Tree does not
+ * describes them. We cannot change the frequency dynamically.
+ */
+ if (!cpuclk->pmu_dfs)
+ return -ENODEV;
+
+ cur_rate = __clk_get_rate(hwclk->clk);
+
+ reg = readl(cpuclk->reg_base + SYS_CTRL_CLK_DIVIDER_CTRL2_OFFSET);
+ fabric_div = (reg >> SYS_CTRL_CLK_DIVIDER_CTRL2_NBCLK_RATIO_SHIFT) &
+ SYS_CTRL_CLK_DIVIDER_MASK;
+
+ /* Frequency is going up */
+ if (rate == 2 * cur_rate)
+ target_div = fabric_div / 2;
+ /* Frequency is going down */
+ else
+ target_div = fabric_div;
+
+ if (target_div == 0)
+ target_div = 1;
+
+ reg = readl(cpuclk->pmu_dfs);
+ reg &= ~(PMU_DFS_RATIO_MASK << PMU_DFS_RATIO_SHIFT);
+ reg |= (target_div << PMU_DFS_RATIO_SHIFT);
+ writel(reg, cpuclk->pmu_dfs);
+
+ reg = readl(cpuclk->reg_base + SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET);
+ reg |= (SYS_CTRL_CLK_DIVIDER_CTRL_RESET_ALL <<
+ SYS_CTRL_CLK_DIVIDER_CTRL_RESET_SHIFT);
+ writel(reg, cpuclk->reg_base + SYS_CTRL_CLK_DIVIDER_CTRL_OFFSET);
+
+ return mvebu_pmsu_dfs_request(cpuclk->cpu);
+}
+
+static int clk_cpu_set_rate(struct clk_hw *hwclk, unsigned long rate,
+ unsigned long parent_rate)
+{
+ if (__clk_is_enabled(hwclk->clk))
+ return clk_cpu_on_set_rate(hwclk, rate, parent_rate);
+ else
+ return clk_cpu_off_set_rate(hwclk, rate, parent_rate);
+}
+
static const struct clk_ops cpu_ops = {
.recalc_rate = clk_cpu_recalc_rate,
.round_rate = clk_cpu_round_rate,
{
struct cpu_clk *cpuclk;
void __iomem *clock_complex_base = of_iomap(node, 0);
+ void __iomem *pmu_dfs_base = of_iomap(node, 1);
int ncpus = 0;
struct device_node *dn;
return;
}
+ if (pmu_dfs_base == NULL)
+ pr_warn("%s: pmu-dfs base register not set, dynamic frequency scaling not available\n",
+ __func__);
+
for_each_node_by_type(dn, "cpu")
ncpus++;
cpuclk[cpu].clk_name = clk_name;
cpuclk[cpu].cpu = cpu;
cpuclk[cpu].reg_base = clock_complex_base;
+ if (pmu_dfs_base)
+ cpuclk[cpu].pmu_dfs = pmu_dfs_base + 4 * cpu;
cpuclk[cpu].hw.init = &init;
init.name = cpuclk[cpu].clk_name;
projects / karo-tx-linux.git / commitdiff