On Mon, Mar 13, 2023 at 06:10:39PM +0530, Komal Bajaj wrote:
> Add LLCC support for multi channel DDR configurations
> based off of a feature register.
>
Please elaborate more in the commit message on why this patch is needed and how
it is implemented.
> Signed-off-by: Komal Bajaj <quic_kbajaj@xxxxxxxxxxx>
> ---
> drivers/soc/qcom/llcc-qcom.c | 56 ++++++++++++++++++++++++++++--
> include/linux/soc/qcom/llcc-qcom.h | 2 ++
> 2 files changed, 55 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/soc/qcom/llcc-qcom.c b/drivers/soc/qcom/llcc-qcom.c
> index 00699a0c047e..f4d3e266c629 100644
> --- a/drivers/soc/qcom/llcc-qcom.c
> +++ b/drivers/soc/qcom/llcc-qcom.c
> @@ -17,6 +17,7 @@
> #include <linux/regmap.h>
> #include <linux/sizes.h>
> #include <linux/slab.h>
> +#include <linux/firmware/qcom/qcom_scm.h>
Sort the includes alphabetically
> #include <linux/soc/qcom/llcc-qcom.h>
>
> #define ACTIVATE BIT(0)
> @@ -924,6 +925,40 @@ static int qcom_llcc_cfg_program(struct platform_device *pdev,
> return ret;
> }
>
> +static int qcom_llcc_get_cfg_index(struct platform_device *pdev, u32 *cfg_index)
> +{
> + struct device *dev = &pdev->dev;
> + struct resource *ch_res = NULL;
No need to initialize the pointer
> +
No need of a newline
> + u32 ch_reg_sz;
> + u32 ch_reg_off;
> + u32 val;
> + int ret = 0;
> +
> + ch_res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "multi_channel_register");
> + if (ch_res) {
> + if (of_property_read_u32(dev->of_node, "multi-ch-bit-off", &ch_reg_off)) {
> + dev_err(&pdev->dev,
> + "Couldn't get offset for multi channel feature register\n");
> + return -ENODEV;
> + }
> + if (of_property_read_u32_index(dev->of_node, "multi-ch-bit-off", 1, &ch_reg_sz)) {
> + dev_err(&pdev->dev,
> + "Couldn't get size of multi channel feature register\n");
> + return -ENODEV;
> + }
> +
> + if (qcom_scm_io_readl(ch_res->start, &val)) {
You didn't mention this SCM call in the commit message. Also, for SCM, you need
to select the driver in Kconfig.
> + dev_err(&pdev->dev, "Couldn't access multi channel feature register\n");
> + ret = -EINVAL;
Catch the actual error no from qcom_scm_io_readl().
So in the case of failure, you still want to calculate cfg_index?
> + }
> + *cfg_index = (val >> ch_reg_off) & ((1 << ch_reg_sz) - 1);
> + } else
Use braces for else condition
> + *cfg_index = 0;
> +
> + return ret;
> +}
> +
> static int qcom_llcc_remove(struct platform_device *pdev)
> {
> /* Set the global pointer to a error code to avoid referencing it */
> @@ -956,10 +991,13 @@ static int qcom_llcc_probe(struct platform_device *pdev)
> struct device *dev = &pdev->dev;
> int ret, i;
> struct platform_device *llcc_edac;
> - const struct qcom_llcc_config *cfg;
> + const struct qcom_llcc_config *cfg, *entry;
> const struct llcc_slice_config *llcc_cfg;
> +
No need of newline
> u32 sz;
> + u32 cfg_index;
> u32 version;
> + u32 no_of_entries = 0;
num_entries?
>
> drv_data = devm_kzalloc(dev, sizeof(*drv_data), GFP_KERNEL);
> if (!drv_data) {
> @@ -999,8 +1037,20 @@ static int qcom_llcc_probe(struct platform_device *pdev)
> num_banks >>= LLCC_LB_CNT_SHIFT;
> drv_data->num_banks = num_banks;
>
> - llcc_cfg = cfg[0].sct_data;
> - sz = cfg[0].size;
> + ret = qcom_llcc_get_cfg_index(pdev, &cfg_index);
> + if (ret)
> + goto err;
> +
> + for (entry = cfg; entry->sct_data; entry++, no_of_entries++)
> + ;
Wrap ; in the above line itself
> + if (cfg_index >= no_of_entries) {
> + ret = -EINVAL;
> + goto err;
> + }
> +
> + drv_data->cfg_index = cfg_index;
Where is this cached value used?
Thanks,
Mani
> + llcc_cfg = cfg[cfg_index].sct_data;
> + sz = cfg[cfg_index].size;
>
> for (i = 0; i < sz; i++)
> if (llcc_cfg[i].slice_id > drv_data->max_slices)
> diff --git a/include/linux/soc/qcom/llcc-qcom.h b/include/linux/soc/qcom/llcc-qcom.h
> index ad1fd718169d..225891a02f5d 100644
> --- a/include/linux/soc/qcom/llcc-qcom.h
> +++ b/include/linux/soc/qcom/llcc-qcom.h
> @@ -125,6 +125,7 @@ struct llcc_edac_reg_offset {
> * @cfg: pointer to the data structure for slice configuration
> * @edac_reg_offset: Offset of the LLCC EDAC registers
> * @lock: mutex associated with each slice
> + * @cfg_index: index of config table if multiple configs present for a target
> * @cfg_size: size of the config data table
> * @max_slices: max slices as read from device tree
> * @num_banks: Number of llcc banks
> @@ -139,6 +140,7 @@ struct llcc_drv_data {
> const struct llcc_slice_config *cfg;
> const struct llcc_edac_reg_offset *edac_reg_offset;
> struct mutex lock;
> + u32 cfg_index;
> u32 cfg_size;
> u32 max_slices;
> u32 num_banks;
> --
> 2.39.1
>
--
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