linux/drivers/soc/amlogic/meson-gx-pwrc-vpu.c
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   1/*
   2 * Copyright (c) 2017 BayLibre, SAS
   3 * Author: Neil Armstrong <narmstrong@baylibre.com>
   4 *
   5 * SPDX-License-Identifier: GPL-2.0+
   6 */
   7
   8#include <linux/of_address.h>
   9#include <linux/platform_device.h>
  10#include <linux/pm_domain.h>
  11#include <linux/bitfield.h>
  12#include <linux/regmap.h>
  13#include <linux/mfd/syscon.h>
  14#include <linux/reset.h>
  15#include <linux/clk.h>
  16
  17/* AO Offsets */
  18
  19#define AO_RTI_GEN_PWR_SLEEP0           (0x3a << 2)
  20
  21#define GEN_PWR_VPU_HDMI                BIT(8)
  22#define GEN_PWR_VPU_HDMI_ISO            BIT(9)
  23
  24/* HHI Offsets */
  25
  26#define HHI_MEM_PD_REG0                 (0x40 << 2)
  27#define HHI_VPU_MEM_PD_REG0             (0x41 << 2)
  28#define HHI_VPU_MEM_PD_REG1             (0x42 << 2)
  29
  30struct meson_gx_pwrc_vpu {
  31        struct generic_pm_domain genpd;
  32        struct regmap *regmap_ao;
  33        struct regmap *regmap_hhi;
  34        struct reset_control *rstc;
  35        struct clk *vpu_clk;
  36        struct clk *vapb_clk;
  37};
  38
  39static inline
  40struct meson_gx_pwrc_vpu *genpd_to_pd(struct generic_pm_domain *d)
  41{
  42        return container_of(d, struct meson_gx_pwrc_vpu, genpd);
  43}
  44
  45static int meson_gx_pwrc_vpu_power_off(struct generic_pm_domain *genpd)
  46{
  47        struct meson_gx_pwrc_vpu *pd = genpd_to_pd(genpd);
  48        int i;
  49
  50        regmap_update_bits(pd->regmap_ao, AO_RTI_GEN_PWR_SLEEP0,
  51                           GEN_PWR_VPU_HDMI_ISO, GEN_PWR_VPU_HDMI_ISO);
  52        udelay(20);
  53
  54        /* Power Down Memories */
  55        for (i = 0; i < 32; i += 2) {
  56                regmap_update_bits(pd->regmap_hhi, HHI_VPU_MEM_PD_REG0,
  57                                   0x2 << i, 0x3 << i);
  58                udelay(5);
  59        }
  60        for (i = 0; i < 32; i += 2) {
  61                regmap_update_bits(pd->regmap_hhi, HHI_VPU_MEM_PD_REG1,
  62                                   0x2 << i, 0x3 << i);
  63                udelay(5);
  64        }
  65        for (i = 8; i < 16; i++) {
  66                regmap_update_bits(pd->regmap_hhi, HHI_MEM_PD_REG0,
  67                                   BIT(i), BIT(i));
  68                udelay(5);
  69        }
  70        udelay(20);
  71
  72        regmap_update_bits(pd->regmap_ao, AO_RTI_GEN_PWR_SLEEP0,
  73                           GEN_PWR_VPU_HDMI, GEN_PWR_VPU_HDMI);
  74
  75        msleep(20);
  76
  77        clk_disable_unprepare(pd->vpu_clk);
  78        clk_disable_unprepare(pd->vapb_clk);
  79
  80        return 0;
  81}
  82
  83static int meson_gx_pwrc_vpu_setup_clk(struct meson_gx_pwrc_vpu *pd)
  84{
  85        int ret;
  86
  87        ret = clk_prepare_enable(pd->vpu_clk);
  88        if (ret)
  89                return ret;
  90
  91        ret = clk_prepare_enable(pd->vapb_clk);
  92        if (ret)
  93                clk_disable_unprepare(pd->vpu_clk);
  94
  95        return ret;
  96}
  97
  98static int meson_gx_pwrc_vpu_power_on(struct generic_pm_domain *genpd)
  99{
 100        struct meson_gx_pwrc_vpu *pd = genpd_to_pd(genpd);
 101        int ret;
 102        int i;
 103
 104        regmap_update_bits(pd->regmap_ao, AO_RTI_GEN_PWR_SLEEP0,
 105                           GEN_PWR_VPU_HDMI, 0);
 106        udelay(20);
 107
 108        /* Power Up Memories */
 109        for (i = 0; i < 32; i += 2) {
 110                regmap_update_bits(pd->regmap_hhi, HHI_VPU_MEM_PD_REG0,
 111                                   0x2 << i, 0);
 112                udelay(5);
 113        }
 114
 115        for (i = 0; i < 32; i += 2) {
 116                regmap_update_bits(pd->regmap_hhi, HHI_VPU_MEM_PD_REG1,
 117                                   0x2 << i, 0);
 118                udelay(5);
 119        }
 120
 121        for (i = 8; i < 16; i++) {
 122                regmap_update_bits(pd->regmap_hhi, HHI_MEM_PD_REG0,
 123                                   BIT(i), 0);
 124                udelay(5);
 125        }
 126        udelay(20);
 127
 128        ret = reset_control_assert(pd->rstc);
 129        if (ret)
 130                return ret;
 131
 132        regmap_update_bits(pd->regmap_ao, AO_RTI_GEN_PWR_SLEEP0,
 133                           GEN_PWR_VPU_HDMI_ISO, 0);
 134
 135        ret = reset_control_deassert(pd->rstc);
 136        if (ret)
 137                return ret;
 138
 139        ret = meson_gx_pwrc_vpu_setup_clk(pd);
 140        if (ret)
 141                return ret;
 142
 143        return 0;
 144}
 145
 146static bool meson_gx_pwrc_vpu_get_power(struct meson_gx_pwrc_vpu *pd)
 147{
 148        u32 reg;
 149
 150        regmap_read(pd->regmap_ao, AO_RTI_GEN_PWR_SLEEP0, &reg);
 151
 152        return (reg & GEN_PWR_VPU_HDMI);
 153}
 154
 155static struct meson_gx_pwrc_vpu vpu_hdmi_pd = {
 156        .genpd = {
 157                .name = "vpu_hdmi",
 158                .power_off = meson_gx_pwrc_vpu_power_off,
 159                .power_on = meson_gx_pwrc_vpu_power_on,
 160        },
 161};
 162
 163static int meson_gx_pwrc_vpu_probe(struct platform_device *pdev)
 164{
 165        struct regmap *regmap_ao, *regmap_hhi;
 166        struct reset_control *rstc;
 167        struct clk *vpu_clk;
 168        struct clk *vapb_clk;
 169        bool powered_off;
 170        int ret;
 171
 172        regmap_ao = syscon_node_to_regmap(of_get_parent(pdev->dev.of_node));
 173        if (IS_ERR(regmap_ao)) {
 174                dev_err(&pdev->dev, "failed to get regmap\n");
 175                return PTR_ERR(regmap_ao);
 176        }
 177
 178        regmap_hhi = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 179                                                     "amlogic,hhi-sysctrl");
 180        if (IS_ERR(regmap_hhi)) {
 181                dev_err(&pdev->dev, "failed to get HHI regmap\n");
 182                return PTR_ERR(regmap_hhi);
 183        }
 184
 185        rstc = devm_reset_control_array_get(&pdev->dev, false, false);
 186        if (IS_ERR(rstc)) {
 187                if (PTR_ERR(rstc) != -EPROBE_DEFER)
 188                        dev_err(&pdev->dev, "failed to get reset lines\n");
 189                return PTR_ERR(rstc);
 190        }
 191
 192        vpu_clk = devm_clk_get(&pdev->dev, "vpu");
 193        if (IS_ERR(vpu_clk)) {
 194                dev_err(&pdev->dev, "vpu clock request failed\n");
 195                return PTR_ERR(vpu_clk);
 196        }
 197
 198        vapb_clk = devm_clk_get(&pdev->dev, "vapb");
 199        if (IS_ERR(vapb_clk)) {
 200                dev_err(&pdev->dev, "vapb clock request failed\n");
 201                return PTR_ERR(vapb_clk);
 202        }
 203
 204        vpu_hdmi_pd.regmap_ao = regmap_ao;
 205        vpu_hdmi_pd.regmap_hhi = regmap_hhi;
 206        vpu_hdmi_pd.rstc = rstc;
 207        vpu_hdmi_pd.vpu_clk = vpu_clk;
 208        vpu_hdmi_pd.vapb_clk = vapb_clk;
 209
 210        powered_off = meson_gx_pwrc_vpu_get_power(&vpu_hdmi_pd);
 211
 212        /* If already powered, sync the clock states */
 213        if (!powered_off) {
 214                ret = meson_gx_pwrc_vpu_setup_clk(&vpu_hdmi_pd);
 215                if (ret)
 216                        return ret;
 217        }
 218
 219        pm_genpd_init(&vpu_hdmi_pd.genpd, &pm_domain_always_on_gov,
 220                      powered_off);
 221
 222        return of_genpd_add_provider_simple(pdev->dev.of_node,
 223                                            &vpu_hdmi_pd.genpd);
 224}
 225
 226static void meson_gx_pwrc_vpu_shutdown(struct platform_device *pdev)
 227{
 228        bool powered_off;
 229
 230        powered_off = meson_gx_pwrc_vpu_get_power(&vpu_hdmi_pd);
 231        if (!powered_off)
 232                meson_gx_pwrc_vpu_power_off(&vpu_hdmi_pd.genpd);
 233}
 234
 235static const struct of_device_id meson_gx_pwrc_vpu_match_table[] = {
 236        { .compatible = "amlogic,meson-gx-pwrc-vpu" },
 237        { /* sentinel */ }
 238};
 239
 240static struct platform_driver meson_gx_pwrc_vpu_driver = {
 241        .probe  = meson_gx_pwrc_vpu_probe,
 242        .shutdown = meson_gx_pwrc_vpu_shutdown,
 243        .driver = {
 244                .name           = "meson_gx_pwrc_vpu",
 245                .of_match_table = meson_gx_pwrc_vpu_match_table,
 246        },
 247};
 248builtin_platform_driver(meson_gx_pwrc_vpu_driver);
 249