linux/drivers/soc/renesas/r8a779a0-sysc.c
Yoshihiro Shimoda 1b4298f000 soc: renesas: r8a779a0-sysc: Add r8a779a0 support
Add support for R-Car V3U (R8A779A0) SoC power areas and register
access, because register specification differs from R-Car Gen2/3.

Inspired by patches in the BSP by Tho Vu.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1599810232-29035-5-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2020-09-16 08:57:31 +02:00

449 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Renesas R-Car V3U System Controller
*
* Copyright (C) 2020 Renesas Electronics Corp.
*/
#include <linux/bits.h>
#include <linux/clk/renesas.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/of_address.h>
#include <linux/pm_domain.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <dt-bindings/power/r8a779a0-sysc.h>
/*
* Power Domain flags
*/
#define PD_CPU BIT(0) /* Area contains main CPU core */
#define PD_SCU BIT(1) /* Area contains SCU and L2 cache */
#define PD_NO_CR BIT(2) /* Area lacks PWR{ON,OFF}CR registers */
#define PD_CPU_NOCR PD_CPU | PD_NO_CR /* CPU area lacks CR */
#define PD_ALWAYS_ON PD_NO_CR /* Always-on area */
/*
* Description of a Power Area
*/
struct r8a779a0_sysc_area {
const char *name;
u8 pdr; /* PDRn */
int parent; /* -1 if none */
unsigned int flags; /* See PD_* */
};
/*
* SoC-specific Power Area Description
*/
struct r8a779a0_sysc_info {
const struct r8a779a0_sysc_area *areas;
unsigned int num_areas;
};
static struct r8a779a0_sysc_area r8a779a0_areas[] __initdata = {
{ "always-on", R8A779A0_PD_ALWAYS_ON, -1, PD_ALWAYS_ON },
{ "a3e0", R8A779A0_PD_A3E0, R8A779A0_PD_ALWAYS_ON, PD_SCU },
{ "a3e1", R8A779A0_PD_A3E1, R8A779A0_PD_ALWAYS_ON, PD_SCU },
{ "a2e0d0", R8A779A0_PD_A2E0D0, R8A779A0_PD_A3E0, PD_SCU },
{ "a2e0d1", R8A779A0_PD_A2E0D1, R8A779A0_PD_A3E0, PD_SCU },
{ "a2e1d0", R8A779A0_PD_A2E1D0, R8A779A0_PD_A3E1, PD_SCU },
{ "a2e1d1", R8A779A0_PD_A2E1D1, R8A779A0_PD_A3E1, PD_SCU },
{ "a1e0d0c0", R8A779A0_PD_A1E0D0C0, R8A779A0_PD_A2E0D0, PD_CPU_NOCR },
{ "a1e0d0c1", R8A779A0_PD_A1E0D0C1, R8A779A0_PD_A2E0D0, PD_CPU_NOCR },
{ "a1e0d1c0", R8A779A0_PD_A1E0D1C0, R8A779A0_PD_A2E0D1, PD_CPU_NOCR },
{ "a1e0d1c1", R8A779A0_PD_A1E0D1C1, R8A779A0_PD_A2E0D1, PD_CPU_NOCR },
{ "a1e1d0c0", R8A779A0_PD_A1E1D0C0, R8A779A0_PD_A2E1D0, PD_CPU_NOCR },
{ "a1e1d0c1", R8A779A0_PD_A1E1D0C1, R8A779A0_PD_A2E1D0, PD_CPU_NOCR },
{ "a1e1d1c0", R8A779A0_PD_A1E1D1C0, R8A779A0_PD_A2E1D1, PD_CPU_NOCR },
{ "a1e1d1c1", R8A779A0_PD_A1E1D1C1, R8A779A0_PD_A2E1D1, PD_CPU_NOCR },
{ "3dg-a", R8A779A0_PD_3DG_A, R8A779A0_PD_ALWAYS_ON },
{ "3dg-b", R8A779A0_PD_3DG_B, R8A779A0_PD_3DG_A },
{ "a3vip0", R8A779A0_PD_A3VIP0, R8A779A0_PD_ALWAYS_ON },
{ "a3vip1", R8A779A0_PD_A3VIP1, R8A779A0_PD_ALWAYS_ON },
{ "a3vip3", R8A779A0_PD_A3VIP3, R8A779A0_PD_ALWAYS_ON },
{ "a3vip2", R8A779A0_PD_A3VIP2, R8A779A0_PD_ALWAYS_ON },
{ "a3isp01", R8A779A0_PD_A3ISP01, R8A779A0_PD_ALWAYS_ON },
{ "a3isp23", R8A779A0_PD_A3ISP23, R8A779A0_PD_ALWAYS_ON },
{ "a3ir", R8A779A0_PD_A3IR, R8A779A0_PD_ALWAYS_ON },
{ "a2cn0", R8A779A0_PD_A2CN0, R8A779A0_PD_A3IR },
{ "a2imp01", R8A779A0_PD_A2IMP01, R8A779A0_PD_A3IR },
{ "a2dp0", R8A779A0_PD_A2DP0, R8A779A0_PD_A3IR },
{ "a2cv0", R8A779A0_PD_A2CV0, R8A779A0_PD_A3IR },
{ "a2cv1", R8A779A0_PD_A2CV1, R8A779A0_PD_A3IR },
{ "a2cv4", R8A779A0_PD_A2CV4, R8A779A0_PD_A3IR },
{ "a2cv6", R8A779A0_PD_A2CV6, R8A779A0_PD_A3IR },
{ "a2cn2", R8A779A0_PD_A2CN2, R8A779A0_PD_A3IR },
{ "a2imp23", R8A779A0_PD_A2IMP23, R8A779A0_PD_A3IR },
{ "a2dp1", R8A779A0_PD_A2DP0, R8A779A0_PD_A3IR },
{ "a2cv2", R8A779A0_PD_A2CV0, R8A779A0_PD_A3IR },
{ "a2cv3", R8A779A0_PD_A2CV1, R8A779A0_PD_A3IR },
{ "a2cv5", R8A779A0_PD_A2CV4, R8A779A0_PD_A3IR },
{ "a2cv7", R8A779A0_PD_A2CV6, R8A779A0_PD_A3IR },
{ "a2cn1", R8A779A0_PD_A2CN1, R8A779A0_PD_A3IR },
{ "a1cnn0", R8A779A0_PD_A1CNN0, R8A779A0_PD_A2CN0 },
{ "a1cnn2", R8A779A0_PD_A1CNN2, R8A779A0_PD_A2CN2 },
{ "a1dsp0", R8A779A0_PD_A1DSP0, R8A779A0_PD_A2CN2 },
{ "a1cnn1", R8A779A0_PD_A1CNN1, R8A779A0_PD_A2CN1 },
{ "a1dsp1", R8A779A0_PD_A1DSP1, R8A779A0_PD_A2CN1 },
};
static const struct r8a779a0_sysc_info r8a779a0_sysc_info __initconst = {
.areas = r8a779a0_areas,
.num_areas = ARRAY_SIZE(r8a779a0_areas),
};
/* SYSC Common */
#define SYSCSR 0x000 /* SYSC Status Register */
#define SYSCPONSR(x) (0x800 + ((x) * 0x4)) /* Power-ON Status Register 0 */
#define SYSCPOFFSR(x) (0x808 + ((x) * 0x4)) /* Power-OFF Status Register */
#define SYSCISCR(x) (0x810 + ((x) * 0x4)) /* Interrupt Status/Clear Register */
#define SYSCIER(x) (0x820 + ((x) * 0x4)) /* Interrupt Enable Register */
#define SYSCIMR(x) (0x830 + ((x) * 0x4)) /* Interrupt Mask Register */
/* Power Domain Registers */
#define PDRSR(n) (0x1000 + ((n) * 0x40))
#define PDRONCR(n) (0x1004 + ((n) * 0x40))
#define PDROFFCR(n) (0x1008 + ((n) * 0x40))
#define PDRESR(n) (0x100C + ((n) * 0x40))
/* PWRON/PWROFF */
#define PWRON_PWROFF BIT(0) /* Power-ON/OFF request */
/* PDRESR */
#define PDRESR_ERR BIT(0)
/* PDRSR */
#define PDRSR_OFF BIT(0) /* Power-OFF state */
#define PDRSR_ON BIT(4) /* Power-ON state */
#define PDRSR_OFF_STATE BIT(8) /* Processing Power-OFF sequence */
#define PDRSR_ON_STATE BIT(12) /* Processing Power-ON sequence */
#define SYSCSR_BUSY GENMASK(1, 0) /* All bit sets is not busy */
#define SYSCSR_TIMEOUT 10000
#define SYSCSR_DELAY_US 10
#define PDRESR_RETRIES 1000
#define PDRESR_DELAY_US 10
#define SYSCISR_TIMEOUT 10000
#define SYSCISR_DELAY_US 10
#define NUM_DOMAINS_EACH_REG BITS_PER_TYPE(u32)
static void __iomem *r8a779a0_sysc_base;
static DEFINE_SPINLOCK(r8a779a0_sysc_lock); /* SMP CPUs + I/O devices */
static int r8a779a0_sysc_pwr_on_off(u8 pdr, bool on)
{
unsigned int reg_offs;
u32 val;
int ret;
if (on)
reg_offs = PDRONCR(pdr);
else
reg_offs = PDROFFCR(pdr);
/* Wait until SYSC is ready to accept a power request */
ret = readl_poll_timeout_atomic(r8a779a0_sysc_base + SYSCSR, val,
(val & SYSCSR_BUSY) == SYSCSR_BUSY,
SYSCSR_DELAY_US, SYSCSR_TIMEOUT);
if (ret < 0)
return -EAGAIN;
/* Submit power shutoff or power resume request */
iowrite32(PWRON_PWROFF, r8a779a0_sysc_base + reg_offs);
return 0;
}
static int clear_irq_flags(unsigned int reg_idx, unsigned int isr_mask)
{
u32 val;
int ret;
iowrite32(isr_mask, r8a779a0_sysc_base + SYSCISCR(reg_idx));
ret = readl_poll_timeout_atomic(r8a779a0_sysc_base + SYSCISCR(reg_idx),
val, !(val & isr_mask),
SYSCISR_DELAY_US, SYSCISR_TIMEOUT);
if (ret < 0) {
pr_err("\n %s : Can not clear IRQ flags in SYSCISCR", __func__);
return -EIO;
}
return 0;
}
static int r8a779a0_sysc_power(u8 pdr, bool on)
{
unsigned int isr_mask;
unsigned int reg_idx, bit_idx;
unsigned int status;
unsigned long flags;
int ret = 0;
u32 val;
int k;
spin_lock_irqsave(&r8a779a0_sysc_lock, flags);
reg_idx = pdr / NUM_DOMAINS_EACH_REG;
bit_idx = pdr % NUM_DOMAINS_EACH_REG;
isr_mask = BIT(bit_idx);
/*
* The interrupt source needs to be enabled, but masked, to prevent the
* CPU from receiving it.
*/
iowrite32(ioread32(r8a779a0_sysc_base + SYSCIER(reg_idx)) | isr_mask,
r8a779a0_sysc_base + SYSCIER(reg_idx));
iowrite32(ioread32(r8a779a0_sysc_base + SYSCIMR(reg_idx)) | isr_mask,
r8a779a0_sysc_base + SYSCIMR(reg_idx));
ret = clear_irq_flags(reg_idx, isr_mask);
if (ret)
goto out;
/* Submit power shutoff or resume request until it was accepted */
for (k = 0; k < PDRESR_RETRIES; k++) {
ret = r8a779a0_sysc_pwr_on_off(pdr, on);
if (ret)
goto out;
status = ioread32(r8a779a0_sysc_base + PDRESR(pdr));
if (!(status & PDRESR_ERR))
break;
udelay(PDRESR_DELAY_US);
}
if (k == PDRESR_RETRIES) {
ret = -EIO;
goto out;
}
/* Wait until the power shutoff or resume request has completed * */
ret = readl_poll_timeout_atomic(r8a779a0_sysc_base + SYSCISCR(reg_idx),
val, (val & isr_mask),
SYSCISR_DELAY_US, SYSCISR_TIMEOUT);
if (ret < 0) {
ret = -EIO;
goto out;
}
/* Clear interrupt flags */
ret = clear_irq_flags(reg_idx, isr_mask);
if (ret)
goto out;
out:
spin_unlock_irqrestore(&r8a779a0_sysc_lock, flags);
pr_debug("sysc power %s domain %d: %08x -> %d\n", on ? "on" : "off",
pdr, ioread32(r8a779a0_sysc_base + SYSCISCR(reg_idx)), ret);
return ret;
}
static bool r8a779a0_sysc_power_is_off(u8 pdr)
{
unsigned int st;
st = ioread32(r8a779a0_sysc_base + PDRSR(pdr));
if (st & PDRSR_OFF)
return true;
return false;
}
struct r8a779a0_sysc_pd {
struct generic_pm_domain genpd;
u8 pdr;
unsigned int flags;
char name[];
};
static inline struct r8a779a0_sysc_pd *to_r8a779a0_pd(struct generic_pm_domain *d)
{
return container_of(d, struct r8a779a0_sysc_pd, genpd);
}
static int r8a779a0_sysc_pd_power_off(struct generic_pm_domain *genpd)
{
struct r8a779a0_sysc_pd *pd = to_r8a779a0_pd(genpd);
pr_debug("%s: %s\n", __func__, genpd->name);
return r8a779a0_sysc_power(pd->pdr, false);
}
static int r8a779a0_sysc_pd_power_on(struct generic_pm_domain *genpd)
{
struct r8a779a0_sysc_pd *pd = to_r8a779a0_pd(genpd);
pr_debug("%s: %s\n", __func__, genpd->name);
return r8a779a0_sysc_power(pd->pdr, true);
}
static int __init r8a779a0_sysc_pd_setup(struct r8a779a0_sysc_pd *pd)
{
struct generic_pm_domain *genpd = &pd->genpd;
const char *name = pd->genpd.name;
int error;
if (pd->flags & PD_CPU) {
/*
* This domain contains a CPU core and therefore it should
* only be turned off if the CPU is not in use.
*/
pr_debug("PM domain %s contains %s\n", name, "CPU");
genpd->flags |= GENPD_FLAG_ALWAYS_ON;
} else if (pd->flags & PD_SCU) {
/*
* This domain contains an SCU and cache-controller, and
* therefore it should only be turned off if the CPU cores are
* not in use.
*/
pr_debug("PM domain %s contains %s\n", name, "SCU");
genpd->flags |= GENPD_FLAG_ALWAYS_ON;
} else if (pd->flags & PD_NO_CR) {
/*
* This domain cannot be turned off.
*/
genpd->flags |= GENPD_FLAG_ALWAYS_ON;
}
if (!(pd->flags & (PD_CPU | PD_SCU))) {
/* Enable Clock Domain for I/O devices */
genpd->flags |= GENPD_FLAG_PM_CLK | GENPD_FLAG_ACTIVE_WAKEUP;
genpd->attach_dev = cpg_mssr_attach_dev;
genpd->detach_dev = cpg_mssr_detach_dev;
}
genpd->power_off = r8a779a0_sysc_pd_power_off;
genpd->power_on = r8a779a0_sysc_pd_power_on;
if (pd->flags & (PD_CPU | PD_NO_CR)) {
/* Skip CPUs (handled by SMP code) and areas without control */
pr_debug("%s: Not touching %s\n", __func__, genpd->name);
goto finalize;
}
if (!r8a779a0_sysc_power_is_off(pd->pdr)) {
pr_debug("%s: %s is already powered\n", __func__, genpd->name);
goto finalize;
}
r8a779a0_sysc_power(pd->pdr, true);
finalize:
error = pm_genpd_init(genpd, &simple_qos_governor, false);
if (error)
pr_err("Failed to init PM domain %s: %d\n", name, error);
return error;
}
static const struct of_device_id r8a779a0_sysc_matches[] __initconst = {
{ .compatible = "renesas,r8a779a0-sysc", .data = &r8a779a0_sysc_info },
{ /* sentinel */ }
};
struct r8a779a0_pm_domains {
struct genpd_onecell_data onecell_data;
struct generic_pm_domain *domains[R8A779A0_PD_ALWAYS_ON + 1];
};
static struct genpd_onecell_data *r8a779a0_sysc_onecell_data;
static int __init r8a779a0_sysc_pd_init(void)
{
const struct r8a779a0_sysc_info *info;
const struct of_device_id *match;
struct r8a779a0_pm_domains *domains;
struct device_node *np;
void __iomem *base;
unsigned int i;
int error;
np = of_find_matching_node_and_match(NULL, r8a779a0_sysc_matches, &match);
if (!np)
return -ENODEV;
info = match->data;
base = of_iomap(np, 0);
if (!base) {
pr_warn("%pOF: Cannot map regs\n", np);
error = -ENOMEM;
goto out_put;
}
r8a779a0_sysc_base = base;
domains = kzalloc(sizeof(*domains), GFP_KERNEL);
if (!domains) {
error = -ENOMEM;
goto out_put;
}
domains->onecell_data.domains = domains->domains;
domains->onecell_data.num_domains = ARRAY_SIZE(domains->domains);
r8a779a0_sysc_onecell_data = &domains->onecell_data;
for (i = 0; i < info->num_areas; i++) {
const struct r8a779a0_sysc_area *area = &info->areas[i];
struct r8a779a0_sysc_pd *pd;
if (!area->name) {
/* Skip NULLified area */
continue;
}
pd = kzalloc(sizeof(*pd) + strlen(area->name) + 1, GFP_KERNEL);
if (!pd) {
error = -ENOMEM;
goto out_put;
}
strcpy(pd->name, area->name);
pd->genpd.name = pd->name;
pd->pdr = area->pdr;
pd->flags = area->flags;
error = r8a779a0_sysc_pd_setup(pd);
if (error)
goto out_put;
domains->domains[area->pdr] = &pd->genpd;
if (area->parent < 0)
continue;
error = pm_genpd_add_subdomain(domains->domains[area->parent],
&pd->genpd);
if (error) {
pr_warn("Failed to add PM subdomain %s to parent %u\n",
area->name, area->parent);
goto out_put;
}
}
error = of_genpd_add_provider_onecell(np, &domains->onecell_data);
out_put:
of_node_put(np);
return error;
}
early_initcall(r8a779a0_sysc_pd_init);