Re: [PATCH 01/10] Platform/NXP: Library to provide helper functions.

[Leif Lindholm <leif.lindholm@linaro.org>]

On Tue, Nov 07, 2017 at 08:12:07PM +0530, Meenakshi Aggarwal wrote:
> UtilsLib provide helper functions which will be needed
> by NXP SoCs Library and Drivers.
> 
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>
> ---
>  Platform/NXP/Include/Library/Utils.h    | 137 ++++++++++++++++++++++++++++++++
>  Platform/NXP/Library/UtilsLib/Utils.c   |  97 ++++++++++++++++++++++
>  Platform/NXP/Library/UtilsLib/Utils.inf |  30 +++++++
>  3 files changed, 264 insertions(+)
>  create mode 100644 Platform/NXP/Include/Library/Utils.h
>  create mode 100644 Platform/NXP/Library/UtilsLib/Utils.c
>  create mode 100644 Platform/NXP/Library/UtilsLib/Utils.inf
> 
> diff --git a/Platform/NXP/Include/Library/Utils.h b/Platform/NXP/Include/Library/Utils.h
> new file mode 100644
> index 0000000..8920e4d
> --- /dev/null
> +++ b/Platform/NXP/Include/Library/Utils.h
> @@ -0,0 +1,137 @@
> +/** Utils.h
> +  Header defining the General Purpose Utilities
> +
> +  Copyright 2017 NXP
> +
> +  This program and the accompanying materials
> +  are licensed and made available under the terms and conditions of the BSD License
> +  which accompanies this distribution.  The full text of the license may be found at
> +  http://opensource.org/licenses/bsd-license.php
> +
> +  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +
> +**/
> +
> +#ifndef __UTILS_H__
> +#define __UTILS_H__
> +
> +/*
> + * Divide positive or negative dividend by positive divisor and round
> + * to closest UINTNeger. Result is undefined for negative divisors and
> + * for negative dividends if the divisor variable type is unsigned.
> + */
> +#define DIV_ROUND_CLOSEST(X, Divisor)(           \
> +{                                                \
> +  typeof(X) __X = X;                             \
> +  typeof(Divisor) __D = Divisor;                 \
> +  (((typeof(X))-1) > 0 ||                        \
> +    ((typeof(Divisor))-1) > 0 || (__X) > 0) ?    \
> +      (((__X) + ((__D) / 2)) / (__D)) :          \
> +      (((__X) - ((__D) / 2)) / (__D));           \
> +}                                                \
> +)

This function has been lifted verbatim from the Linux kernel, with the
inputs converted to upper case, at a date before commit 4f5901f5a6724
went in. include/linux/kernel.h does not contain an explicit license,
so falls under the Linux kernel default of GPLv2, which is not
compatible with the specified BSD license.

Please have a _very_ _close_ look at any other potential license
infelicities in the code.

> +
> +/*
> + * HammingWeight32: returns the hamming weight (i.e. the number
> + * of bits set) of a 32-bit word
> + */
> +STATIC
> +inline
> +UINTN
> +HammingWeight32 (
> +  IN  UINTN  W
> +  )
> +{
> +  UINTN Res;
> +
> +  Res = (W & 0x55555555) + ((W >> 1) & 0x55555555);
> +  Res = (Res & 0x33333333) + ((Res >> 2) & 0x33333333);
> +  Res = (Res & 0x0F0F0F0F) + ((Res >> 4) & 0x0F0F0F0F);
> +  Res = (Res & 0x00FF00FF) + ((Res >> 8) & 0x00FF00FF);
> +
> +  return (Res & 0x0000FFFF) + ((Res >> 16) & 0x0000FFFF);
> +}

This looks near-identical to an old version from linux lib/hweight.c.

/
    Leif

> +
> +STATIC
> +inline
> +UINTN
> +CpuMaskNext (
> +  IN  UINTN  Cpu,
> +  IN  UINTN  Mask
> +  )
> +{
> +  for (Cpu++; !((1 << Cpu) & Mask); Cpu++)
> +    ;
> +
> +  return Cpu;
> +}
> +
> +#define ForEachCpu(Iter, Cpu, NumCpus, Mask) \
> +  for (Iter = 0, Cpu = CpuMaskNext(-1, Mask); \
> +    Iter < NumCpus; \
> +    Iter++, Cpu = CpuMaskNext(Cpu, Mask)) \
> +
> +/**
> +  Find last (most-significant) bit set
> +
> +  @param   X :        the word to search
> +
> +  Note Fls(0) = 0, Fls(1) = 1, Fls(0x80000000) = 32.
> +
> +**/
> +STATIC
> +inline
> +INT32
> +GenericFls (
> +  IN  INT32  X
> +  )
> +{
> +  INT32 R = 32;
> +
> +  if (!X)
> +    return 0;
> +
> +  if (!(X & 0xffff0000u)) {
> +    X <<= 16;
> +    R -= 16;
> +  }
> +  if (!(X & 0xff000000u)) {
> +    X <<= 8;
> +    R -= 8;
> +  }
> +  if (!(X & 0xf0000000u)) {
> +    X <<= 4;
> +    R -= 4;
> +  }
> +  if (!(X & 0xc0000000u)) {
> +    X <<= 2;
> +    R -= 2;
> +  }
> +  if (!(X & 0x80000000u)) {
> +    X <<= 1;
> +    R -= 1;
> +  }
> +
> +  return R;
> +}

include/asm-generic/bitops/fls.h

/
    Leif

> +
> +/*
> + * PrINT32 Sizes As "Xxx KiB", "Xxx.Y KiB", "Xxx MiB", "Xxx.Y MiB",
> + * Xxx GiB, Xxx.Y GiB, Etc As Needed; Allow for Optional Trailing String
> + * (Like "\n")
> + */
> +VOID
> +PrintSize (
> +  IN  UINT64 Size,
> +  IN  CONST INT8 *S
> +  );
> +
> +/* Function to convert a frequency to MHz */
> +CHAR8 *StringToMHz (
> +  CHAR8   *Buf,
> +  UINT32  Size,
> +  UINT64  Hz
> +  );
> +
> +#endif
> diff --git a/Platform/NXP/Library/UtilsLib/Utils.c b/Platform/NXP/Library/UtilsLib/Utils.c
> new file mode 100644
> index 0000000..4f5a15c
> --- /dev/null
> +++ b/Platform/NXP/Library/UtilsLib/Utils.c
> @@ -0,0 +1,97 @@
> +/** Utils.c
> +
> +  Copyright 2017 NXP
> +
> +  This program and the accompanying materials
> +  are licensed and made available under the terms and conditions of the BSD License
> +  which accompanies this distribution.  The full text of the license may be found at
> +  http://opensource.org/licenses/bsd-license.php
> +
> +  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +
> +**/
> +
> +#include <Library/DebugLib.h>
> +#include <Library/PrintLib.h>
> +#include <Library/Utils.h>
> +
> +/* Function to convert a frequency to MHz */
> +CHAR8 *
> +StringToMHz (
> +  IN  CHAR8   *Buf,
> +  IN  UINT32  Size,
> +  IN  UINT64  Hz
> +  )
> +{
> +  UINT64 L;
> +  UINT64 M;
> +  UINT64 N;
> +
> +  N = DIV_ROUND_CLOSEST(Hz, 1000) / 1000L;
> +  L = AsciiSPrint (Buf, Size, "%ld", N);
> +
> +  Hz -= N * 1000000L;
> +  M = DIV_ROUND_CLOSEST(Hz, 1000L);
> +
> +  if (M != 0) {
> +    AsciiSPrint (Buf + L, Size, ".%03ld", M);
> +  }
> +
> +  return (Buf);
> +}
> +
> +/*
> + * PrINT32 Sizes As "Xxx KiB", "Xxx.Y KiB", "Xxx MiB", "Xxx.Y MiB",
> + * Xxx GiB, Xxx.Y GiB, Etc As Needed; Allow for Optional Trailing String
> + * (Like "\n")
> + */
> +VOID
> +PrintSize (
> +  IN  UINT64 Size,
> +  IN  CONST  INT8 *S
> +  )
> +{
> +  UINT64 M;
> +  UINT64 N;
> +  UINT64 F;
> +  UINT64 D;
> +  CHAR8 C;
> +  UINT32 I;
> +  INT8 Names[6] = {'E', 'P', 'T', 'G', 'M', 'K'};
> +
> +  M = 0;
> +  D = 10 * ARRAY_SIZE(Names);
> +  C = 0;
> +
> +  for (I = 0; I < ARRAY_SIZE(Names); I++, D -= 10) {
> +    if (Size >> D) {
> +      C = Names[I];
> +      break;
> +    }
> +  }
> +
> +  if (!C) {
> +    DEBUG((DEBUG_ERROR, "%Ld Bytes,\n %a", Size, S));
> +    return;
> +  }
> +
> +  N = Size >> D;
> +  F = Size & ((1ULL << D) - 1);
> +
> +  /* if There'S A Remainder, Deal With It */
> +  if (F) {
> +    M = (10ULL * F + (1ULL << (D - 1))) >> D;
> +
> +    if (M >= 10) {
> +           M -= 10;
> +           N += 1;
> +    }
> +  }
> +
> +  DEBUG((DEBUG_ERROR, "%Ld", N));
> +  if (M) {
> +    DEBUG((DEBUG_ERROR, ".%Ld", M));
> +  }
> +  DEBUG((DEBUG_ERROR, " %ciB, %a ", C, S));
> +}
> diff --git a/Platform/NXP/Library/UtilsLib/Utils.inf b/Platform/NXP/Library/UtilsLib/Utils.inf
> new file mode 100644
> index 0000000..9901445
> --- /dev/null
> +++ b/Platform/NXP/Library/UtilsLib/Utils.inf
> @@ -0,0 +1,30 @@
> +#  @Utils.inf
> +
> +#  Copyright 2017 NXP
> +#
> +#  This program and the accompanying materials
> +#  are licensed and made available under the terms and conditions of the BSD License
> +#  which accompanies this distribution.  The full text of the license may be found at
> +#  http://opensource.org/licenses/bsd-license.php
> +#
> +#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> +#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> +#
> +
> +[Defines]
> +  INF_VERSION                    = 0x00010005
> +  BASE_NAME                      = UtilsLib
> +  FILE_GUID                      = 0985d4e8-5a41-40cf-ad12-2ad5d35e817f
> +  MODULE_TYPE                    = BASE
> +  VERSION_STRING                 = 1.0
> +  LIBRARY_CLASS                  = UtilsLib
> +
> +[Packages]
> +  MdePkg/MdePkg.dec
> +  edk2-platforms/Platform/NXP/NxpQoriqLs.dec
> +
> +[LibraryClasses]
> +  PrintLib
> +
> +[Sources.common]
> +  Utils.c
> -- 
> 1.9.1
>