/* Software floating-point emulation. Basic eight-word fraction declaration and manipulation. Copyright (C) 1997,1998,1999 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Richard Henderson (rth@cygnus.com), Jakub Jelinek (jj@ultra.linux.cz) and Peter Maydell (pmaydell@chiark.greenend.org.uk). The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with the GNU C Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #ifndef __MATH_EMU_OP_8_H__ #define __MATH_EMU_OP_8_H__ /* We need just a few things from here for op-4, if we ever need some other macros, they can be added. */ #define _FP_FRAC_DECL_8(X) _FP_W_TYPE X##_f[8] #define _FP_FRAC_HIGH_8(X) (X##_f[7]) #define _FP_FRAC_LOW_8(X) (X##_f[0]) #define _FP_FRAC_WORD_8(X,w) (X##_f[w]) #define _FP_FRAC_SLL_8(X,N) \ do { \ _FP_I_TYPE _up, _down, _skip, _i; \ _skip = (N) / _FP_W_TYPE_SIZE; \ _up = (N) % _FP_W_TYPE_SIZE; \ _down = _FP_W_TYPE_SIZE - _up; \ if (!_up) \ for (_i = 7; _i >= _skip; --_i) \ X##_f[_i] = X##_f[_i-_skip]; \ else \ { \ for (_i = 7; _i > _skip; --_i) \ X##_f[_i] = X##_f[_i-_skip] << _up \ | X##_f[_i-_skip-1] >> _down; \ X##_f[_i--] = X##_f[0] << _up; \ } \ for (; _i >= 0; --_i) \ X##_f[_i] = 0; \ } while (0) #define _FP_FRAC_SRL_8(X,N) \ do { \ _FP_I_TYPE _up, _down, _skip, _i; \ _skip = (N) / _FP_W_TYPE_SIZE; \ _down = (N) % _FP_W_TYPE_SIZE; \ _up = _FP_W_TYPE_SIZE - _down; \ if (!_down) \ for (_i = 0; _i <= 7-_skip; ++_i) \ X##_f[_i] = X##_f[_i+_skip]; \ else \ { \ for (_i = 0; _i < 7-_skip; ++_i) \ X##_f[_i] = X##_f[_i+_skip] >> _down \ | X##_f[_i+_skip+1] << _up; \ X##_f[_i++] = X##_f[7] >> _down; \ } \ for (; _i < 8; ++_i) \ X##_f[_i] = 0; \ } while (0) /* Right shift with sticky-lsb. * What this actually means is that we do a standard right-shift, * but that if any of the bits that fall off the right hand side * were one then we always set the LSbit. */ #define _FP_FRAC_SRS_8(X,N,size) \ do { \ _FP_I_TYPE _up, _down, _skip, _i; \ _FP_W_TYPE _s; \ _skip = (N) / _FP_W_TYPE_SIZE; \ _down = (N) % _FP_W_TYPE_SIZE; \ _up = _FP_W_TYPE_SIZE - _down; \ for (_s = _i = 0; _i < _skip; ++_i) \ _s |= X##_f[_i]; \ _s |= X##_f[_i] << _up; \ /* s is now != 0 if we want to set the LSbit */ \ if (!_down) \ for (_i = 0; _i <= 7-_skip; ++_i) \ X##_f[_i] = X##_f[_i+_skip]; \ else \ { \ for (_i = 0; _i < 7-_skip; ++_i) \ X##_f[_i] = X##_f[_i+_skip] >> _down \ | X##_f[_i+_skip+1] << _up; \ X##_f[_i++] = X##_f[7] >> _down; \ } \ for (; _i < 8; ++_i) \ X##_f[_i] = 0; \ /* don't fix the LSB until the very end when we're sure f[0] is stable */ \ X##_f[0] |= (_s != 0); \ } while (0) #endif orm.submit();'>mode:
authorLv Zheng <lv.zheng@intel.com>2016-06-01 11:03:20 +0800
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2016-06-01 22:44:22 +0200
commit7f9bef9debafcb767d00efb177d0f2edd4940eab (patch)
tree37aa6a6b767b52ab30339404a86b45f57b8cfe0b /Documentation/acpi
parentd1ce3bb95511dacf8b9eea899c421f1b18a3ef6a (diff)
ACPICA / Hardware: Fix old register check in acpi_hw_get_access_bit_width()
The address check in acpi_hw_get_access_bit_width() should be byte width based, not bit width based. This patch fixes this mistake. For those who want to review acpi_hw_access_bit_width(), here is the concerns and the design details of the function: It is supposed that the GAS Address field should be aligned to the byte width indicated by the GAS AccessSize field. Similarly, for the old non GAS register, it is supposed that its Address should be aligned to its Length. For the "AccessSize = 0 (meaning ANY)" case, we try to return the maximum instruction width (64 for MMIO or 32 for PIO) or the user expected access bit width (64 for acpi_read()/acpi_write() or 32 for acpi_hw_read()/ acpi_hw_write()) and it is supposed that the GAS Address field should always be aligned to the maximum expected access bit width (otherwise it can't be accessed using ANY access bit width). The problem is in acpi_tb_init_generic_address(), where the non GAS register's Length is converted into the GAS BitWidth field, its Address is converted into the GAS Address field, and the GAS AccessSize field is left 0 but most of the registers actually cannot be accessed using "ANY" accesses. As a conclusion, when AccessSize = 0 (ANY), the Address should either be aligned to the BitWidth (wrong conversion) or aligned to 32 for PIO or 64 for MMIO (real GAS). Since currently, max_bit_width is 32, then: 1. BitWidth for the wrong conversion is 8,16,32; and 2. The Address of the real GAS should always be aligned to 8,16,32. The address alignment check to exclude false matched real GAS is not necessary. Thus this patch fixes the issue by removing the address alignment check. On the other hand, we in fact could use a simpler check of "reg->bit_width < max_bit_width" to exclude the "BitWidth=64 PIO" case that may be issued from acpi_read()/acpi_write() in the future. Fixes: b314a172ee96 (ACPICA: Hardware: Add optimized access bit width support) Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Acked-by: Mike Marshall <hubcap@omnibond.com> Suggested-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/acpi')