On 09/08/18 12:09, Sayali Lokhande wrote:
> From: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
>
> UFS host supplies the reference clock to UFS device and UFS device
> specification allows host to provide one of the 4 frequencies (19.2 MHz,
> 26 MHz, 38.4 MHz, 52 MHz) for reference clock. Host should set the
> device reference clock frequency setting in the device based on what
> frequency it is supplying to UFS device.
>
> Signed-off-by: Subhash Jadavani <subhashj@xxxxxxxxxxxxxx>
> Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> Signed-off-by: Sayali Lokhande <sayalil@xxxxxxxxxxxxxx>
> ---
> drivers/scsi/ufs/ufs.h | 21 ++++++++++
> drivers/scsi/ufs/ufshcd-pltfrm.c | 2 +
> drivers/scsi/ufs/ufshcd.c | 89 ++++++++++++++++++++++++++++++++++++++++
> drivers/scsi/ufs/ufshcd.h | 2 +
> 4 files changed, 114 insertions(+)
>
> diff --git a/drivers/scsi/ufs/ufs.h b/drivers/scsi/ufs/ufs.h
> index 14e5bf7..c555ac0 100644
> --- a/drivers/scsi/ufs/ufs.h
> +++ b/drivers/scsi/ufs/ufs.h
> @@ -378,6 +378,27 @@ enum query_opcode {
> UPIU_QUERY_OPCODE_TOGGLE_FLAG = 0x8,
> };
>
> +/* bRefClkFreq attribute values */
> +enum ref_clk_freq_hz {
> + REF_CLK_FREQ_19_2_MHZ = 19200000,
> + REF_CLK_FREQ_26_MHZ = 26000000,
> + REF_CLK_FREQ_38_4_MHZ = 38400000,
> + REF_CLK_FREQ_52_MHZ = 52000000,
> +};
> +
> +enum bref_clk_freq {
> + bREF_CLK_FREQ_0, /* 19.2 MHz */
> + bREF_CLK_FREQ_1, /* 26 MHz */
> + bREF_CLK_FREQ_2, /* 38.4 MHz */
> + bREF_CLK_FREQ_3, /* 52 MHz */
> + bREF_CLK_FREQ_INVAL,
> +};
> +
> +struct ufs_ref_clk {
> + enum ref_clk_freq_hz freq_hz;
> + enum bref_clk_freq val;
> +};
> +
> /* Query response result code */
> enum {
> QUERY_RESULT_SUCCESS = 0x00,
> diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c
> index e82bde0..0953563 100644
> --- a/drivers/scsi/ufs/ufshcd-pltfrm.c
> +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c
> @@ -343,6 +343,8 @@ int ufshcd_pltfrm_init(struct platform_device *pdev,
> pm_runtime_set_active(&pdev->dev);
> pm_runtime_enable(&pdev->dev);
>
> + ufshcd_parse_dev_ref_clk_freq(hba);
> +
> ufshcd_init_lanes_per_dir(hba);
>
> err = ufshcd_init(hba, mmio_base, irq);
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index c5b1bf1..0cbdde7 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -6296,6 +6296,89 @@ static void ufshcd_def_desc_sizes(struct ufs_hba *hba)
> hba->desc_size.hlth_desc = QUERY_DESC_HEALTH_DEF_SIZE;
> }
>
> +static struct ufs_ref_clk ufs_ref_clk_freqs[] = {
> + {REF_CLK_FREQ_19_2_MHZ, bREF_CLK_FREQ_0},
> + {REF_CLK_FREQ_26_MHZ, bREF_CLK_FREQ_1},
> + {REF_CLK_FREQ_38_4_MHZ, bREF_CLK_FREQ_2},
> + {REF_CLK_FREQ_52_MHZ, bREF_CLK_FREQ_3},
> +};
> +
> +static inline enum bref_clk_freq
> +ufs_get_bref_clk_for_ref_clk_freq_hz(u32 freq)
> +{
> + enum bref_clk_freq val;
> +
> + for (val = bREF_CLK_FREQ_0; val <= bREF_CLK_FREQ_3; val++)
> + if (ufs_ref_clk_freqs[val].freq_hz == freq)
> + return val;
> +
> + /* if no match found, return invalid*/
> + return bREF_CLK_FREQ_INVAL;
> +}
> +
> +void ufshcd_parse_dev_ref_clk_freq(struct ufs_hba *hba)
> +{
> + struct device *dev = hba->dev;
> + struct device_node *np = dev->of_node;
> + struct clk *refclk = NULL;
> + u32 freq = 0;
> +
> + if (!np)
> + return;
> +
> + hba->dev_ref_clk_freq = bREF_CLK_FREQ_INVAL;
> +
> + refclk = of_clk_get_by_name(np, "ref_clk");
What about users that don't use DT?
> + if (!refclk)
> + return;
> +
> + freq = clk_get_rate(refclk);
> + if (freq > REF_CLK_FREQ_52_MHZ) {
> + dev_err(hba->dev,
> + "%s: invalid ref_clk setting = %d\n",
> + __func__, freq);
> + return;
> + }
> +
> + hba->dev_ref_clk_freq =
> + ufs_get_bref_clk_for_ref_clk_freq_hz(freq);
> +}
> +
> +static int ufshcd_set_dev_ref_clk(struct ufs_hba *hba)
> +{
> + int err = 0;
> + int ref_clk = -1;
> +
> + err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_READ_ATTR,
> + QUERY_ATTR_IDN_REF_CLK_FREQ, 0, 0, &ref_clk);
> +
> + if (err) {
> + dev_err(hba->dev, "%s: failed reading bRefClkFreq. err = %d\n",
> + __func__, err);
> + goto out;
> + }
> +
> + if (ref_clk == hba->dev_ref_clk_freq)
> + goto out; /* nothing to update */
> +
> + err = ufshcd_query_attr_retry(hba, UPIU_QUERY_OPCODE_WRITE_ATTR,
> + QUERY_ATTR_IDN_REF_CLK_FREQ, 0, 0,
> + &hba->dev_ref_clk_freq);
> +
> + if (err)
> + dev_err(hba->dev, "%s: bRefClkFreq setting to %d Hz failed\n",
> + __func__, ufs_ref_clk_freqs[hba->dev_ref_clk_freq].freq_hz);
> + /*
> + * It is good to print this out here to debug any later failures
> + * related to gear switch.
> + */
> + dev_dbg(hba->dev, "%s: bRefClkFreq setting to %d Hz succeeded\n",
> + __func__, ufs_ref_clk_freqs[hba->dev_ref_clk_freq].freq_hz);
> +
> +out:
> + return err;
> +}
> +
> /**
> * ufshcd_probe_hba - probe hba to detect device and initialize
> * @hba: per-adapter instance
> @@ -6361,6 +6444,12 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
> "%s: Failed getting max supported power mode\n",
> __func__);
> } else {
> + /*
> + * Set the right value to bRefClkFreq before attempting to
> + * switch to HS gears.
> + */
> + if (hba->dev_ref_clk_freq < bREF_CLK_FREQ_INVAL)
hba->dev_ref_clk_freq does not always get initialized
> + ufshcd_set_dev_ref_clk(hba);
> ret = ufshcd_config_pwr_mode(hba, &hba->max_pwr_info.info);
> if (ret) {
> dev_err(hba->dev, "%s: Failed setting power mode, err = %d\n",
> diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
> index 8110dcd..101a75c 100644
> --- a/drivers/scsi/ufs/ufshcd.h
> +++ b/drivers/scsi/ufs/ufshcd.h
> @@ -548,6 +548,7 @@ struct ufs_hba {
> void *priv;
> unsigned int irq;
> bool is_irq_enabled;
> + u32 dev_ref_clk_freq;
>
> /* Interrupt aggregation support is broken */
> #define UFSHCD_QUIRK_BROKEN_INTR_AGGR 0x1
> @@ -746,6 +747,7 @@ static inline void ufshcd_rmwl(struct ufs_hba *hba, u32 mask, u32 val, u32 reg)
> int ufshcd_wait_for_register(struct ufs_hba *hba, u32 reg, u32 mask,
> u32 val, unsigned long interval_us,
> unsigned long timeout_ms, bool can_sleep);
> +void ufshcd_parse_dev_ref_clk_freq(struct ufs_hba *hba);
>
> static inline void check_upiu_size(void)
> {
>
