On Tuesday 05 February 2013 08:59 PM, Nishanth Menon wrote:
[..]

    Answering all of your above questions here.
    The above data is for OMAP4 and not OMAP5. This file was modified
    here just to include dummy dividers. Because we were now using a
    common dpll_params structure, there was no functional change in this
    file. I think the problem was commit log was missing this info.
     I will update to clarify this.
I dont think updating commit log alone is the right solution -> renaming the
variables make more sense - making ones meant for OMAP4 as _omap4430, 60
etc help readability of code.
 omap4/hw_data.c has separate arrays to represent 4430, 4460 dplls data.

[...]
  /* ABE M & N values with 32K clock as source */
  static const struct dpll_params abe_dpll_params_32k_196608khz = {
We do not intend to support 32K ABE source except when doing DPLL
cascading - so this is in effect an configuration which is
un-used in any s/w line.

   1) In fact we not locking ABE, IVA, USB DPLLs any more in bootloader
      unless some one enable a CLOCKS_ENABLE_ALL config.
      But we still have there data, so that we can quickly experiment
      when needed.
it is no longer supported on OMAP5. If you have doubts on the silicon
usecase specification, I recommend you do read the TI internal
documentation for the same.
 >>
   2) I remember that locking with 32K source was considered better
      because, we can cut sys_clk when audio is still running.
      Also i think that the jitter was not a real problem for audio
      even when running with 32Khz clock. I have to check this point
      again.
please check again.

  I even checked the latest version of ES2.0 TRM.
  M, N specified are 750, 0. So these are ones used to lock at 32KHZ.

      The reason we had both the sources supported was just from an
      experiment motive. I have seen that during pre silicon, we have
As a rule, experimentation code should NOT be in mainline. only
recommended operation code should ever be put in mainline - real
products are supposed to ramp with this code.

  Yes, by default we have set it to OPP_NOM.
  There where many situations where there was a need to boot with
  higher OPPs for performance measurements with mainline.
  So it was better to change just one variable than to add the full
  data for that OPP in those cases. This has helped many times in the
  past.

      to switch the clock source from default to get locking. So having
      support for both helps in those cases.
not if the silicon is neither validated NOR expected to be supported at
this.
[...]
  static const struct dpll_params mpu_dpll_params_1_5ghz[NUM_SYS_CLKS] = {
I am not sure we'd like to do this.
     This file is common for ES1.0 as well. Also i have added frequency
     tables for OPP_HIGH and OPP_LOW as well. We some times find it
     nessecary to boot with a different than OPP_NOM to do experiments.
     So this is useful from that point.  But what is missing is the VDDs
     which I usually add manually while testing. But now to complete
    this, i will add that as well.
Why? Es1.0 will never be publically released, it never was meant to be
public. ES2.0 is the only one meant to go out. Supporting ES1.0 and
ES2.0 means a ton of redundant code being maintained in mainline with no
product lines meant to actively using it - ever! Do we really want to do
this??

 Ok, i will clean up ES1.0 data in a separate patch series after this.

-       {125, 0, 1, -1, -1, -1, -1, -1, -1, -1},        /* 12 MHz   */
-       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 13 MHz   */
-       {625, 6, 1, -1, -1, -1, -1, -1, -1, -1},        /* 16.8 MHz */
-       {625, 7, 1, -1, -1, -1, -1, -1, -1, -1},        /* 19.2 MHz */
-       {750, 12, 1, -1, -1, -1, -1, -1, -1, -1},       /* 26 MHz   */
-       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 27 MHz   */
-       {625, 15, 1, -1, -1, -1, -1, -1, -1, -1}        /* 38.4 MHz */
+       {125, 0, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},        /* 12 MHz   */
+       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 13 MHz   */
+       {625, 6, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},        /* 16.8 MHz */
+       {625, 7, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},        /* 19.2 MHz */
+       {750, 12, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 26 MHz   */
+       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 27 MHz   */
+       {625, 15, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1}        /* 38.4 MHz */
  };

  static const struct dpll_params mpu_dpll_params_2ghz[NUM_SYS_CLKS] = {
again, frequency is wrong for es2.0?
    This file is common for ES1.0 as well.
ES1.0 DOES NOT run at 2GHz!

 Ok, i will clean up ES1.0 data separately.

-       {500, 2, 1, -1, -1, -1, -1, -1, -1, -1},        /* 12 MHz   */
-       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 13 MHz   */
-       {2024, 16, 1, -1, -1, -1, -1, -1, -1, -1},      /* 16.8 MHz */
-       {625, 5, 1, -1, -1, -1, -1, -1, -1, -1},        /* 19.2 MHz */
-       {1000, 12, 1, -1, -1, -1, -1, -1, -1, -1},      /* 26 MHz   */
-       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 27 MHz   */
-       {625, 11, 1, -1, -1, -1, -1, -1, -1, -1}        /* 38.4 MHz */
+       {500, 2, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},        /* 12 MHz   */
+       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 13 MHz   */
+       {2024, 16, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},      /* 16.8 MHz */
+       {625, 5, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},        /* 19.2 MHz */
+       {1000, 12, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1},      /* 26 MHz   */
+       {-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1},       /* 27 MHz   */
+       {625, 11, 1, -1, -1, -1, -1, -1, -1, -1, -1, -1}        /* 38.4 MHz */
  };

  static const struct dpll_params mpu_dpll_params_1100mhz[NUM_SYS_CLKS] = {
again, frequency is wrong for es2.0?
    MPU runs at 1100 MHZ in OPP_NOM on 2.0
1099MHz - I suggest latest spec to be clear on this - i suggest
reviewing further based on update.
 MPU runs at 1099.9 MHZ

[...]
+       .iva = iva_dpll_params_2330mhz_es2,
+#ifdef CONFIG_SYS_OMAP_ABE_SYSCK
+       .abe = abe_dpll_params_sysclk_196608khz,
+#else
+       .abe = &abe_dpll_params_32k_196608khz,
+#endif
I strongly suggest dumping ABE sourcing from 32K clock - the code is
just a nuisance waiting to exercise an unsupported silicon feature
waiting to happen.
[...]
        default:
diff --git a/arch/arm/include/asm/arch-omap5/clocks.h 
b/arch/arm/include/asm/arch-omap5/clocks.h
index 15362ae..685aad5 100644
--- a/arch/arm/include/asm/arch-omap5/clocks.h
+++ b/arch/arm/include/asm/arch-omap5/clocks.h
@@ -208,6 +208,10 @@
  #define VDD_MM_5432   1150
  #define VDD_CORE_5432 1150

+#define VDD_MPU_ES2    1060
+#define VDD_MM_ES2     1025
+#define VDD_CORE_ES2   1040
^^^ these are meant only for OPP_NOM - considering that you have DPLLs
for OPP_SB added in, do you even expect these devices to bootup at
anything *but* OPP_NOM??
   I agree. I add it manually while doing experiments. I will add these
   here.
As a rule we want maintainable s/w in mainline, not experimental code.
maintainable s/w implies s/w that adheres to SoC's specified operational
ranges unfortunately :(.


Regards,
 Sricharan


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