2023-08-28 07:46:27

by Manivannan Sadhasivam

[permalink] [raw]
Subject: Re: [PATCH V5 1/6] scsi: ufs: qcom: Update offset for core_clk_1us_cycles

On Wed, Aug 23, 2023 at 09:14:08PM +0530, Nitin Rawat wrote:
> This Patch updates offset for core_clk_1us_cycles in DME_VS_CORE_CLK_CTRL

Please do not use "This patch" in commit message. Just reword it in imperative
form.

> register. Offset for core_clk_1us_cycles is changed from Qualcomm UFS
> Controller V4.0.0 onwards.
>
> Co-developed-by: Naveen Kumar Goud Arepalli <[email protected]>
> Signed-off-by: Naveen Kumar Goud Arepalli <[email protected]>
> Signed-off-by: Nitin Rawat <[email protected]>
> ---
> drivers/ufs/host/ufs-qcom.c | 19 ++++++++++++++-----
> drivers/ufs/host/ufs-qcom.h | 2 ++
> 2 files changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
> index f88febb23123..1108b0cd43b3 100644
> --- a/drivers/ufs/host/ufs-qcom.c
> +++ b/drivers/ufs/host/ufs-qcom.c
> @@ -1297,12 +1297,21 @@ static void ufs_qcom_exit(struct ufs_hba *hba)
> }
>
> static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
> - u32 clk_cycles)
> + u32 clk_1us_cycles)

How about "cycles_in_1us", since this value specifies "Number of clk cycles in
1us"?

> {
> - int err;
> + struct ufs_qcom_host *host = ufshcd_get_variant(hba);
> + u32 mask = DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK;
> u32 core_clk_ctrl_reg;
> + u32 offset = 0;
> + int err;
> +
> + /* Bit mask and offset changed on UFS host controller V4.0.0 onwards */

This is not offset value, but rather shift. Still, if you use bitfield macros
as I suggested below, you could get rid of this variable.

> + if (host->hw_ver.major >= 4) {
> + mask = MAX_CORE_CLK_1US_CYCLES_MASK_V4;
> + offset = MAX_CORE_CLK_1US_CYCLES_OFFSET_V4;
> + }
>
> - if (clk_cycles > DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK)
> + if (clk_1us_cycles > mask)
> return -EINVAL;

if (!FIELD_FIT(mask, cycles_in_1us))
return -ERANGE;

>
> err = ufshcd_dme_get(hba,
> @@ -1311,8 +1320,8 @@ static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
> if (err)
> return err;
>
> - core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK;
> - core_clk_ctrl_reg |= clk_cycles;
> + core_clk_ctrl_reg &= ~(mask << offset);
> + core_clk_ctrl_reg |= clk_1us_cycles << offset;
>

core_clk_ctrl_reg &= ~mask;
core_clk_ctrl_reg |= FIELD_PREP(mask, cycles_in_1us);

> /* Clear CORE_CLK_DIV_EN */
> core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT;
> diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h
> index d6f8e74bd538..a829296e11bb 100644
> --- a/drivers/ufs/host/ufs-qcom.h
> +++ b/drivers/ufs/host/ufs-qcom.h
> @@ -129,6 +129,8 @@ enum {
> #define PA_VS_CONFIG_REG1 0x9000
> #define DME_VS_CORE_CLK_CTRL 0xD002
> /* bit and mask definitions for DME_VS_CORE_CLK_CTRL attribute */

> +#define MAX_CORE_CLK_1US_CYCLES_MASK_V4 0xFFF

#define MAX_CORE_CLK_1US_CYCLES_MASK_V4 GENMASK(27, 16)
#define DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK GENMASK(7, 0)

- Mani

> +#define MAX_CORE_CLK_1US_CYCLES_OFFSET_V4 0x10
> #define DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT BIT(8)
> #define DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK 0xFF
>
> --
> 2.17.1
>

--
மணிவண்ணன் சதாசிவம்