[PATCH v5 1/6] ARM: rockchip: convert to regmap and use pmu syscon if available

[Sonny Rao]

On Wed, Oct 15, 2014 at 10:23 AM, Kever Yang <kever.yang at rock-chips.com> wrote:
> From: Heiko Stuebner <heiko at sntech.de>
>
> The pmu register space is - like the GRF - shared by quite some peripherals.
> On the rk3188 and rk3288 even parts of the pinctrl are living there.
> Therefore we normally shouldn't map it a second time when the syscon
> does this already.
>
> Therefore convert the cpu power-domain handling to access the pmu via a
> regmap and at first try to get it via the syscon interface.
> Getting this syscon will only fail if the pmu node does not have the
> "syscon" compatible and thus does not get shared with other drivers.
>
> In this case we map it like before and create the necessary regmap on
> top of it.
>
> Signed-off-by: Heiko Stuebner <heiko at sntech.de>
> Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> ---
>
> Changes in v5: None
> Changes in v4: None
> Changes in v3:
> - add this patch in version 3
>
> Changes in v2: None
>
>  arch/arm/mach-rockchip/platsmp.c | 104 +++++++++++++++++++++++++++++----------
>  1 file changed, 78 insertions(+), 26 deletions(-)
>
> diff --git a/arch/arm/mach-rockchip/platsmp.c b/arch/arm/mach-rockchip/platsmp.c
> index 189684f..4c36fbf 100644
> --- a/arch/arm/mach-rockchip/platsmp.c
> +++ b/arch/arm/mach-rockchip/platsmp.c
> @@ -19,6 +19,8 @@
>  #include <linux/io.h>
>  #include <linux/of.h>
>  #include <linux/of_address.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
>
>  #include <asm/cacheflush.h>
>  #include <asm/cp15.h>
> @@ -37,23 +39,42 @@ static int ncores;
>
>  #define PMU_PWRDN_SCU          4
>
> -static void __iomem *pmu_base_addr;
> +static struct regmap *pmu;
>
> -static inline bool pmu_power_domain_is_on(int pd)
> +static int pmu_power_domain_is_on(int pd)
>  {
> -       return !(readl_relaxed(pmu_base_addr + PMU_PWRDN_ST) & BIT(pd));
> +       u32 val;
> +       int ret;
> +
> +       ret = regmap_read(pmu, PMU_PWRDN_ST, &val);
> +       if (ret < 0)
> +               return ret;
> +
> +       return !(val & BIT(pd));
>  }
>
> -static void pmu_set_power_domain(int pd, bool on)
> +static int pmu_set_power_domain(int pd, bool on)
>  {
> -       u32 val = readl_relaxed(pmu_base_addr + PMU_PWRDN_CON);
> -       if (on)
> -               val &= ~BIT(pd);
> -       else
> -               val |=  BIT(pd);
> -       writel(val, pmu_base_addr + PMU_PWRDN_CON);
> -
> -       while (pmu_power_domain_is_on(pd) != on) { }
> +       u32 val = (on) ? 0 : BIT(pd);
> +       int ret;
> +
> +       ret = regmap_update_bits(pmu, PMU_PWRDN_CON, BIT(pd), val);
> +       if (ret < 0) {
> +               pr_err("%s: could not update power domain\n", __func__);
> +               return ret;
> +       }
> +
> +       ret = -1;
> +       while (ret != on) {
> +               ret = pmu_power_domain_is_on(pd);
> +               if (ret < 0) {
> +                       pr_err("%s: could not read power domain state\n",
> +                                __func__);
> +                       return ret;
> +               }
> +       }
> +
> +       return 0;
>  }
>
>  /*
> @@ -63,7 +84,7 @@ static void pmu_set_power_domain(int pd, bool on)
>  static int __cpuinit rockchip_boot_secondary(unsigned int cpu,
>                                              struct task_struct *idle)
>  {
> -       if (!sram_base_addr || !pmu_base_addr) {
> +       if (!sram_base_addr || !pmu) {
>                 pr_err("%s: sram or pmu missing for cpu boot\n", __func__);
>                 return -ENXIO;
>         }
> @@ -75,9 +96,7 @@ static int __cpuinit rockchip_boot_secondary(unsigned int cpu,
>         }
>
>         /* start the core */
> -       pmu_set_power_domain(0 + cpu, true);
> -
> -       return 0;
> +       return pmu_set_power_domain(0 + cpu, true);
>  }
>
>  /**
> @@ -125,6 +144,48 @@ static int __init rockchip_smp_prepare_sram(struct device_node *node)
>         return 0;
>  }
>
> +static struct regmap_config rockchip_pmu_regmap_config = {
> +       .reg_bits = 32,
> +       .val_bits = 32,
> +       .reg_stride = 4,
> +};
> +
> +static int __init rockchip_smp_prepare_pmu(void)
> +{
> +       struct device_node *node;
> +       void __iomem *pmu_base;
> +
> +       pmu = syscon_regmap_lookup_by_compatible("rockchip,rk3066-pmu");
> +       if (!IS_ERR(pmu))
> +               return 0;
> +
> +       /* fallback, create our own regmap for the pmu area */

I don't think you need this fallback, the syscon driver should take
care of mapping and creating the regmap for you -- assuming that the
pmu node has the "syscon" property.

> +       pmu = NULL;
> +       node = of_find_compatible_node(NULL, NULL, "rockchip,rk3066-pmu");
> +       if (!node) {
> +               pr_err("%s: could not find pmu dt node\n", __func__);
> +               return -ENODEV;
> +       }
> +
> +       pmu_base = of_iomap(node, 0);
> +       if (!pmu_base) {
> +               pr_err("%s: could not map pmu registers\n", __func__);
> +               return -ENOMEM;
> +       }
> +
> +       pmu = regmap_init_mmio(NULL, pmu_base, &rockchip_pmu_regmap_config);
> +       if (IS_ERR(pmu)) {
> +               int ret = PTR_ERR(pmu);
> +
> +               iounmap(pmu_base);
> +               pmu = NULL;
> +               pr_err("%s: regmap init failed\n", __func__);
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
>  static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus)
>  {
>         struct device_node *node;
> @@ -151,17 +212,8 @@ static void __init rockchip_smp_prepare_cpus(unsigned int max_cpus)
>         if (rockchip_smp_prepare_sram(node))
>                 return;
>
> -       node = of_find_compatible_node(NULL, NULL, "rockchip,rk3066-pmu");
> -       if (!node) {
> -               pr_err("%s: could not find pmu dt node\n", __func__);
> +       if (rockchip_smp_prepare_pmu())
>                 return;
> -       }
> -
> -       pmu_base_addr = of_iomap(node, 0);
> -       if (!pmu_base_addr) {
> -               pr_err("%s: could not map pmu registers\n", __func__);
> -               return;
> -       }
>
>         /* enable the SCU power domain */
>         pmu_set_power_domain(PMU_PWRDN_SCU, true);
> --
> 1.9.1
>