On Wed, Dec 05, 2018 at 02:51:07PM +0800, Joseph Lo wrote:

On 12/5/18 2:20 PM, Joseph Lo wrote:

quoted

On 12/4/18 11:46 PM, Peter De Schrijver wrote:

quoted

On Tue, Dec 04, 2018 at 05:25:37PM +0800, Joseph Lo wrote:

quoted

When generating the OPP table, the voltages are round down with the
alignment from the regulator. The alignment should be applied for
voltages look up as well.

Based on the work of Penny Chiu [off-list ref].

Signed-off-by: Joseph Lo <redacted>
---
  drivers/clk/tegra/clk-dfll.c | 26 +++++++++++++++-----------
  1 file changed, 15 insertions(+), 11 deletions(-)

diff --git a/drivers/clk/tegra/clk-dfll.c b/drivers/clk/tegra/clk-dfll.c
index c294a2989f31..4a943c136d4d 100644
--- a/drivers/clk/tegra/clk-dfll.c
+++ b/drivers/clk/tegra/clk-dfll.c

@@ -804,17 +804,17 @@ static void dfll_init_out_if(struct

tegra_dfll *td)
  static int find_lut_index_for_rate(struct tegra_dfll *td,
unsigned long rate)
  {
      struct dev_pm_opp *opp;
-    int i, uv;
+    int i, align_volt;
      opp = dev_pm_opp_find_freq_ceil(td->soc->dev, &rate);
      if (IS_ERR(opp))
          return PTR_ERR(opp);
-    uv = dev_pm_opp_get_voltage(opp);
+    align_volt = dev_pm_opp_get_voltage(opp) /
td->soc->alignment.step_uv;
      dev_pm_opp_put(opp);
      for (i = td->lut_bottom; i < td->lut_size; i++) {
-        if (regulator_list_voltage(td->vdd_reg, td->lut[i]) == uv)
+        if ((td->lut_uv[i] / td->soc->alignment.step_uv) >= align_volt)
              return i;
      }

@@ -1532,15 +1532,17 @@ static int dfll_init(struct tegra_dfll *td)

   */

These 2 functions are only valid for I2C mode. We should probably add a
WARN_ON() in case they are called when PWM mode is used and return
-EINVAL.

Okay, will add that.

Peter,

Sorry, just double check again. These 2 functions are used for generating
LUT table for DFLL-I2C mode. They are only used in "dfll_build_i2c_lut"
function. So I think it's fine. The WARN_ON for protection from PWM mode is
not necessary.

They are indeed not used today, but to prevent them from being used in
the future I was thinking it makes sense to add some form of protection
here.

Peter.

quoted

quoted

quoted

  static int find_vdd_map_entry_exact(struct tegra_dfll *td, int uV)
  {
-    int i, n_voltages, reg_uV;
+    int i, n_voltages, reg_volt, align_volt;
+    align_volt = uV / td->soc->alignment.step_uv;
      n_voltages = regulator_count_voltages(td->vdd_reg);
      for (i = 0; i < n_voltages; i++) {
-        reg_uV = regulator_list_voltage(td->vdd_reg, i);
-        if (reg_uV < 0)
+        reg_volt = regulator_list_voltage(td->vdd_reg, i) /
+                td->soc->alignment.step_uv;
+        if (reg_volt < 0)
              break;
-        if (uV == reg_uV)
+        if (align_volt == reg_volt)
              return i;
      }

@@ -1554,15 +1556,17 @@ static int

find_vdd_map_entry_exact(struct tegra_dfll *td, int uV)
   * */
  static int find_vdd_map_entry_min(struct tegra_dfll *td, int uV)
  {
-    int i, n_voltages, reg_uV;
+    int i, n_voltages, reg_volt, align_volt;
+    align_volt = uV / td->soc->alignment.step_uv;
      n_voltages = regulator_count_voltages(td->vdd_reg);
      for (i = 0; i < n_voltages; i++) {
-        reg_uV = regulator_list_voltage(td->vdd_reg, i);
-        if (reg_uV < 0)
+        reg_volt = regulator_list_voltage(td->vdd_reg, i) /
+                td->soc->alignment.step_uv;
+        if (reg_volt < 0)
              break;
-        if (uV <= reg_uV)
+        if (align_volt <= reg_volt)
              return i;
      }
-- 
2.19.2

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