Re: [PATCH 2/4] soc: Mediatek: Add SCPSYS power domain driver

[Matthias Brugger <matthias.bgg@gmail.com>]

2015-03-10 16:41 GMT+01:00 Sascha Hauer <s.hauer@pengutronix.de>:
> This adds a power domain driver for the Mediatek SCPSYS unit.
>
> The System Control Processor System (SCPSYS) has several power
> management related tasks in the system. The tasks include thermal
> measurement, dynamic voltage frequency scaling (DVFS), interrupt
> filter and lowlevel sleep control. The System Power Manager (SPM)
> inside the SCPSYS is for the MTCMOS power domain control.
>
> For now this driver only adds power domain support, the more
> advanced features are not yet supported. The driver implements
> the generic PM domain device tree bindings, the first user will
> most likely be the Mediatek AFE audio driver.
>
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
>  drivers/soc/mediatek/Kconfig             |   6 +
>  drivers/soc/mediatek/Makefile            |   1 +
>  drivers/soc/mediatek/mtk-scpsys.c        | 345 +++++++++++++++++++++++++++++++
>  include/dt-bindings/power/mt8173-power.h |  15 ++
>  4 files changed, 367 insertions(+)
>  create mode 100644 drivers/soc/mediatek/mtk-scpsys.c
>  create mode 100644 include/dt-bindings/power/mt8173-power.h
>
> diff --git a/drivers/soc/mediatek/Kconfig b/drivers/soc/mediatek/Kconfig
> index bcdb22d..1d34819 100644
> --- a/drivers/soc/mediatek/Kconfig
> +++ b/drivers/soc/mediatek/Kconfig
> @@ -9,3 +9,9 @@ config MTK_PMIC_WRAP
>           Say yes here to add support for MediaTek PMIC Wrapper found
>           on different MediaTek SoCs. The PMIC wrapper is a proprietary
>           hardware to connect the PMIC.
> +
> +config MTK_SCPSYS
> +       tristate "MediaTek SCPSYS Support"
> +       help
> +         Say yes here to add support for the MediaTek SCPSYS power domain
> +         driver.
> diff --git a/drivers/soc/mediatek/Makefile b/drivers/soc/mediatek/Makefile
> index ecaf4de..ce88693 100644
> --- a/drivers/soc/mediatek/Makefile
> +++ b/drivers/soc/mediatek/Makefile
> @@ -1 +1,2 @@
>  obj-$(CONFIG_MTK_PMIC_WRAP) += mtk-pmic-wrap.o
> +obj-$(CONFIG_MTK_SCPSYS) += mtk-scpsys.o
> diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
> new file mode 100644
> index 0000000..a72ac51
> --- /dev/null
> +++ b/drivers/soc/mediatek/mtk-scpsys.c
> @@ -0,0 +1,345 @@
> +/*
> + * Copyright (c) 2015 Pengutronix, Sascha Hauer <kernel@pengutronix.de>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/pm_domain.h>
> +#include <linux/delay.h>
> +#include <dt-bindings/power/mt8173-power.h>
> +#include <linux/mfd/syscon.h>
> +
> +#define SPM_VDE_PWR_CON                        0x0210
> +#define SPM_MFG_PWR_CON                        0x0214
> +#define SPM_VEN_PWR_CON                        0x0230
> +#define SPM_ISP_PWR_CON                        0x0238
> +#define SPM_DIS_PWR_CON                        0x023c
> +#define SPM_VEN2_PWR_CON               0x0298
> +#define SPM_AUDIO_PWR_CON              0x029c
> +#define SPM_MFG_2D_PWR_CON             0x02c0
> +#define SPM_MFG_ASYNC_PWR_CON          0x02c4
> +#define SPM_USB_PWR_CON                        0x02cc
> +#define SPM_PWR_STATUS                 0x060c
> +#define SPM_PWR_STATUS_2ND             0x0610
> +
> +#define PWR_RST_B_BIT                  BIT(0)
> +#define PWR_ISO_BIT                    BIT(1)
> +#define PWR_ON_BIT                     BIT(2)
> +#define PWR_ON_2ND_BIT                 BIT(3)
> +#define PWR_CLK_DIS_BIT                        BIT(4)
> +
> +#define DIS_PWR_STA_MASK               BIT(3)
> +#define MFG_PWR_STA_MASK               BIT(4)
> +#define ISP_PWR_STA_MASK               BIT(5)
> +#define VDE_PWR_STA_MASK               BIT(7)
> +#define VEN2_PWR_STA_MASK              BIT(20)
> +#define VEN_PWR_STA_MASK               BIT(21)
> +#define MFG_2D_PWR_STA_MASK            BIT(22)
> +#define MFG_ASYNC_PWR_STA_MASK         BIT(23)
> +#define AUDIO_PWR_STA_MASK             BIT(24)
> +#define USB_PWR_STA_MASK               BIT(25)
> +
> +struct scp_domain_data {
> +       const char *name;
> +       u32 sta_mask;
> +       int ctl_offs;
> +       u32 sram_pdn_bits;
> +       u32 sram_pdn_ack_bits;
> +       int id;
> +};
> +
> +static struct scp_domain_data scp_domain_data[] = {
> +       {
> +               .id = MT8173_POWER_DOMAIN_VDE,
> +               .name = "vde",
> +               .sta_mask = VDE_PWR_STA_MASK,
> +               .ctl_offs = SPM_VDE_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(12, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_MFG,
> +               .name = "mfg",
> +               .sta_mask = MFG_PWR_STA_MASK,
> +               .ctl_offs = SPM_MFG_PWR_CON,
> +               .sram_pdn_bits = GENMASK(13, 8),
> +               .sram_pdn_ack_bits = GENMASK(21, 16),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_VEN,
> +               .name = "ven",
> +               .sta_mask = VEN_PWR_STA_MASK,
> +               .ctl_offs = SPM_VEN_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(15, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_ISP,
> +               .name = "isp",
> +               .sta_mask = ISP_PWR_STA_MASK,
> +               .ctl_offs = SPM_ISP_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(13, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_DIS,
> +               .name = "dis",
> +               .sta_mask = DIS_PWR_STA_MASK,
> +               .ctl_offs = SPM_DIS_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(12, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_VEN2,
> +               .name = "ven2",
> +               .sta_mask = VEN2_PWR_STA_MASK,
> +               .ctl_offs = SPM_VEN2_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(15, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_AUDIO,
> +               .name = "audio",
> +               .sta_mask = AUDIO_PWR_STA_MASK,
> +               .ctl_offs = SPM_AUDIO_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(15, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_MFG_2D,
> +               .name = "mfg_2d",
> +               .sta_mask = MFG_2D_PWR_STA_MASK,
> +               .ctl_offs = SPM_MFG_2D_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(13, 12),
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_MFG_ASYNC,
> +               .name = "mfg_async",
> +               .sta_mask = MFG_ASYNC_PWR_STA_MASK,
> +               .ctl_offs = SPM_MFG_ASYNC_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = 0,
> +       }, {
> +               .id = MT8173_POWER_DOMAIN_USB,
> +               .name = "usb",
> +               .sta_mask = USB_PWR_STA_MASK,
> +               .ctl_offs = SPM_USB_PWR_CON,
> +               .sram_pdn_bits = GENMASK(11, 8),
> +               .sram_pdn_ack_bits = GENMASK(15, 12),
> +       },
> +};
> +
> +#define NUM_DOMAINS    ARRAY_SIZE(scp_domain_data)
> +
> +struct scp;
> +
> +struct scp_domain {
> +       struct generic_pm_domain pmd;
> +       struct scp_domain_data *data;
> +       struct scp *scp;
> +};
> +
> +struct scp {
> +       struct scp_domain domains[NUM_DOMAINS];
> +       struct generic_pm_domain *pmd[NUM_DOMAINS];
> +       struct genpd_onecell_data pd_data;
> +       struct device *dev;
> +       void __iomem *base;
> +};
> +
> +static int scpsys_power_on(struct generic_pm_domain *genpd)
> +{
> +       struct scp_domain *scpd = container_of(genpd, struct scp_domain, pmd);
> +       struct scp *scp = scpd->scp;
> +       struct scp_domain_data *data = scpd->data;
> +       unsigned long expired;
> +       void __iomem *ctl_addr = scpd->scp->base + data->ctl_offs;
> +       u32 sram_pdn_ack = data->sram_pdn_ack_bits;
> +       u32 val;
> +       int ret;
> +
> +       val = readl(ctl_addr);
> +       val |= PWR_ON_BIT;
> +       writel(val, ctl_addr);
> +       val |= PWR_ON_2ND_BIT;
> +       writel(val, ctl_addr);
> +
> +       /* wait until PWR_ACK = 1 */
> +       expired = jiffies + HZ;
> +       while (!(readl(scp->base + SPM_PWR_STATUS) & data->sta_mask) ||
> +                       !(readl(scp->base + SPM_PWR_STATUS_2ND) & data->sta_mask)) {
> +               cpu_relax();
> +               if (time_after(jiffies, expired)) {
> +                       ret = -EIO;
> +                       goto out;
> +               }
> +       }
> +
> +       val &= ~PWR_CLK_DIS_BIT;
> +       writel(val, ctl_addr);
> +
> +       val &= ~PWR_ISO_BIT;
> +       writel(val, ctl_addr);
> +
> +       val |= PWR_RST_B_BIT;
> +       writel(val, ctl_addr);
> +
> +       val &= ~data->sram_pdn_bits;
> +       writel(val, ctl_addr);
> +
> +       /* wait until SRAM_PDN_ACK all 0 */
> +       expired = jiffies + HZ;
> +       while (sram_pdn_ack && (readl(ctl_addr) & sram_pdn_ack)) {

I think "sram_pdn_ack &&" was added accidently here. It is always
bigger then zero.

> +               cpu_relax();
> +               if (time_after(jiffies, expired)) {
> +                       ret = -EIO;
> +                       goto out;
> +               }
> +       }
> +
> +       return 0;
> +out:
> +       dev_err(scp->dev, "Failed to power on domain %s\n", scpd->data->name);
> +
> +       return ret;
> +}
> +
> +static int scpsys_power_off(struct generic_pm_domain *genpd)
> +{
> +       struct scp_domain *scpd = container_of(genpd, struct scp_domain, pmd);
> +       struct scp *scp = scpd->scp;
> +       struct scp_domain_data *data = scpd->data;
> +       unsigned long expired;
> +       void __iomem *ctl_addr = scpd->scp->base + data->ctl_offs;
> +       u32 sram_pdn_ack = data->sram_pdn_ack_bits;
> +       u32 val;
> +       int ret;
> +
> +       val = readl(ctl_addr);
> +       val |= data->sram_pdn_bits;
> +       writel(val, ctl_addr);
> +
> +       /* wait until SRAM_PDN_ACK all 1 */
> +       expired = jiffies + HZ;
> +       while ((readl(ctl_addr) & sram_pdn_ack) != sram_pdn_ack) {
> +               cpu_relax();
> +               if (time_after(jiffies, expired)) {
> +                       ret = -EIO;
> +                       goto out;
> +               }
> +       }
> +
> +       val |= PWR_ISO_BIT;
> +       writel(val, ctl_addr);
> +
> +       val &= ~PWR_RST_B_BIT;
> +       writel(val, ctl_addr);
> +
> +       val |= PWR_CLK_DIS_BIT;
> +       writel(val, ctl_addr);
> +
> +       val &= ~PWR_ON_BIT;
> +       writel(val, ctl_addr);
> +
> +       val &= ~PWR_ON_2ND_BIT;
> +       writel(val, ctl_addr);
> +
> +       /* wait until PWR_ACK = 0 */
> +       expired = jiffies + HZ;
> +       while ((readl(scp->base + SPM_PWR_STATUS) & data->sta_mask) ||
> +                       (readl(scp->base + SPM_PWR_STATUS_2ND) & data->sta_mask)) {
> +               cpu_relax();
> +               if (time_after(jiffies, expired)) {
> +                       ret = -EIO;
> +                       goto out;
> +               }
> +       }
> +
> +       return 0;
> +
> +out:
> +       dev_err(scp->dev, "Failed to power on domain %s\n", scpd->data->name);

typo, this shoudl be "power off domain"