diff options
Diffstat (limited to 'drivers/gpu/pvr/mutils.c')
| -rw-r--r-- | drivers/gpu/pvr/mutils.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/gpu/pvr/mutils.c b/drivers/gpu/pvr/mutils.c new file mode 100644 index 0000000..a012cf5 --- /dev/null +++ b/drivers/gpu/pvr/mutils.c @@ -0,0 +1,136 @@ +/********************************************************************** + * + * Copyright (C) Imagination Technologies Ltd. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful but, except + * as otherwise stated in writing, without any warranty; without even the + * implied warranty of merchantability or fitness for a particular purpose. + * See the GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along with + * this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + * The full GNU General Public License is included in this distribution in + * the file called "COPYING". + * + * Contact Information: + * Imagination Technologies Ltd. <gpl-support@imgtec.com> + * Home Park Estate, Kings Langley, Herts, WD4 8LZ, UK + * + ******************************************************************************/ + +#include <linux/version.h> + +#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,38)) +#ifndef AUTOCONF_INCLUDED +#include <linux/config.h> +#endif +#endif + +#include <linux/spinlock.h> +#include <linux/mm.h> +#include <asm/page.h> +#include <asm/pgtable.h> + +#include "img_defs.h" +#include "pvr_debug.h" +#include "mutils.h" + +#if defined(SUPPORT_LINUX_X86_PAT) +#define PAT_LINUX_X86_WC 1 + +#define PAT_X86_ENTRY_BITS 8 + +#define PAT_X86_BIT_PWT 1U +#define PAT_X86_BIT_PCD 2U +#define PAT_X86_BIT_PAT 4U +#define PAT_X86_BIT_MASK (PAT_X86_BIT_PAT | PAT_X86_BIT_PCD | PAT_X86_BIT_PWT) + +static IMG_BOOL g_write_combining_available = IMG_FALSE; + +#define PROT_TO_PAT_INDEX(v, B) ((v & _PAGE_ ## B) ? PAT_X86_BIT_ ## B : 0) + +static inline IMG_UINT +pvr_pat_index(pgprotval_t prot_val) +{ + IMG_UINT ret = 0; + pgprotval_t val = prot_val & _PAGE_CACHE_MASK; + + ret |= PROT_TO_PAT_INDEX(val, PAT); + ret |= PROT_TO_PAT_INDEX(val, PCD); + ret |= PROT_TO_PAT_INDEX(val, PWT); + + return ret; +} + +static inline IMG_UINT +pvr_pat_entry(u64 pat, IMG_UINT index) +{ + return (IMG_UINT)(pat >> (index * PAT_X86_ENTRY_BITS)) & PAT_X86_BIT_MASK; +} + +static IMG_VOID +PVRLinuxX86PATProbe(IMG_VOID) +{ + + if (cpu_has_pat) + { + u64 pat; + IMG_UINT pat_index; + IMG_UINT pat_entry; + + PVR_TRACE(("%s: PAT available", __FUNCTION__)); + + rdmsrl(MSR_IA32_CR_PAT, pat); + PVR_TRACE(("%s: Top 32 bits of PAT: 0x%.8x", __FUNCTION__, (IMG_UINT)(pat >> 32))); + PVR_TRACE(("%s: Bottom 32 bits of PAT: 0x%.8x", __FUNCTION__, (IMG_UINT)(pat))); + + pat_index = pvr_pat_index(_PAGE_CACHE_WC); + PVR_TRACE(("%s: PAT index for write combining: %u", __FUNCTION__, pat_index)); + + pat_entry = pvr_pat_entry(pat, pat_index); + PVR_TRACE(("%s: PAT entry for write combining: 0x%.2x (should be 0x%.2x)", __FUNCTION__, pat_entry, PAT_LINUX_X86_WC)); + +#if defined(SUPPORT_LINUX_X86_WRITECOMBINE) + g_write_combining_available = (IMG_BOOL)(pat_entry == PAT_LINUX_X86_WC); +#endif + } +#if defined(DEBUG) +#if defined(SUPPORT_LINUX_X86_WRITECOMBINE) + if (g_write_combining_available) + { + PVR_TRACE(("%s: Write combining available via PAT", __FUNCTION__)); + } + else + { + PVR_TRACE(("%s: Write combining not available", __FUNCTION__)); + } +#else + PVR_TRACE(("%s: Write combining disabled in driver build", __FUNCTION__)); +#endif +#endif +} + +pgprot_t +pvr_pgprot_writecombine(pgprot_t prot) +{ + + + return (g_write_combining_available) ? + __pgprot((pgprot_val(prot) & ~_PAGE_CACHE_MASK) | _PAGE_CACHE_WC) : pgprot_noncached(prot); +} +#endif + +IMG_VOID +PVRLinuxMUtilsInit(IMG_VOID) +{ +#if defined(SUPPORT_LINUX_X86_PAT) + PVRLinuxX86PATProbe(); +#endif +} + |