1 files changed, 133 insertions, 0 deletions

diff --git a/drivers/gpu/pvr/mutils.c b/drivers/gpu/pvr/mutils.c
new file mode 100644
index 00000000000..83eab51bb1d
--- /dev/null
+++ b/drivers/gpu/pvr/mutils.c
@@ -0,0 +1,133 @@
+/**********************************************************************
+ *
+ * Copyright(c) 2008 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 
+ *
+ ******************************************************************************/
+
+#ifndef AUTOCONF_INCLUDED
+#include <linux/config.h>
+#endif
+#include <linux/version.h>
+
+#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
+}
+