[PATCH V6 3/6] scsi: ufs: qcom: Add multiple frequency support for unipro clk attributes

From: Nitin Rawat
Date: Fri Sep 01 2023 - 07:43:15 EST

Add Support to configure CORE_CLK_1US_CYCLES, PA_VS_CORE_CLK_40NS_CYCLES
for multiple unipro clock frequencies. Currently this is handled only for
only 150Mhz and 75MHz.

Since different qualcomm targets support different unipro frequency, add
support to handle all other frequencies like 403MHz, 300MHz, 202MHz,
150 MHz, 75Mhz, 37.5 MHz.

Co-developed-by: Naveen Kumar Goud Arepalli <quic_narepall@xxxxxxxxxxx>
Signed-off-by: Naveen Kumar Goud Arepalli <quic_narepall@xxxxxxxxxxx>
Signed-off-by: Nitin Rawat <quic_nitirawa@xxxxxxxxxxx>
---
drivers/ufs/host/ufs-qcom.c | 96 ++++++++++++++++++++++++++++---------
drivers/ufs/host/ufs-qcom.h | 10 ++++
2 files changed, 84 insertions(+), 22 deletions(-)

diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index 018e391c276e..e3648e936498 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -94,8 +94,7 @@ static struct ufs_qcom_host *ufs_qcom_hosts[MAX_UFS_QCOM_HOSTS];

static void ufs_qcom_get_default_testbus_cfg(struct ufs_qcom_host *host);
static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba,
- u32 clk_cycles,
- u32 clk_40ns_cycles);
+ bool is_max_freq);

static struct ufs_qcom_host *rcdev_to_ufs_host(struct reset_controller_dev *rcd)
{
@@ -686,13 +685,14 @@ static int ufs_qcom_link_startup_notify(struct ufs_hba *hba,
return -EINVAL;
}

- if (ufs_qcom_cap_qunipro(host))
- /*
- * set unipro core clock cycles to 150 & clear clock
- * divider
- */
- err = ufs_qcom_set_core_clk_ctrl(hba,
- 150, 6);
+ if (ufs_qcom_cap_qunipro(host)) {
+ err = ufs_qcom_set_core_clk_ctrl(hba, true);
+ if (err) {
+ dev_err(hba->dev,
+ "%s cfg core clk ctrl failed\n",
+ __func__);
+ }
+ }

/*
* Some UFS devices (and may be host) have issues if LCC is
@@ -1297,13 +1297,67 @@ static void ufs_qcom_exit(struct ufs_hba *hba)
phy_exit(host->generic_phy);
}
static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba,
- u32 cycles_in_1us,
- u32 cycles_in_40ns)
+ bool is_max_freq)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+ struct list_head *head = &hba->clk_list_head;
u32 core_clk_ctrl_reg, reg;
+ struct ufs_clk_info *clki;
+ u32 cycles_in_1us, cycles_in_40ns;
int ret;

+ list_for_each_entry(clki, head, list) {
+ if (!IS_ERR_OR_NULL(clki->clk) &&
+ !strcmp(clki->name, "core_clk_unipro")) {
+ if (is_max_freq)
+ cycles_in_1us = clki->max_freq;
+ else
+ cycles_in_1us = clk_get_rate(clki->clk);
+ break;
+ }
+ }
+
+ if ((cycles_in_1us % (1000 * 1000)) != 0)
+ cycles_in_1us = cycles_in_1us/(1000 * 1000) + 1;
+ else
+ cycles_in_1us = cycles_in_1us/(1000 * 1000);
+
+ /*
+ * Generic formulae for cycles_in_40ns = (freq_unipro/25) is not
+ * applicable for all frequencies. For ex: ceil(37.5 MHz/25) will
+ * be 2 and ceil(403 MHZ/25) will be 17 whereas Hardware
+ * specification expect to be 16. Hence use exact hardware spec
+ * mandated value for cycles_in_40ns instead of calculating using
+ * generic formulae.
+ */
+ switch (cycles_in_1us) {
+ case UNIPRO_CORE_CLK_FREQ_403_MHZ:
+ cycles_in_40ns = 16;
+ break;
+ case UNIPRO_CORE_CLK_FREQ_300_MHZ:
+ cycles_in_40ns = 12;
+ break;
+ case UNIPRO_CORE_CLK_FREQ_201_5_MHZ:
+ cycles_in_40ns = 8;
+ break;
+ case UNIPRO_CORE_CLK_FREQ_150_MHZ:
+ cycles_in_40ns = 6;
+ break;
+ case UNIPRO_CORE_CLK_FREQ_100_MHZ:
+ cycles_in_40ns = 4;
+ break;
+ case UNIPRO_CORE_CLK_FREQ_75_MHZ:
+ cycles_in_40ns = 3;
+ break;
+ case UNIPRO_CORE_CLK_FREQ_37_5_MHZ:
+ cycles_in_40ns = 2;
+ break;
+ default:
+ ret = -EINVAL;
+ dev_err(hba->dev, "UNIPRO clk freq %u MHz not supported\n",
+ cycles_in_1us);
+ }
+
ret = ufshcd_dme_get(hba,
UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
&core_clk_ctrl_reg);
@@ -1326,7 +1380,7 @@ static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba,
/* Clear CORE_CLK_DIV_EN */
core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT;

- err = ufshcd_dme_set(hba,
+ ret = ufshcd_dme_set(hba,
UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
core_clk_ctrl_reg);
/*
@@ -1334,25 +1388,25 @@ static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba,
* PA_VS_CORE_CLK_40NS_CYCLES attribute per programmed
* frequency of unipro core clk of UFS host controller.
*/
- if (!err && (host->hw_ver.major >= 4)) {
+ if (!ret && (host->hw_ver.major >= 4)) {
if (cycles_in_40ns > PA_VS_CORE_CLK_40NS_CYCLES_MASK)
return -EINVAL;

- err = ufshcd_dme_get(hba,
+ ret = ufshcd_dme_get(hba,
UIC_ARG_MIB(PA_VS_CORE_CLK_40NS_CYCLES),
&reg);
- if (err)
- return err;
+ if (ret)
+ return ret;

reg &= ~PA_VS_CORE_CLK_40NS_CYCLES_MASK;
reg |= cycles_in_40ns;

- err = ufshcd_dme_set(hba,
+ ret = ufshcd_dme_set(hba,
UIC_ARG_MIB(PA_VS_CORE_CLK_40NS_CYCLES),
reg);
}

- return err;
+ return ret;
}

static int ufs_qcom_clk_scale_up_pre_change(struct ufs_hba *hba)
@@ -1368,8 +1422,7 @@ static int ufs_qcom_clk_scale_up_post_change(struct ufs_hba *hba)
if (!ufs_qcom_cap_qunipro(host))
return 0;

- /* set unipro core clock cycles to 150 and clear clock divider */
- return ufs_qcom_set_core_clk_ctrl(hba, 150, 6);
+ return ufs_qcom_set_core_clk_ctrl(hba, true);
}

static int ufs_qcom_clk_scale_down_pre_change(struct ufs_hba *hba)
@@ -1404,8 +1457,7 @@ static int ufs_qcom_clk_scale_down_post_change(struct ufs_hba *hba)
if (!ufs_qcom_cap_qunipro(host))
return 0;

- /* set unipro core clock cycles to 75 and clear clock divider */
- return ufs_qcom_set_core_clk_ctrl(hba, 75, 3);
+ return ufs_qcom_set_core_clk_ctrl(hba, false);
}

static int ufs_qcom_clk_scale_notify(struct ufs_hba *hba,
diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h
index d81bf1a1b77a..bc176ef58e3e 100644
--- a/drivers/ufs/host/ufs-qcom.h
+++ b/drivers/ufs/host/ufs-qcom.h
@@ -9,6 +9,7 @@
#include <linux/reset.h>
#include <soc/qcom/ice.h>
#include <ufs/ufshcd.h>
+#include <linux/math.h>

#define MAX_UFS_QCOM_HOSTS 1
#define MAX_U32 (~(u32)0)
@@ -79,6 +80,15 @@ enum {
UFS_MEM_CQIS_VS = 0x8,
};

+/* QCOM UFS host controller core clk frequencies */
+#define UNIPRO_CORE_CLK_FREQ_37_5_MHZ 38
+#define UNIPRO_CORE_CLK_FREQ_75_MHZ 75
+#define UNIPRO_CORE_CLK_FREQ_100_MHZ 100
+#define UNIPRO_CORE_CLK_FREQ_150_MHZ 150
+#define UNIPRO_CORE_CLK_FREQ_300_MHZ 300
+#define UNIPRO_CORE_CLK_FREQ_201_5_MHZ 202
+#define UNIPRO_CORE_CLK_FREQ_403_MHZ 403
+
#define UFS_CNTLR_2_x_x_VEN_REGS_OFFSET(x) (0x000 + x)
#define UFS_CNTLR_3_x_x_VEN_REGS_OFFSET(x) (0x400 + x)

--
2.17.1