From 0e902f8a24b30344e71b941e8ea802c53c020dfe Mon Sep 17 00:00:00 2001 From: Brooks Davis Date: Wed, 23 Oct 2013 13:32:52 +0000 Subject: Revert r256934, it needs work to build on mips32. --- sys/mips/include/pte.h | 31 +++++++++---------------------- 1 file changed, 9 insertions(+), 22 deletions(-) (limited to 'sys/mips/include') diff --git a/sys/mips/include/pte.h b/sys/mips/include/pte.h index 6a7f0bf8f755..c798eeef5124 100644 --- a/sys/mips/include/pte.h +++ b/sys/mips/include/pte.h @@ -56,26 +56,16 @@ typedef pt_entry_t *pd_entry_t; #define TLBMASK_MASK ((PAGE_MASK >> TLBMASK_SHIFT) << TLBMASK_SHIFT) /* - * FreeBSD/mips page-table entries take a near-identical format to MIPS TLB - * entries, each consisting of two 32-bit or 64-bit values ("EntryHi" and - * "EntryLo"). MIPS4k and MIPS64 both define certain bits in TLB entries as - * reserved, and these must be zero-filled by software. We overload these - * bits in PTE entries to hold PTE_ flags such as RO, W, and MANAGED. - * However, we must mask these out when writing to TLB entries to ensure that - * they do not become visible to hardware -- especially on MIPS64r2 which has - * an extended physical memory space. - * - * When using n64 and n32, shift software-defined bits into the MIPS64r2 - * reserved range, which runs from bit 55 ... 63. In other configurations - * (32-bit MIPS4k and compatible), shift them out to bits 29 ... 31. - * - * NOTE: This means that for 32-bit use of CP0, we aren't able to set the top - * bit of PFN to a non-zero value, as software is using it! This physical - * memory size limit may not be sufficiently enforced elsewhere. + * PFN for EntryLo register. Upper bits are 0, which is to say that + * bit 28 is the last hardware bit; Bits 29 and upwards (EntryLo is + * 64 bit though it can be referred to in 32-bits providing 3 software + * bits safely. We use it as 64 bits to get many software bits, and + * god knows what else.) are unacknowledged by hardware. They may be + * written as anything, but otherwise they have as much meaning as + * other 0 fields. */ #if defined(__mips_n64) || defined(__mips_n32) /* PHYSADDR_64_BIT */ -#define TLBLO_SWBITS_SHIFT (55) -#define TLBLO_SWBITS_CLEAR_SHIFT (9) +#define TLBLO_SWBITS_SHIFT (34) #define TLBLO_PFN_MASK 0x3FFFFFFC0ULL #else #define TLBLO_SWBITS_SHIFT (29) @@ -143,9 +133,6 @@ typedef pt_entry_t *pd_entry_t; * listen to requests to write to it. * W: Wired. ??? * MANAGED:Managed. This PTE maps a managed page. - * - * These bits should not be written into the TLB, so must first be masked out - * explicitly in C, or using CLEAR_PTE_SWBITS() in assembly. */ #define PTE_RO ((pt_entry_t)0x01 << TLBLO_SWBITS_SHIFT) #define PTE_W ((pt_entry_t)0x02 << TLBLO_SWBITS_SHIFT) @@ -175,7 +162,7 @@ typedef pt_entry_t *pd_entry_t; #define PTESIZE 4 #define PTE_L lw #define PTE_MTC0 mtc0 -#define CLEAR_PTE_SWBITS(r) LONG_SLL r, TLBLO_SWBITS_CLEAR_SHIFT; LONG_SRL r, TLBLO_SWBITS_CLEAR_SHIFT /* remove swbits */ +#define CLEAR_PTE_SWBITS(r) sll r, 3; srl r, 3 /* remove 3 high bits */ #endif /* defined(__mips_n64) || defined(__mips_n32) */ #if defined(__mips_n64) -- cgit v1.2.3