[Midnightbsd-cvs] [MidnightBSD/src] 3c5232: Disable new clang 10.0.0 warnings about converting...

[Lucas Holt]

  Branch: refs/heads/master
  Home:   https://github.com/MidnightBSD/src
  Commit: 3c5232206f77ab1122653f15f9f04cb316ade55e
      https://github.com/MidnightBSD/src/commit/3c5232206f77ab1122653f15f9f04cb316ade55e
  Author: Lucas Holt <luke at foolishgames.com>
  Date:   2020-11-14 (Sat, 14 Nov 2020)

  Changed paths:
    M sys/dev/tpm/tpm_crb.c

  Log Message:
  -----------
  Disable new clang 10.0.0 warnings about converting the result of shift
operations to a boolean in tpm(4):

sys/dev/tpm/tpm_crb.c:301:32: error: converting the result of '<<' to a boolean; did you mean '(1 << (0)) != 0'? [-Werror,-Wint-in-bool-context]
        WR4(sc, TPM_CRB_CTRL_CANCEL, !TPM_CRB_CTRL_CANCEL_CMD);
                                      ^
sys/dev/tpm/tpm_crb.c:73:34: note: expanded from macro 'TPM_CRB_CTRL_CANCEL_CMD'
                                        ^
sys/dev/tpm/tpm20.h:60:19: note: expanded from macro 'BIT'
                  ^

Such warnings can be useful in C++ contexts, but not so much in kernel
drivers, where this type of bit twiddling is commonplace.  So disable it
for this case.

MFC r357366:

Revert r357349, since the clang 10.0.0 warning was actually correct, and
the ! operator should have been a ~ instead:

  Merge r357348 from the clang 10.0.0 import branch:

  Disable new clang 10.0.0 warnings about converting the result of
  shift operations to a boolean in tpm(4):

  sys/dev/tpm/tpm_crb.c:301:32: error: converting the result of '<<' to a boolean; did you mean '(1 << (0)) != 0'? [-Werror,-Wint-in-bool-context]
	  WR4(sc, TPM_CRB_CTRL_CANCEL, !TPM_CRB_CTRL_CANCEL_CMD);
					^
  sys/dev/tpm/tpm_crb.c:73:34: note: expanded from macro 'TPM_CRB_CTRL_CANCEL_CMD'
  #define TPM_CRB_CTRL_CANCEL_CMD         BIT(0)
					  ^
  sys/dev/tpm/tpm20.h:60:19: note: expanded from macro 'BIT'
  #define BIT(x) (1 << (x))
		    ^

  Such warnings can be useful in C++ contexts, but not so much in kernel
  drivers, where this type of bit twiddling is commonplace.  So disable
  it for this case.

Noticed by:	cem

MFC r357367:

Fix new clang 10.0.0 warnings about converting the result of shift
operations to a boolean in tpm(4):

  sys/dev/tpm/tpm_crb.c:301:32: error: converting the result of '<<' to a boolean; did you mean '(1 << (0)) != 0'? [-Werror,-Wint-in-bool-context]
	  WR4(sc, TPM_CRB_CTRL_CANCEL, !TPM_CRB_CTRL_CANCEL_CMD);
					^
  sys/dev/tpm/tpm_crb.c:73:34: note: expanded from macro 'TPM_CRB_CTRL_CANCEL_CMD'
  #define TPM_CRB_CTRL_CANCEL_CMD         BIT(0)
					  ^
  sys/dev/tpm/tpm20.h:60:19: note: expanded from macro 'BIT'
  #define BIT(x) (1 << (x))
		    ^

In this case, the intent was to clear the zeroth bit, and leave the rest
unaffected.  Therefore, the ~ operator should be used instead.

Noticed by:	cem

MFC r357388:

Amend r357367 by using register values from the TPM datasheet.

As Ian Lepore noted, writing ~1 to a register might have a completely
different effect than doing a regular read-modify-write operation.

Follow the TCG_PC_Client_Platform_TPM_Profile_PTP_2.0_r1.03_v22
datasheet instead, and use the actual values mentioned there:
(uint32_t)1 to cancel the command, (uint32_t)0 to clear the field.

MFC r357391 (by kib):

Fix build.

Obtained from: FreeBSD