soc: renesas: r8a779a0-sysc: Add r8a779a0 support
authorYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fri, 11 Sep 2020 07:43:52 +0000 (16:43 +0900)
committerGeert Uytterhoeven <geert+renesas@glider.be>
Wed, 16 Sep 2020 06:57:31 +0000 (08:57 +0200)
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>
drivers/soc/renesas/Kconfig
drivers/soc/renesas/Makefile
drivers/soc/renesas/r8a779a0-sysc.c [new file with mode: 0644]

index 6efa9d0..b70bbc3 100644 (file)
@@ -247,6 +247,7 @@ config ARCH_R8A77970
 config ARCH_R8A779A0
        bool "ARM64 Platform support for R-Car V3U"
        select ARCH_RCAR_GEN3
+       select SYSC_R8A779A0
        help
          This enables support for the Renesas R-Car V3U SoC.
 
@@ -338,6 +339,9 @@ config SYSC_R8A77970
        bool "System Controller support for R-Car V3M" if COMPILE_TEST
        select SYSC_RCAR
 
+config SYSC_R8A779A0
+       bool "System Controller support for R-Car V3U" if COMPILE_TEST
+
 config SYSC_RMOBILE
        bool "System Controller support for R-Mobile" if COMPILE_TEST
 
index 10a399f..9b29bed 100644 (file)
@@ -24,6 +24,7 @@ obj-$(CONFIG_SYSC_R8A77970)   += r8a77970-sysc.o
 obj-$(CONFIG_SYSC_R8A77980)    += r8a77980-sysc.o
 obj-$(CONFIG_SYSC_R8A77990)    += r8a77990-sysc.o
 obj-$(CONFIG_SYSC_R8A77995)    += r8a77995-sysc.o
+obj-$(CONFIG_SYSC_R8A779A0)    += r8a779a0-sysc.o
 ifdef CONFIG_SMP
 obj-$(CONFIG_ARCH_R9A06G032)   += r9a06g032-smp.o
 endif
diff --git a/drivers/soc/renesas/r8a779a0-sysc.c b/drivers/soc/renesas/r8a779a0-sysc.c
new file mode 100644 (file)
index 0000000..d464ffa
--- /dev/null
@@ -0,0 +1,448 @@
+// 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);