From bb29c677b366fdf4f6522cd82228a32567aa98c7 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Tue, 19 Jan 2010 15:20:35 +0900 Subject: sh: Split out MMUCR.URB based entry wiring in to shared helper. Presently this is duplicated between tlb-sh4 and tlb-pteaex. Split the helpers out in to a generic tlb-urb that can be used by any parts equipped with MMUCR.URB. At the same time, move the SH-5 code out-of-line, as we require single global state for DTLB entry wiring. Signed-off-by: Paul Mundt --- arch/sh/mm/tlb-urb.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 arch/sh/mm/tlb-urb.c (limited to 'arch/sh/mm/tlb-urb.c') diff --git a/arch/sh/mm/tlb-urb.c b/arch/sh/mm/tlb-urb.c new file mode 100644 index 000000000000..bb5b9098956d --- /dev/null +++ b/arch/sh/mm/tlb-urb.c @@ -0,0 +1,81 @@ +/* + * arch/sh/mm/tlb-urb.c + * + * TLB entry wiring helpers for URB-equipped parts. + * + * Copyright (C) 2010 Matt Fleming + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include +#include +#include +#include + +/* + * Load the entry for 'addr' into the TLB and wire the entry. + */ +void tlb_wire_entry(struct vm_area_struct *vma, unsigned long addr, pte_t pte) +{ + unsigned long status, flags; + int urb; + + local_irq_save(flags); + + /* Load the entry into the TLB */ + __update_tlb(vma, addr, pte); + + /* ... and wire it up. */ + status = __raw_readl(MMUCR); + urb = (status & MMUCR_URB) >> MMUCR_URB_SHIFT; + status &= ~MMUCR_URB; + + /* + * Make sure we're not trying to wire the last TLB entry slot. + */ + BUG_ON(!--urb); + + urb = urb % MMUCR_URB_NENTRIES; + + status |= (urb << MMUCR_URB_SHIFT); + __raw_writel(status, MMUCR); + ctrl_barrier(); + + local_irq_restore(flags); +} + +/* + * Unwire the last wired TLB entry. + * + * It should also be noted that it is not possible to wire and unwire + * TLB entries in an arbitrary order. If you wire TLB entry N, followed + * by entry N+1, you must unwire entry N+1 first, then entry N. In this + * respect, it works like a stack or LIFO queue. + */ +void tlb_unwire_entry(void) +{ + unsigned long status, flags; + int urb; + + local_irq_save(flags); + + status = __raw_readl(MMUCR); + urb = (status & MMUCR_URB) >> MMUCR_URB_SHIFT; + status &= ~MMUCR_URB; + + /* + * Make sure we're not trying to unwire a TLB entry when none + * have been wired. + */ + BUG_ON(urb++ == MMUCR_URB_NENTRIES); + + urb = urb % MMUCR_URB_NENTRIES; + + status |= (urb << MMUCR_URB_SHIFT); + __raw_writel(status, MMUCR); + ctrl_barrier(); + + local_irq_restore(flags); +} -- cgit v1.2.3