Re: [PATCH v3 2/2] ACPI: APD: Add AMD misc clock handler support

From: Daniel Kurtz
Date: Wed May 09 2018 - 11:59:34 EST


On Wed, May 9, 2018 at 4:01 AM Akshu Agrawal <akshu.agrawal@xxxxxxx> wrote:

> AMD SoC exposes clock for general purpose use. The clock registration
> is done in clk-st driver. The MMIO mapping are passed on to the
> clock driver for accessing the registers.
> The misc clock handler will create MMIO mappings to access the
> clock registers and enable the clock driver to expose the clock
> for use of drivers which will connect to it.

> Signed-off-by: Akshu Agrawal <akshu.agrawal@xxxxxxx>

Reviewed-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>

> ---
> v2: Submitted with dependent patch, removed unneeded kfree for
devm_kzalloc
> v3: used devm_ioremap and fix coccinelle warning
> drivers/acpi/acpi_apd.c | 47
+++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)

> diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c
> index d553b00..2664452 100644
> --- a/drivers/acpi/acpi_apd.c
> +++ b/drivers/acpi/acpi_apd.c
> @@ -11,6 +11,7 @@
> */

> #include <linux/clk-provider.h>
> +#include <linux/platform_data/clk-st.h>
> #include <linux/platform_device.h>
> #include <linux/pm_domain.h>
> #include <linux/clkdev.h>
> @@ -72,6 +73,47 @@ static int acpi_apd_setup(struct apd_private_data
*pdata)
> }

> #ifdef CONFIG_X86_AMD_PLATFORM_DEVICE
> +
> +static int misc_check_res(struct acpi_resource *ares, void *data)
> +{
> + struct resource res;
> +
> + return !acpi_dev_resource_memory(ares, &res);
> +}
> +
> +static int st_misc_setup(struct apd_private_data *pdata)
> +{
> + struct acpi_device *adev = pdata->adev;
> + struct platform_device *clkdev;
> + struct st_clk_data *clk_data;
> + struct resource_entry *rentry;
> + struct list_head resource_list;
> + int ret;
> +
> + clk_data = devm_kzalloc(&adev->dev, sizeof(*clk_data),
GFP_KERNEL);
> + if (!clk_data)
> + return -ENOMEM;
> +
> + INIT_LIST_HEAD(&resource_list);
> + ret = acpi_dev_get_resources(adev, &resource_list, misc_check_res,
> + NULL);
> + if (ret < 0)
> + return -ENOENT;
> +
> + list_for_each_entry(rentry, &resource_list, node) {
> + clk_data->base = devm_ioremap(&adev->dev,
rentry->res->start,
> + resource_size(rentry->res));
> + break;
> + }
> +
> + acpi_dev_free_resource_list(&resource_list);
> +
> + clkdev = platform_device_register_data(&adev->dev, "clk-st",
> + PLATFORM_DEVID_NONE,
clk_data,
> + sizeof(*clk_data));
> + return PTR_ERR_OR_ZERO(clkdev);
> +}
> +
> static const struct apd_device_desc cz_i2c_desc = {
> .setup = acpi_apd_setup,
> .fixed_clk_rate = 133000000,
> @@ -94,6 +136,10 @@ static int acpi_apd_setup(struct apd_private_data
*pdata)
> .fixed_clk_rate = 48000000,
> .properties = uart_properties,
> };
> +
> +static const struct apd_device_desc st_misc_desc = {
> + .setup = st_misc_setup,
> +};
> #endif

> #ifdef CONFIG_ARM64
> @@ -179,6 +225,7 @@ static int acpi_apd_create_device(struct acpi_device
*adev,
> { "AMD0020", APD_ADDR(cz_uart_desc) },
> { "AMDI0020", APD_ADDR(cz_uart_desc) },
> { "AMD0030", },
> + { "AMD0040", APD_ADDR(st_misc_desc)},
> #endif
> #ifdef CONFIG_ARM64
> { "APMC0D0F", APD_ADDR(xgene_i2c_desc) },
> --
> 1.9.1