[PATCH V4] scsi: ufs: qcom: Align programming sequence as per HW spec

From: Nitin Rawat
Date: Mon Aug 14 2023 - 10:30:47 EST

Align clock configuration as per Qualcomm UFS controller hardware
specification. As part of this patch we are aligning sequence
for SYS1CLK_1US, MAX_CORE_CLK_1US_CYCLES and
PA_VS_CORE_CLK_40NS_CYCLES.

SYS1CLK_1US_REG represents the required number of system 1-clock
cycles for one microsecond. MAX_CORE_CLK_1US_CYCLES represents the
required number of Qunipro core clock for one microsecond.
PA_VS_CORE_CLK_40NS_CYCLES represents the required number of
Qunipro core clock for 40 nanoseconds.

a) Support CORE_CLK_1US_CYCLES and PA_VS_CORE_CLK_40NS_CYCLES
for multiple unipro clock frequencies. This is currently handled
only for only 150Mhz and 75MHz. Also Configure SYS1CLK_1US_REG for
pre scale up condition.

b) Update offset for core_clk_1us_cycles in DME_VS_CORE_CLK_CTRL. This
offset is changed from Qualcomm UFS Controller V4.0.0 onwards.

c) Qualcomm UFS controller V4.0 and onwards PA_VS_CORE_CLK_40NS_CYCLES
attribute needs to be programmed with frequency of unipro core clk of
UFS host controller.

d) Enable internal HW division of unipro core_clk based on scale up and
scale down condition. This bit should be cleared before entering any
SVS mode.

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>
---

Changes from v3:
-Addressed bjorn comment to update commit msg to capture change details.

Changes from v2:
- Addressed bao comment, removed duplicate clock timer cfg API call

Changes from v1:
- Addressed bao comment, removed wrapper function
- Tab alignment
---
drivers/ufs/host/ufs-qcom.c | 261 ++++++++++++++++++++++++++----------
drivers/ufs/host/ufs-qcom.h | 20 ++-
2 files changed, 207 insertions(+), 74 deletions(-)

diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index f88febb23123..5b603886f3d1 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -91,10 +91,7 @@ static const struct __ufs_qcom_bw_table {
};

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_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
- u32 clk_cycles);

static struct ufs_qcom_host *rcdev_to_ufs_host(struct reset_controller_dev *rcd)
{
@@ -532,7 +529,8 @@ static int ufs_qcom_hce_enable_notify(struct ufs_hba *hba,
* Return: zero for success and non-zero in case of a failure.
*/
static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
- u32 hs, u32 rate, bool update_link_startup_timer)
+ u32 hs, u32 rate, bool link_startup,
+ bool is_pre_scale_up)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
struct ufs_clk_info *clki;
@@ -563,11 +561,16 @@ static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
/*
* The Qunipro controller does not use following registers:
* SYS1CLK_1US_REG, TX_SYMBOL_CLK_1US_REG, CLK_NS_REG &
- * UFS_REG_PA_LINK_STARTUP_TIMER
- * But UTP controller uses SYS1CLK_1US_REG register for Interrupt
- * Aggregation logic.
- */
- if (ufs_qcom_cap_qunipro(host) && !ufshcd_is_intr_aggr_allowed(hba))
+ * UFS_REG_PA_LINK_STARTUP_TIMER.
+ * However UTP controller uses SYS1CLK_1US_REG register for Interrupt
+ * Aggregation logic and Auto hibern8 logic.
+ * It is mandatory to write SYS1CLK_1US_REG register on UFS host
+ * controller V4.0.0 onwards.
+ */
+ if (ufs_qcom_cap_qunipro(host) &&
+ !(ufshcd_is_intr_aggr_allowed(hba) ||
+ ufshcd_is_auto_hibern8_supported(hba) ||
+ host->hw_ver.major >= 4))
return 0;

if (gear == 0) {
@@ -576,8 +579,14 @@ static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
}

list_for_each_entry(clki, &hba->clk_list_head, list) {
- if (!strcmp(clki->name, "core_clk"))
- core_clk_rate = clk_get_rate(clki->clk);
+ if (!strcmp(clki->name, "core_clk")) {
+ if (is_pre_scale_up)
+ core_clk_rate = clki->max_freq;
+ else
+ core_clk_rate = clk_get_rate(clki->clk);
+ break;
+ }
+
}

/* If frequency is smaller than 1MHz, set to 1MHz */
@@ -657,7 +666,7 @@ static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
mb();
}

- if (update_link_startup_timer && host->hw_ver.major != 0x5) {
+ if (link_startup && host->hw_ver.major != 0x5) {
ufshcd_writel(hba, ((core_clk_rate / MSEC_PER_SEC) * 100),
REG_UFS_CFG0);
/*
@@ -670,6 +679,105 @@ static int ufs_qcom_cfg_timers(struct ufs_hba *hba, u32 gear,
return 0;
}

+static int ufs_qcom_set_core_clk_ctrl(struct ufs_hba *hba,
+ u32 clk_1us_cycles,
+ u32 clk_40ns_cycles,
+ bool scale_up)
+{
+ struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+ u32 mask = MAX_CORE_CLK_1US_CYCLES_MASK;
+ u32 offset = 0;
+ u32 reg;
+ int err;
+
+ /* Bit mask and offset changed on UFS host controller V4.0.0 onwards */
+ if (host->hw_ver.major >= 4) {
+ mask = MAX_CORE_CLK_1US_CYCLES_MASK_V4;
+ offset = MAX_CORE_CLK_1US_CYCLES_OFFSET_V4;
+ }
+
+ if (clk_1us_cycles > mask)
+ return -EINVAL;
+
+ err = ufshcd_dme_get(hba, UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL), &reg);
+ if (err)
+ return err;
+
+ reg &= ~(mask << offset);
+ reg |= clk_1us_cycles << offset;
+
+ if (scale_up)
+ reg |= CORE_CLK_DIV_EN_BIT;
+
+ err = ufshcd_dme_set(hba, UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL), reg);
+ if (err)
+ return err;
+
+ /*
+ * UFS host controller V4.0.0 onwards needs to program
+ * PA_VS_CORE_CLK_40NS_CYCLES attribute per programmed
+ * frequency of unipro core clk of UFS host controller.
+ */
+ if (host->hw_ver.major >= 4) {
+ if (clk_40ns_cycles > PA_VS_CORE_CLK_40NS_CYCLES_MASK)
+ return -EINVAL;
+
+ err = ufshcd_dme_get(hba,
+ UIC_ARG_MIB(PA_VS_CORE_CLK_40NS_CYCLES),
+ &reg);
+ if (err)
+ return err;
+
+ reg &= ~PA_VS_CORE_CLK_40NS_CYCLES_MASK;
+ reg |= clk_40ns_cycles;
+
+ err = ufshcd_dme_set(hba,
+ UIC_ARG_MIB(PA_VS_CORE_CLK_40NS_CYCLES),
+ reg);
+ }
+
+ return err;
+}
+
+static int ufs_qcom_cfg_core_clk_ctrl(struct ufs_hba *hba)
+{
+ struct list_head *head = &hba->clk_list_head;
+ struct ufs_clk_info *clki;
+ u32 max_freq = 0;
+ int err;
+
+ list_for_each_entry(clki, head, list) {
+ if (!IS_ERR_OR_NULL(clki->clk) &&
+ (!strcmp(clki->name, "core_clk_unipro"))) {
+ max_freq = clki->max_freq;
+ break;
+ }
+ }
+
+ switch (max_freq) {
+ case MHZ_403:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 403, 16, true);
+ break;
+ case MHZ_300:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 300, 12, true);
+ break;
+ case MHZ_201_5:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 202, 8, true);
+ break;
+ case MHZ_150:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 150, 6, true);
+ break;
+ case MHZ_100:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 100, 4, true);
+ break;
+ default:
+ dev_err(hba->dev, "unipro max_freq=%u entry missing\n", max_freq);
+ err = -EINVAL;
+ break;
+ }
+
+ return err;
+}
static int ufs_qcom_link_startup_notify(struct ufs_hba *hba,
enum ufs_notify_change_status status)
{
@@ -679,19 +787,21 @@ static int ufs_qcom_link_startup_notify(struct ufs_hba *hba,
switch (status) {
case PRE_CHANGE:
if (ufs_qcom_cfg_timers(hba, UFS_PWM_G1, SLOWAUTO_MODE,
- 0, true)) {
+ 0, true, false)) {
dev_err(hba->dev, "%s: ufs_qcom_cfg_timers() failed\n",
__func__);
return -EINVAL;
}

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

/*
* Some UFS devices (and may be host) have issues if LCC is
@@ -926,7 +1036,7 @@ static int ufs_qcom_pwr_change_notify(struct ufs_hba *hba,
case POST_CHANGE:
if (ufs_qcom_cfg_timers(hba, dev_req_params->gear_rx,
dev_req_params->pwr_rx,
- dev_req_params->hs_rate, false)) {
+ dev_req_params->hs_rate, false, false)) {
dev_err(hba->dev, "%s: ufs_qcom_cfg_timers() failed\n",
__func__);
/*
@@ -1296,69 +1406,52 @@ static void ufs_qcom_exit(struct ufs_hba *hba)
phy_exit(host->generic_phy);
}

-static int ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(struct ufs_hba *hba,
- u32 clk_cycles)
+static int ufs_qcom_clk_scale_up_pre_change(struct ufs_hba *hba)
{
- int err;
- u32 core_clk_ctrl_reg;
-
- if (clk_cycles > DME_VS_CORE_CLK_CTRL_MAX_CORE_CLK_1US_CYCLES_MASK)
- return -EINVAL;
-
- err = ufshcd_dme_get(hba,
- UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
- &core_clk_ctrl_reg);
- 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;
-
- /* Clear CORE_CLK_DIV_EN */
- core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT;
+ struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+ struct ufs_pa_layer_attr *attr = &host->dev_req_params;
+ int err = 0;

- return ufshcd_dme_set(hba,
- UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
- core_clk_ctrl_reg);
-}
+ if (!ufs_qcom_cap_qunipro(host))
+ goto out;

-static int ufs_qcom_clk_scale_up_pre_change(struct ufs_hba *hba)
-{
- /* nothing to do as of now */
- return 0;
+ if (attr) {
+ err = ufs_qcom_cfg_timers(hba, attr->gear_rx,
+ attr->pwr_rx, attr->hs_rate,
+ false, true);
+ if (err)
+ dev_err(hba->dev, "%s ufs cfg timer failed\n",
+ __func__);
+ }
+ err = ufs_qcom_cfg_core_clk_ctrl(hba);
+out:
+ return err;
}

static int ufs_qcom_clk_scale_up_post_change(struct ufs_hba *hba)
{
- struct ufs_qcom_host *host = ufshcd_get_variant(hba);
-
- if (!ufs_qcom_cap_qunipro(host))
- return 0;
-
- /* set unipro core clock cycles to 150 and clear clock divider */
- return ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(hba, 150);
+ return 0;
}

static int ufs_qcom_clk_scale_down_pre_change(struct ufs_hba *hba)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
int err;
- u32 core_clk_ctrl_reg;
+ u32 reg;

if (!ufs_qcom_cap_qunipro(host))
return 0;

- err = ufshcd_dme_get(hba,
- UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
- &core_clk_ctrl_reg);
+ err = ufshcd_dme_get(hba, UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL), &reg);
+ if (err)
+ return err;

/* make sure CORE_CLK_DIV_EN is cleared */
- if (!err &&
- (core_clk_ctrl_reg & DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT)) {
- core_clk_ctrl_reg &= ~DME_VS_CORE_CLK_CTRL_CORE_CLK_DIV_EN_BIT;
+ if (reg & CORE_CLK_DIV_EN_BIT) {
+ reg &= ~CORE_CLK_DIV_EN_BIT;
err = ufshcd_dme_set(hba,
UIC_ARG_MIB(DME_VS_CORE_CLK_CTRL),
- core_clk_ctrl_reg);
+ reg);
}

return err;
@@ -1367,19 +1460,50 @@ static int ufs_qcom_clk_scale_down_pre_change(struct ufs_hba *hba)
static int ufs_qcom_clk_scale_down_post_change(struct ufs_hba *hba)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+ struct ufs_pa_layer_attr *attr = &host->dev_req_params;
+ struct list_head *head = &hba->clk_list_head;
+ struct ufs_clk_info *clki;
+ u32 curr_freq = 0;
+ int err;

if (!ufs_qcom_cap_qunipro(host))
return 0;

- /* set unipro core clock cycles to 75 and clear clock divider */
- return ufs_qcom_set_dme_vs_core_clk_ctrl_clear_div(hba, 75);
+ if (attr)
+ ufs_qcom_cfg_timers(hba, attr->gear_rx, attr->pwr_rx,
+ attr->hs_rate, false, false);
+
+ list_for_each_entry(clki, head, list) {
+ if (!IS_ERR_OR_NULL(clki->clk) &&
+ (!strcmp(clki->name, "core_clk_unipro"))) {
+ curr_freq = clk_get_rate(clki->clk);
+ break;
+ }
+ }
+
+ switch (curr_freq) {
+ case MHZ_37_5:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 38, 2, false);
+ break;
+ case MHZ_75:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 75, 3, false);
+ break;
+ case MHZ_100:
+ err = ufs_qcom_set_core_clk_ctrl(hba, 100, 4, false);
+ break;
+ default:
+ err = -EINVAL;
+ dev_err(hba->dev, "unipro curr_freq=%u entry missing\n", curr_freq);
+ break;
+ }
+
+ return err;
}

static int ufs_qcom_clk_scale_notify(struct ufs_hba *hba,
bool scale_up, enum ufs_notify_change_status status)
{
struct ufs_qcom_host *host = ufshcd_get_variant(hba);
- struct ufs_pa_layer_attr *dev_req_params = &host->dev_req_params;
int err = 0;

/* check the host controller state before sending hibern8 cmd */
@@ -1409,11 +1533,6 @@ static int ufs_qcom_clk_scale_notify(struct ufs_hba *hba,
return err;
}

- ufs_qcom_cfg_timers(hba,
- dev_req_params->gear_rx,
- dev_req_params->pwr_rx,
- dev_req_params->hs_rate,
- false);
ufs_qcom_icc_update_bw(host);
ufshcd_uic_hibern8_exit(hba);
}
diff --git a/drivers/ufs/host/ufs-qcom.h b/drivers/ufs/host/ufs-qcom.h
index d6f8e74bd538..d10234f6280b 100644
--- a/drivers/ufs/host/ufs-qcom.h
+++ b/drivers/ufs/host/ufs-qcom.h
@@ -79,6 +79,17 @@ enum {
UFS_MEM_CQIS_VS = 0x8,
};

+
+/* QCOM UFS host controller core clk frequencies */
+#define MHZ_37_5 37500000
+#define MHZ_50 50000000
+#define MHZ_75 75000000
+#define MHZ_100 100000000
+#define MHZ_150 150000000
+#define MHZ_300 300000000
+#define MHZ_201_5 201500000
+#define MHZ_403 403000000
+
#define UFS_CNTLR_2_x_x_VEN_REGS_OFFSET(x) (0x000 + x)
#define UFS_CNTLR_3_x_x_VEN_REGS_OFFSET(x) (0x400 + x)

@@ -129,9 +140,12 @@ 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 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
-
+#define MAX_CORE_CLK_1US_CYCLES_MASK_V4 0xFFF
+#define MAX_CORE_CLK_1US_CYCLES_OFFSET_V4 0x10
+#define MAX_CORE_CLK_1US_CYCLES_MASK 0xFF
+#define CORE_CLK_DIV_EN_BIT BIT(8)
+#define PA_VS_CORE_CLK_40NS_CYCLES 0x9007
+#define PA_VS_CORE_CLK_40NS_CYCLES_MASK 0x3F
static inline void
ufs_qcom_get_controller_revision(struct ufs_hba *hba,
u8 *major, u16 *minor, u16 *step)
--
2.17.1