https://github.com/torvalds/linux
Tip revision: df0cc57e057f18e44dac8e6c18aba47ab53202f9 authored by Linus Torvalds on 09 January 2022, 22:55:34 UTC
Linux 5.16
Linux 5.16
Tip revision: df0cc57
mc_smp.c
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2018 Chen-Yu Tsai
*
* Chen-Yu Tsai <wens@csie.org>
*
* arch/arm/mach-sunxi/mc_smp.c
*
* Based on Allwinner code, arch/arm/mach-exynos/mcpm-exynos.c, and
* arch/arm/mach-hisi/platmcpm.c
* Cluster cache enable trampoline code adapted from MCPM framework
*/
#include <linux/arm-cci.h>
#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>
#include <linux/smp.h>
#include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <asm/cputype.h>
#include <asm/idmap.h>
#include <asm/smp_plat.h>
#include <asm/suspend.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_A7 BIT(4)
#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))
#define CPUCFG_CX_RST_CTRL_ETM_RST_ALL (0xf << 20)
#define CPUCFG_CX_RST_CTRL_DBG_RST(n) BIT(16 + (n))
#define CPUCFG_CX_RST_CTRL_DBG_RST_ALL (0xf << 16)
#define CPUCFG_CX_RST_CTRL_H_RST BIT(12)
#define CPUCFG_CX_RST_CTRL_L2_RST BIT(8)
#define CPUCFG_CX_RST_CTRL_CX_RST(n) BIT(4 + (n))
#define CPUCFG_CX_RST_CTRL_CORE_RST(n) BIT(n)
#define CPUCFG_CX_RST_CTRL_CORE_RST_ALL (0xf << 0)
#define PRCM_CPU_PO_RST_CTRL(c) (0x4 + 0x4 * (c))
#define PRCM_CPU_PO_RST_CTRL_CORE(n) BIT(n)
#define PRCM_CPU_PO_RST_CTRL_CORE_ALL 0xf
#define PRCM_PWROFF_GATING_REG(c) (0x100 + 0x4 * (c))
/* The power off register for clusters are different from a80 and a83t */
#define PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I BIT(0)
#define PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I BIT(4)
#define PRCM_PWROFF_GATING_REG_CORE(n) BIT(n)
#define PRCM_PWR_SWITCH_REG(c, cpu) (0x140 + 0x10 * (c) + 0x4 * (cpu))
#define PRCM_CPU_SOFT_ENTRY_REG 0x164
/* R_CPUCFG registers, specific to sun8i-a83t */
#define R_CPUCFG_CLUSTER_PO_RST_CTRL(c) (0x30 + (c) * 0x4)
#define R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(n) BIT(n)
#define R_CPUCFG_CPU_SOFT_ENTRY_REG 0x01a4
#define CPU0_SUPPORT_HOTPLUG_MAGIC0 0xFA50392F
#define CPU0_SUPPORT_HOTPLUG_MAGIC1 0x790DCA3A
static void __iomem *cpucfg_base;
static void __iomem *prcm_base;
static void __iomem *sram_b_smp_base;
static void __iomem *r_cpucfg_base;
extern void sunxi_mc_smp_secondary_startup(void);
extern void sunxi_mc_smp_resume(void);
static bool is_a83t;
static bool sunxi_core_is_cortex_a15(unsigned int core, unsigned int cluster)
{
struct device_node *node;
int cpu = cluster * SUNXI_CPUS_PER_CLUSTER + core;
bool is_compatible;
node = of_cpu_device_node_get(cpu);
/* In case of_cpu_device_node_get fails */
if (!node)
node = of_get_cpu_node(cpu, NULL);
if (!node) {
/*
* There's no point in returning an error, since we
* would be mid way in a core or cluster power sequence.
*/
pr_err("%s: Couldn't get CPU cluster %u core %u device node\n",
__func__, cluster, core);
return false;
}
is_compatible = of_device_is_compatible(node, "arm,cortex-a15");
of_node_put(node);
return is_compatible;
}
static int sunxi_cpu_power_switch_set(unsigned int cpu, unsigned int cluster,
bool enable)
{
u32 reg;
/* control sequence from Allwinner A80 user manual v1.2 PRCM section */
reg = readl(prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
if (enable) {
if (reg == 0x00) {
pr_debug("power clamp for cluster %u cpu %u already open\n",
cluster, cpu);
return 0;
}
writel(0xff, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
udelay(10);
writel(0xfe, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
udelay(10);
writel(0xf8, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
udelay(10);
writel(0xf0, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
udelay(10);
writel(0x00, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
udelay(10);
} else {
writel(0xff, prcm_base + PRCM_PWR_SWITCH_REG(cluster, cpu));
udelay(10);
}
return 0;
}
static void sunxi_cpu0_hotplug_support_set(bool enable)
{
if (enable) {
writel(CPU0_SUPPORT_HOTPLUG_MAGIC0, sram_b_smp_base);
writel(CPU0_SUPPORT_HOTPLUG_MAGIC1, sram_b_smp_base + 0x4);
} else {
writel(0x0, sram_b_smp_base);
writel(0x0, sram_b_smp_base + 0x4);
}
}
static int sunxi_cpu_powerup(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;
/* Set hotplug support magic flags for cpu0 */
if (cluster == 0 && cpu == 0)
sunxi_cpu0_hotplug_support_set(true);
/* assert processor power-on reset */
reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
reg &= ~PRCM_CPU_PO_RST_CTRL_CORE(cpu);
writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
if (is_a83t) {
/* assert cpu power-on reset */
reg = readl(r_cpucfg_base +
R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
reg &= ~(R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(cpu));
writel(reg, r_cpucfg_base +
R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
udelay(10);
}
/* Cortex-A7: hold L1 reset disable signal low */
if (!sunxi_core_is_cortex_a15(cpu, cluster)) {
reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster));
reg &= ~CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE(cpu);
writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster));
}
/* assert processor related resets */
reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
reg &= ~CPUCFG_CX_RST_CTRL_DBG_RST(cpu);
/*
* Allwinner code also asserts resets for NEON on A15. According
* to ARM manuals, asserting power-on reset is sufficient.
*/
if (!sunxi_core_is_cortex_a15(cpu, cluster))
reg &= ~CPUCFG_CX_RST_CTRL_ETM_RST(cpu);
writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
/* open power switch */
sunxi_cpu_power_switch_set(cpu, cluster, true);
/* Handle A83T bit swap */
if (is_a83t) {
if (cpu == 0)
cpu = 4;
}
/* clear processor power gate */
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);
/* Handle A83T bit swap */
if (is_a83t) {
if (cpu == 4)
cpu = 0;
}
/* de-assert processor power-on reset */
reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
reg |= PRCM_CPU_PO_RST_CTRL_CORE(cpu);
writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
if (is_a83t) {
reg = readl(r_cpucfg_base +
R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
reg |= R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(cpu);
writel(reg, r_cpucfg_base +
R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
udelay(10);
}
/* de-assert all processor resets */
reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
reg |= CPUCFG_CX_RST_CTRL_DBG_RST(cpu);
reg |= CPUCFG_CX_RST_CTRL_CORE_RST(cpu);
if (!sunxi_core_is_cortex_a15(cpu, cluster))
reg |= CPUCFG_CX_RST_CTRL_ETM_RST(cpu);
else
reg |= CPUCFG_CX_RST_CTRL_CX_RST(cpu); /* NEON */
writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
return 0;
}
static int sunxi_cluster_powerup(unsigned int cluster)
{
u32 reg;
pr_debug("%s: cluster %u\n", __func__, cluster);
if (cluster >= SUNXI_NR_CLUSTERS)
return -EINVAL;
/* For A83T, assert cluster cores resets */
if (is_a83t) {
reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
reg &= ~CPUCFG_CX_RST_CTRL_CORE_RST_ALL; /* Core Reset */
writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
udelay(10);
}
/* 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));
/* assert cluster processor power-on resets */
reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
reg &= ~PRCM_CPU_PO_RST_CTRL_CORE_ALL;
writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
/* assert cluster cores resets */
if (is_a83t) {
reg = readl(r_cpucfg_base +
R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
reg &= ~CPUCFG_CX_RST_CTRL_CORE_RST_ALL;
writel(reg, r_cpucfg_base +
R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
udelay(10);
}
/* assert cluster resets */
reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
reg &= ~CPUCFG_CX_RST_CTRL_DBG_SOC_RST;
reg &= ~CPUCFG_CX_RST_CTRL_DBG_RST_ALL;
reg &= ~CPUCFG_CX_RST_CTRL_H_RST;
reg &= ~CPUCFG_CX_RST_CTRL_L2_RST;
/*
* Allwinner code also asserts resets for NEON on A15. According
* to ARM manuals, asserting power-on reset is sufficient.
*/
if (!sunxi_core_is_cortex_a15(0, cluster))
reg &= ~CPUCFG_CX_RST_CTRL_ETM_RST_ALL;
writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
/* hold L1/L2 reset disable signals low */
reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster));
if (sunxi_core_is_cortex_a15(0, cluster)) {
/* Cortex-A15: hold L2RSTDISABLE low */
reg &= ~CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A15;
} else {
/* Cortex-A7: hold L1RSTDISABLE and L2RSTDISABLE low */
reg &= ~CPUCFG_CX_CTRL_REG0_L1_RST_DISABLE_ALL;
reg &= ~CPUCFG_CX_CTRL_REG0_L2_RST_DISABLE_A7;
}
writel(reg, cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster));
/* clear cluster power gate */
reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
if (is_a83t)
reg &= ~PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I;
else
reg &= ~PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I;
writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster));
udelay(20);
/* de-assert cluster resets */
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));
/* de-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));
return 0;
}
/*
* This bit is shared between the initial nocache_trampoline call to
* enable CCI-400 and proper cluster cache disable before power down.
*/
static void sunxi_cluster_cache_disable_without_axi(void)
{
if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
/*
* On the Cortex-A15 we need to disable
* L2 prefetching before flushing the cache.
*/
asm volatile(
"mcr p15, 1, %0, c15, c0, 3\n"
"isb\n"
"dsb"
: : "r" (0x400));
}
/* Flush all cache levels for this cluster. */
v7_exit_coherency_flush(all);
/*
* Disable cluster-level coherency by masking
* incoming snoops and DVM messages:
*/
cci_disable_port_by_cpu(read_cpuid_mpidr());
}
static int sunxi_mc_smp_cpu_table[SUNXI_NR_CLUSTERS][SUNXI_CPUS_PER_CLUSTER];
int sunxi_mc_smp_first_comer;
static DEFINE_SPINLOCK(boot_lock);
static bool sunxi_mc_smp_cluster_is_down(unsigned int cluster)
{
int i;
for (i = 0; i < SUNXI_CPUS_PER_CLUSTER; i++)
if (sunxi_mc_smp_cpu_table[cluster][i])
return false;
return true;
}
static void sunxi_mc_smp_secondary_init(unsigned int cpu)
{
/* Clear hotplug support magic flags for cpu0 */
if (cpu == 0)
sunxi_cpu0_hotplug_support_set(false);
}
static int sunxi_mc_smp_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
{
unsigned int mpidr, cpu, cluster;
mpidr = cpu_logical_map(l_cpu);
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
if (!cpucfg_base)
return -ENODEV;
if (cluster >= SUNXI_NR_CLUSTERS || cpu >= SUNXI_CPUS_PER_CLUSTER)
return -EINVAL;
spin_lock_irq(&boot_lock);
if (sunxi_mc_smp_cpu_table[cluster][cpu])
goto out;
if (sunxi_mc_smp_cluster_is_down(cluster)) {
sunxi_mc_smp_first_comer = true;
sunxi_cluster_powerup(cluster);
} else {
sunxi_mc_smp_first_comer = false;
}
/* This is read by incoming CPUs with their cache and MMU disabled */
sync_cache_w(&sunxi_mc_smp_first_comer);
sunxi_cpu_powerup(cpu, cluster);
out:
sunxi_mc_smp_cpu_table[cluster][cpu]++;
spin_unlock_irq(&boot_lock);
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;
int gating_bit = cpu;
pr_debug("%s: cluster %u cpu %u\n", __func__, cluster, cpu);
if (cpu >= SUNXI_CPUS_PER_CLUSTER || cluster >= SUNXI_NR_CLUSTERS)
return -EINVAL;
if (is_a83t && cpu == 0)
gating_bit = 4;
/* gate processor power */
reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
reg |= PRCM_PWROFF_GATING_REG_CORE(gating_bit);
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));
if (is_a83t)
reg |= PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I;
else
reg |= PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I;
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;
}
static bool sunxi_mc_smp_cpu_can_disable(unsigned int cpu)
{
/* CPU0 hotplug not handled for sun8i-a83t */
if (is_a83t)
if (cpu == 0)
return false;
return true;
}
#endif
static const struct smp_operations sunxi_mc_smp_smp_ops __initconst = {
.smp_secondary_init = sunxi_mc_smp_secondary_init,
.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,
.cpu_can_disable = sunxi_mc_smp_cpu_can_disable,
#endif
};
static bool __init sunxi_mc_smp_cpu_table_init(void)
{
unsigned int mpidr, cpu, cluster;
mpidr = read_cpuid_mpidr();
cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
if (cluster >= SUNXI_NR_CLUSTERS || cpu >= SUNXI_CPUS_PER_CLUSTER) {
pr_err("%s: boot CPU is out of bounds!\n", __func__);
return false;
}
sunxi_mc_smp_cpu_table[cluster][cpu] = 1;
return true;
}
/*
* Adapted from arch/arm/common/mc_smp_entry.c
*
* We need the trampoline code to enable CCI-400 on the first cluster
*/
typedef typeof(cpu_reset) phys_reset_t;
static int __init nocache_trampoline(unsigned long __unused)
{
phys_reset_t phys_reset;
setup_mm_for_reboot();
sunxi_cluster_cache_disable_without_axi();
phys_reset = (phys_reset_t)(unsigned long)__pa_symbol(cpu_reset);
phys_reset(__pa_symbol(sunxi_mc_smp_resume), false);
BUG();
}
static int __init sunxi_mc_smp_loopback(void)
{
int ret;
/*
* We're going to soft-restart the current CPU through the
* low-level MCPM code by leveraging the suspend/resume
* infrastructure. Let's play it safe by using cpu_pm_enter()
* in case the CPU init code path resets the VFP or similar.
*/
sunxi_mc_smp_first_comer = true;
local_irq_disable();
local_fiq_disable();
ret = cpu_pm_enter();
if (!ret) {
ret = cpu_suspend(0, nocache_trampoline);
cpu_pm_exit();
}
local_fiq_enable();
local_irq_enable();
sunxi_mc_smp_first_comer = false;
return ret;
}
/*
* This holds any device nodes that we requested resources for,
* so that we may easily release resources in the error path.
*/
struct sunxi_mc_smp_nodes {
struct device_node *prcm_node;
struct device_node *cpucfg_node;
struct device_node *sram_node;
struct device_node *r_cpucfg_node;
};
/* This structure holds SoC-specific bits tied to an enable-method string. */
struct sunxi_mc_smp_data {
const char *enable_method;
int (*get_smp_nodes)(struct sunxi_mc_smp_nodes *nodes);
bool is_a83t;
};
static void __init sunxi_mc_smp_put_nodes(struct sunxi_mc_smp_nodes *nodes)
{
of_node_put(nodes->prcm_node);
of_node_put(nodes->cpucfg_node);
of_node_put(nodes->sram_node);
of_node_put(nodes->r_cpucfg_node);
memset(nodes, 0, sizeof(*nodes));
}
static int __init sun9i_a80_get_smp_nodes(struct sunxi_mc_smp_nodes *nodes)
{
nodes->prcm_node = of_find_compatible_node(NULL, NULL,
"allwinner,sun9i-a80-prcm");
if (!nodes->prcm_node) {
pr_err("%s: PRCM not available\n", __func__);
return -ENODEV;
}
nodes->cpucfg_node = of_find_compatible_node(NULL, NULL,
"allwinner,sun9i-a80-cpucfg");
if (!nodes->cpucfg_node) {
pr_err("%s: CPUCFG not available\n", __func__);
return -ENODEV;
}
nodes->sram_node = of_find_compatible_node(NULL, NULL,
"allwinner,sun9i-a80-smp-sram");
if (!nodes->sram_node) {
pr_err("%s: Secure SRAM not available\n", __func__);
return -ENODEV;
}
return 0;
}
static int __init sun8i_a83t_get_smp_nodes(struct sunxi_mc_smp_nodes *nodes)
{
nodes->prcm_node = of_find_compatible_node(NULL, NULL,
"allwinner,sun8i-a83t-r-ccu");
if (!nodes->prcm_node) {
pr_err("%s: PRCM not available\n", __func__);
return -ENODEV;
}
nodes->cpucfg_node = of_find_compatible_node(NULL, NULL,
"allwinner,sun8i-a83t-cpucfg");
if (!nodes->cpucfg_node) {
pr_err("%s: CPUCFG not available\n", __func__);
return -ENODEV;
}
nodes->r_cpucfg_node = of_find_compatible_node(NULL, NULL,
"allwinner,sun8i-a83t-r-cpucfg");
if (!nodes->r_cpucfg_node) {
pr_err("%s: RCPUCFG not available\n", __func__);
return -ENODEV;
}
return 0;
}
static const struct sunxi_mc_smp_data sunxi_mc_smp_data[] __initconst = {
{
.enable_method = "allwinner,sun9i-a80-smp",
.get_smp_nodes = sun9i_a80_get_smp_nodes,
},
{
.enable_method = "allwinner,sun8i-a83t-smp",
.get_smp_nodes = sun8i_a83t_get_smp_nodes,
.is_a83t = true,
},
};
static int __init sunxi_mc_smp_init(void)
{
struct sunxi_mc_smp_nodes nodes = { 0 };
struct device_node *node;
struct resource res;
void __iomem *addr;
int i, ret;
/*
* Don't bother checking the "cpus" node, as an enable-method
* property in that node is undocumented.
*/
node = of_cpu_device_node_get(0);
if (!node)
return -ENODEV;
/*
* We can't actually use the enable-method magic in the kernel.
* Our loopback / trampoline code uses the CPU suspend framework,
* which requires the identity mapping be available. It would not
* yet be available if we used the .init_cpus or .prepare_cpus
* callbacks in smp_operations, which we would use if we were to
* use CPU_METHOD_OF_DECLARE
*/
for (i = 0; i < ARRAY_SIZE(sunxi_mc_smp_data); i++) {
ret = of_property_match_string(node, "enable-method",
sunxi_mc_smp_data[i].enable_method);
if (!ret)
break;
}
is_a83t = sunxi_mc_smp_data[i].is_a83t;
of_node_put(node);
if (ret)
return -ENODEV;
if (!sunxi_mc_smp_cpu_table_init())
return -EINVAL;
if (!cci_probed()) {
pr_err("%s: CCI-400 not available\n", __func__);
return -ENODEV;
}
/* Get needed device tree nodes */
ret = sunxi_mc_smp_data[i].get_smp_nodes(&nodes);
if (ret)
goto err_put_nodes;
/*
* Unfortunately we can not request the I/O region for the PRCM.
* It is shared with the PRCM clock.
*/
prcm_base = of_iomap(nodes.prcm_node, 0);
if (!prcm_base) {
pr_err("%s: failed to map PRCM registers\n", __func__);
ret = -ENOMEM;
goto err_put_nodes;
}
cpucfg_base = of_io_request_and_map(nodes.cpucfg_node, 0,
"sunxi-mc-smp");
if (IS_ERR(cpucfg_base)) {
ret = PTR_ERR(cpucfg_base);
pr_err("%s: failed to map CPUCFG registers: %d\n",
__func__, ret);
goto err_unmap_prcm;
}
if (is_a83t) {
r_cpucfg_base = of_io_request_and_map(nodes.r_cpucfg_node,
0, "sunxi-mc-smp");
if (IS_ERR(r_cpucfg_base)) {
ret = PTR_ERR(r_cpucfg_base);
pr_err("%s: failed to map R-CPUCFG registers\n",
__func__);
goto err_unmap_release_cpucfg;
}
} else {
sram_b_smp_base = of_io_request_and_map(nodes.sram_node, 0,
"sunxi-mc-smp");
if (IS_ERR(sram_b_smp_base)) {
ret = PTR_ERR(sram_b_smp_base);
pr_err("%s: failed to map secure SRAM\n", __func__);
goto err_unmap_release_cpucfg;
}
}
/* Configure CCI-400 for boot cluster */
ret = sunxi_mc_smp_loopback();
if (ret) {
pr_err("%s: failed to configure boot cluster: %d\n",
__func__, ret);
goto err_unmap_release_sram_rcpucfg;
}
/* We don't need the device nodes anymore */
sunxi_mc_smp_put_nodes(&nodes);
/* Set the hardware entry point address */
if (is_a83t)
addr = r_cpucfg_base + R_CPUCFG_CPU_SOFT_ENTRY_REG;
else
addr = prcm_base + PRCM_CPU_SOFT_ENTRY_REG;
writel(__pa_symbol(sunxi_mc_smp_secondary_startup), addr);
/* Actually enable multi cluster SMP */
smp_set_ops(&sunxi_mc_smp_smp_ops);
pr_info("sunxi multi cluster SMP support installed\n");
return 0;
err_unmap_release_sram_rcpucfg:
if (is_a83t) {
iounmap(r_cpucfg_base);
of_address_to_resource(nodes.r_cpucfg_node, 0, &res);
} else {
iounmap(sram_b_smp_base);
of_address_to_resource(nodes.sram_node, 0, &res);
}
release_mem_region(res.start, resource_size(&res));
err_unmap_release_cpucfg:
iounmap(cpucfg_base);
of_address_to_resource(nodes.cpucfg_node, 0, &res);
release_mem_region(res.start, resource_size(&res));
err_unmap_prcm:
iounmap(prcm_base);
err_put_nodes:
sunxi_mc_smp_put_nodes(&nodes);
return ret;
}
early_initcall(sunxi_mc_smp_init);