mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 03:10:12 +00:00
![Linas Vepstas](/assets/img/avatar_default.png)
The 10Gigabit ethernet device drivers appear to be able to chew up all 256MB of TCE mappings on pSeries systems, as evidenced by numerous error messages: iommu_alloc failed, tbl c0000000010d5c48 vaddr c0000000d875eff0 npages 1 Some experimentation indicates that this is essentially because one 1500 byte ethernet MTU gets mapped as a 64K DMA region when the large 64K pages are enabled. Thus, it doesn't take much to exhaust all of the available DMA mappings for a high-speed card. This patch changes the iommu allocator to work with its own unique, distinct page size. Although the patch is long, its actually quite simple: it just #defines a distinct IOMMU_PAGE_SIZE and then uses this in all the places that matter. As a side effect, it also dramatically improves network performance on platforms with H-calls on iommu translation inserts/removes (since we no longer call it 16 times for a 1500 bytes packet when the iommu HW is still 4k). In the future, we might want to make the IOMMU_PAGE_SIZE a variable in the iommu_table instance, thus allowing support for different HW page sizes in the iommu itself. Signed-off-by: Linas Vepstas <linas@austin.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
77 lines
2.2 KiB
C
77 lines
2.2 KiB
C
/*
|
|
* Copyright (C) 2004 Olof Johansson <olof@lixom.net>, IBM Corporation
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program 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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#ifndef _POWERPC_SYSDEV_DART_H
|
|
#define _POWERPC_SYSDEV_DART_H
|
|
|
|
|
|
/* Offset from base to control register */
|
|
#define DART_CNTL 0
|
|
|
|
/* Offset from base to exception register */
|
|
#define DART_EXCP_U3 0x10
|
|
/* Offset from base to TLB tag registers */
|
|
#define DART_TAGS_U3 0x1000
|
|
|
|
/* U4 registers */
|
|
#define DART_BASE_U4 0x10
|
|
#define DART_SIZE_U4 0x20
|
|
#define DART_EXCP_U4 0x30
|
|
#define DART_TAGS_U4 0x1000
|
|
|
|
/* Control Register fields */
|
|
|
|
/* U3 registers */
|
|
#define DART_CNTL_U3_BASE_MASK 0xfffff
|
|
#define DART_CNTL_U3_BASE_SHIFT 12
|
|
#define DART_CNTL_U3_FLUSHTLB 0x400
|
|
#define DART_CNTL_U3_ENABLE 0x200
|
|
#define DART_CNTL_U3_SIZE_MASK 0x1ff
|
|
#define DART_CNTL_U3_SIZE_SHIFT 0
|
|
|
|
/* U4 registers */
|
|
#define DART_BASE_U4_BASE_MASK 0xffffff
|
|
#define DART_BASE_U4_BASE_SHIFT 0
|
|
#define DART_CNTL_U4_ENABLE 0x80000000
|
|
#define DART_CNTL_U4_IONE 0x40000000
|
|
#define DART_CNTL_U4_FLUSHTLB 0x20000000
|
|
#define DART_CNTL_U4_IDLE 0x10000000
|
|
#define DART_CNTL_U4_PAR_EN 0x08000000
|
|
#define DART_CNTL_U4_IONE_MASK 0x07ffffff
|
|
#define DART_SIZE_U4_SIZE_MASK 0x1fff
|
|
#define DART_SIZE_U4_SIZE_SHIFT 0
|
|
|
|
#define DART_REG(r) (dart + ((r) >> 2))
|
|
#define DART_IN(r) (in_be32(DART_REG(r)))
|
|
#define DART_OUT(r,v) (out_be32(DART_REG(r), (v)))
|
|
|
|
|
|
/* size of table in pages */
|
|
|
|
|
|
/* DART table fields */
|
|
|
|
#define DARTMAP_VALID 0x80000000
|
|
#define DARTMAP_RPNMASK 0x00ffffff
|
|
|
|
|
|
#define DART_PAGE_SHIFT 12
|
|
#define DART_PAGE_SIZE (1 << DART_PAGE_SHIFT)
|
|
|
|
|
|
#endif /* _POWERPC_SYSDEV_DART_H */
|