freebsd-dev/sys/powerpc/pseries/plpar_iommu.c
Nathan Whitehorn c7be335e3e Fix bug in mapppings of multiple pages exposed by updates to the VSCSI
support in QEMU. Each page of a many page mapping was getting mapped to
the same physical address, which is not the desired behavior.

MFC after:	1 week
2015-01-27 07:20:00 +00:00

245 lines
6.9 KiB
C

/*-
* Copyright (c) 2013, Nathan Whitehorn <nwhitehorn@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/libkern.h>
#include <sys/module.h>
#include <sys/vmem.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/openfirm.h>
#include <machine/bus.h>
#include <powerpc/pseries/phyp-hvcall.h>
#include <powerpc/pseries/plpar_iommu.h>
MALLOC_DEFINE(M_PHYPIOMMU, "iommu", "IOMMU data for PAPR LPARs");
struct papr_iommu_map {
uint32_t iobn;
vmem_t *vmem;
struct papr_iommu_map *next;
};
static SLIST_HEAD(iommu_maps, iommu_map) iommu_map_head =
SLIST_HEAD_INITIALIZER(iommu_map_head);
static int papr_supports_stuff_tce = -1;
struct iommu_map {
uint32_t iobn;
vmem_t *vmem;
SLIST_ENTRY(iommu_map) entries;
};
struct dma_window {
struct iommu_map *map;
bus_addr_t start;
bus_addr_t end;
};
int
phyp_iommu_set_dma_tag(device_t bus, device_t dev, bus_dma_tag_t tag)
{
device_t p;
phandle_t node;
cell_t dma_acells, dma_scells, dmawindow[6];
struct iommu_map *i;
int cell;
for (p = dev; device_get_parent(p) != NULL; p = device_get_parent(p)) {
if (ofw_bus_has_prop(p, "ibm,my-dma-window"))
break;
if (ofw_bus_has_prop(p, "ibm,dma-window"))
break;
}
if (p == NULL)
return (ENXIO);
node = ofw_bus_get_node(p);
if (OF_getprop(node, "ibm,#dma-size-cells", &dma_scells,
sizeof(cell_t)) <= 0)
OF_searchprop(node, "#size-cells", &dma_scells, sizeof(cell_t));
if (OF_getprop(node, "ibm,#dma-address-cells", &dma_acells,
sizeof(cell_t)) <= 0)
OF_searchprop(node, "#address-cells", &dma_acells,
sizeof(cell_t));
if (ofw_bus_has_prop(p, "ibm,my-dma-window"))
OF_getprop(node, "ibm,my-dma-window", dmawindow,
sizeof(cell_t)*(dma_scells + dma_acells + 1));
else
OF_getprop(node, "ibm,dma-window", dmawindow,
sizeof(cell_t)*(dma_scells + dma_acells + 1));
struct dma_window *window = malloc(sizeof(struct dma_window),
M_PHYPIOMMU, M_WAITOK);
window->start = 0;
for (cell = 1; cell < 1 + dma_acells; cell++) {
window->start <<= 32;
window->start |= dmawindow[cell];
}
window->end = 0;
for (; cell < 1 + dma_acells + dma_scells; cell++) {
window->end <<= 32;
window->end |= dmawindow[cell];
}
window->end += window->start;
if (bootverbose)
device_printf(dev, "Mapping IOMMU domain %#x\n", dmawindow[0]);
window->map = NULL;
SLIST_FOREACH(i, &iommu_map_head, entries) {
if (i->iobn == dmawindow[0]) {
window->map = i;
break;
}
}
if (window->map == NULL) {
window->map = malloc(sizeof(struct iommu_map), M_PHYPIOMMU,
M_WAITOK);
window->map->iobn = dmawindow[0];
/*
* Allocate IOMMU range beginning at PAGE_SIZE. Some drivers
* (em(4), for example) do not like getting mappings at 0.
*/
window->map->vmem = vmem_create("IOMMU mappings", PAGE_SIZE,
trunc_page(VMEM_ADDR_MAX) - PAGE_SIZE, PAGE_SIZE, 0,
M_BESTFIT | M_NOWAIT);
SLIST_INSERT_HEAD(&iommu_map_head, window->map, entries);
}
/*
* Check experimentally whether we can use H_STUFF_TCE. It is required
* by the spec but some firmware (e.g. QEMU) does not actually support
* it
*/
if (papr_supports_stuff_tce == -1)
papr_supports_stuff_tce = !(phyp_hcall(H_STUFF_TCE,
window->map->iobn, 0, 0, 0) == H_FUNCTION);
bus_dma_tag_set_iommu(tag, bus, window);
return (0);
}
int
phyp_iommu_map(device_t dev, bus_dma_segment_t *segs, int *nsegs,
bus_addr_t min, bus_addr_t max, bus_size_t alignment, bus_addr_t boundary,
void *cookie)
{
struct dma_window *window = cookie;
bus_addr_t minaddr, maxaddr;
bus_addr_t alloced;
bus_size_t allocsize;
int error, i, j;
uint64_t tce;
minaddr = window->start;
maxaddr = window->end;
/* XXX: handle exclusion range in a more useful way */
if (min < maxaddr)
maxaddr = min;
/* XXX: consolidate segs? */
for (i = 0; i < *nsegs; i++) {
allocsize = round_page(segs[i].ds_len +
(segs[i].ds_addr & PAGE_MASK));
error = vmem_xalloc(window->map->vmem, allocsize,
(alignment < PAGE_SIZE) ? PAGE_SIZE : alignment, 0,
boundary, minaddr, maxaddr, M_BESTFIT | M_NOWAIT, &alloced);
if (error != 0) {
panic("VMEM failure: %d\n", error);
return (error);
}
KASSERT(alloced % PAGE_SIZE == 0, ("Alloc not page aligned"));
KASSERT((alloced + (segs[i].ds_addr & PAGE_MASK)) %
alignment == 0,
("Allocated segment does not match alignment constraint"));
tce = trunc_page(segs[i].ds_addr);
tce |= 0x3; /* read/write */
for (j = 0; j < allocsize; j += PAGE_SIZE) {
error = phyp_hcall(H_PUT_TCE, window->map->iobn,
alloced + j, tce + j);
if (error < 0) {
panic("IOMMU mapping error: %d\n", error);
return (ENOMEM);
}
}
segs[i].ds_addr = alloced + (segs[i].ds_addr & PAGE_MASK);
KASSERT(segs[i].ds_addr > 0, ("Address needs to be positive"));
KASSERT(segs[i].ds_addr + segs[i].ds_len < maxaddr,
("Address not in range"));
if (error < 0) {
panic("IOMMU mapping error: %d\n", error);
return (ENOMEM);
}
}
return (0);
}
int
phyp_iommu_unmap(device_t dev, bus_dma_segment_t *segs, int nsegs, void *cookie)
{
struct dma_window *window = cookie;
bus_addr_t pageround;
bus_size_t roundedsize;
int i;
bus_addr_t j;
for (i = 0; i < nsegs; i++) {
pageround = trunc_page(segs[i].ds_addr);
roundedsize = round_page(segs[i].ds_len +
(segs[i].ds_addr & PAGE_MASK));
if (papr_supports_stuff_tce) {
phyp_hcall(H_STUFF_TCE, window->map->iobn, pageround, 0,
roundedsize/PAGE_SIZE);
} else {
for (j = 0; j < roundedsize; j += PAGE_SIZE)
phyp_hcall(H_PUT_TCE, window->map->iobn,
pageround + j, 0);
}
vmem_xfree(window->map->vmem, pageround, roundedsize);
}
return (0);
}