#include <linux/cpu_pm.h>
#include <linux/delay.h>
#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/irqchip/arm-gic.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#define SUNXI_CPUS_PER_CLUSTER 4
#define SUNXI_NR_CLUSTERS 2
+#define POLL_USEC 100
+#define TIMEOUT_USEC 100000
+
#define CPUCFG_CX_CTRL_REG0(c) (0x10 * (c))
#define CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE(n) BIT(n)
#define CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE_ALL 0xf
#define CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A15 BIT(0)
#define CPUCFG_CX_CTRL_REG1(c) (0x10 * (c) + 0x4)
#define CPUCFG_CX_CTRL_REG1_ACINACTM BIT(0)
+#define CPUCFG_CX_STATUS(c) (0x30 + 0x4 * (c))
+#define CPUCFG_CX_STATUS_STANDBYWFI(n) BIT(16 + (n))
+#define CPUCFG_CX_STATUS_STANDBYWFIL2 BIT(0)
#define CPUCFG_CX_RST_CTRL(c) (0x80 + 0x4 * (c))
#define CPUCFG_CX_RST_CTRL_DBG_SOC_RST BIT(24)
#define CPUCFG_CX_RST_CTRL_ETM_RST(n) BIT(20 + (n))
{
u32 reg;
- pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+ pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu);
if (cpu >= SUNXI_CPUS_PER_CLUSTER || cluster >= SUNXI_NR_CLUSTERS)
return -EINVAL;
return 0;
}
+#ifdef CONFIG_HOTPLUG_CPU
+static void sunxi_cluster_cache_disable(void)
+{
+ unsigned int cluster = MPIDR_AFFINITY_LEVEL(read_cpuid_mpidr(), 1);
+ u32 reg;
+
+ pr_debug("%s: cluster %u\n", __func__, cluster);
+
+ sunxi_cluster_cache_disable_without_axi();
+
+ /* last man standing, assert ACINACTM */
+ reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster));
+ reg |= CPUCFG_CX_CTRL_REG1_ACINACTM;
+ writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster));
+}
+
+static void sunxi_mc_smp_cpu_die(unsigned int l_cpu)
+{
+ unsigned int mpidr, cpu, cluster;
+ bool last_man;
+
+ mpidr = cpu_logical_map(l_cpu);
+ cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+ pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu);
+
+ spin_lock(&boot_lock);
+ sunxi_mc_smp_cpu_table[cluster][cpu]--;
+ if (sunxi_mc_smp_cpu_table[cluster][cpu] == 1) {
+ /* A power_up request went ahead of us. */
+ pr_debug("%s: aborting due to a power up request\n",
+ __func__);
+ spin_unlock(&boot_lock);
+ return;
+ } else if (sunxi_mc_smp_cpu_table[cluster][cpu] > 1) {
+ pr_err("Cluster %d CPU%d boots multiple times\n",
+ cluster, cpu);
+ BUG();
+ }
+
+ last_man = sunxi_mc_smp_cluster_is_down(cluster);
+ spin_unlock(&boot_lock);
+
+ gic_cpu_if_down(0);
+ if (last_man)
+ sunxi_cluster_cache_disable();
+ else
+ v7_exit_coherency_flush(louis);
+
+ for (;;)
+ wfi();
+}
+
+static int sunxi_cpu_powerdown(unsigned int cpu, unsigned int cluster)
+{
+ u32 reg;
+
+ pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu);
+ if (cpu >= SUNXI_CPUS_PER_CLUSTER || cluster >= SUNXI_NR_CLUSTERS)
+ return -EINVAL;
+
+ /* gate processor power */
+ reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
+ reg |= PRCM_PWROFF_GATING_REG_CORE(cpu);
+ writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster));
+ udelay(20);
+
+ /* close power switch */
+ sunxi_cpu_power_switch_set(cpu, cluster, false);
+
+ return 0;
+}
+
+static int sunxi_cluster_powerdown(unsigned int cluster)
+{
+ u32 reg;
+
+ pr_debug("%s: cluster %u\n", __func__, cluster);
+ if (cluster >= SUNXI_NR_CLUSTERS)
+ return -EINVAL;
+
+ /* assert cluster resets or system will hang */
+ pr_debug("%s: assert cluster reset\n", __func__);
+ reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
+ reg &= ~CPUCFG_CX_RST_CTRL_DBG_SOC_RST;
+ reg &= ~CPUCFG_CX_RST_CTRL_H_RST;
+ reg &= ~CPUCFG_CX_RST_CTRL_L2_RST;
+ writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
+
+ /* gate cluster power */
+ pr_debug("%s: gate cluster power\n", __func__);
+ reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
+ reg |= PRCM_PWROFF_GATING_REG_CLUSTER;
+ writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster));
+ udelay(20);
+
+ return 0;
+}
+
+static int sunxi_mc_smp_cpu_kill(unsigned int l_cpu)
+{
+ unsigned int mpidr, cpu, cluster;
+ unsigned int tries, count;
+ int ret = 0;
+ u32 reg;
+
+ mpidr = cpu_logical_map(l_cpu);
+ cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+ cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+
+ /* This should never happen */
+ if (WARN_ON(cluster >= SUNXI_NR_CLUSTERS ||
+ cpu >= SUNXI_CPUS_PER_CLUSTER))
+ return 0;
+
+ /* wait for CPU core to die and enter WFI */
+ count = TIMEOUT_USEC / POLL_USEC;
+ spin_lock_irq(&boot_lock);
+ for (tries = 0; tries < count; tries++) {
+ spin_unlock_irq(&boot_lock);
+ usleep_range(POLL_USEC / 2, POLL_USEC);
+ spin_lock_irq(&boot_lock);
+
+ /*
+ * If the user turns off a bunch of cores at the same
+ * time, the kernel might call cpu_kill before some of
+ * them are ready. This is because boot_lock serializes
+ * both cpu_die and cpu_kill callbacks. Either one could
+ * run first. We should wait for cpu_die to complete.
+ */
+ if (sunxi_mc_smp_cpu_table[cluster][cpu])
+ continue;
+
+ reg = readl(cpucfg_base + CPUCFG_CX_STATUS(cluster));
+ if (reg & CPUCFG_CX_STATUS_STANDBYWFI(cpu))
+ break;
+ }
+
+ if (tries >= count) {
+ ret = ETIMEDOUT;
+ goto out;
+ }
+
+ /* power down CPU core */
+ sunxi_cpu_powerdown(cpu, cluster);
+
+ if (!sunxi_mc_smp_cluster_is_down(cluster))
+ goto out;
+
+ /* wait for cluster L2 WFI */
+ ret = readl_poll_timeout(cpucfg_base + CPUCFG_CX_STATUS(cluster), reg,
+ reg & CPUCFG_CX_STATUS_STANDBYWFIL2,
+ POLL_USEC, TIMEOUT_USEC);
+ if (ret) {
+ /*
+ * Ignore timeout on the cluster. Leaving the cluster on
+ * will not affect system execution, just use a bit more
+ * power. But returning an error here will only confuse
+ * the user as the CPU has already been shutdown.
+ */
+ ret = 0;
+ goto out;
+ }
+
+ /* Power down cluster */
+ sunxi_cluster_powerdown(cluster);
+
+out:
+ spin_unlock_irq(&boot_lock);
+ pr_debug("%s: cluster %u cpu %u powerdown: %d\n",
+ __func__, cluster, cpu, ret);
+ return !ret;
+}
+
+#endif
+
static const struct smp_operations sunxi_mc_smp_smp_ops __initconst = {
.smp_boot_secondary = sunxi_mc_smp_boot_secondary,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = sunxi_mc_smp_cpu_die,
+ .cpu_kill = sunxi_mc_smp_cpu_kill,
+#endif
};
static bool __init sunxi_mc_smp_cpu_table_init(void)
projects / linux.git / commitdiff