Files
xen/tools/firmware/hvmloader/pci.c
T
Igor Druzhinin f63b20a213 hvmloader: indicate ACPI tables with "ACPI data" type in e820
Guest kernel does need to know in some cases where the tables are located
to treat these regions properly. One example is kexec process where
the first kernel needs to pass ACPI region locations to the second
kernel which is now a requirement in Linux after 02a3e3cdb7f12 ("x86/boot:
Parse SRAT table and count immovable memory regions") in order for kexec
transition to actually work.

That commit introduced accesses to XSDT and SRAT while the second kernel
is still using kexec transition tables. The transition tables do not have
e820 "reserved" regions mapped where those tables are located currently
in a Xen guest. Instead "ACPI data" regions are mapped with the transition
tables that was introduced by the following commit 6bbeb276b7 ("x86/kexec:
Add the EFI system tables and ACPI tables to the ident map").

Reserve 1MB (out of 16MB currently available) right after ACPI info page for
ACPI tables exclusively but populate this region on demand and only indicate
populated memory as "ACPI data" since according to ACPI spec that memory is
reclaimable by the guest if necessary. That is close to how we treat
the same ACPI data in PVH guests. 1MB should be enough for now but could be
later extended if required.

Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 8efa46516c
master date: 2020-09-09 17:56:13 +0200
2020-09-22 17:40:36 +02:00

566 lines
21 KiB
C

/*
* pci.c: HVM PCI setup.
*
* Leendert van Doorn, leendert@watson.ibm.com
* Copyright (c) 2005, International Business Machines Corporation.
*
* Copyright (c) 2006, Keir Fraser, XenSource Inc.
*
* 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 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, see <http://www.gnu.org/licenses/>.
*/
#include "util.h"
#include "hypercall.h"
#include "config.h"
#include "pci_regs.h"
#include <xen/memory.h>
#include <xen/hvm/ioreq.h>
#include <xen/hvm/hvm_xs_strings.h>
#include <xen/hvm/e820.h>
unsigned long pci_mem_start = HVM_BELOW_4G_MMIO_START;
unsigned long pci_mem_end = PCI_MEM_END;
uint64_t pci_hi_mem_start = 0, pci_hi_mem_end = 0;
enum virtual_vga virtual_vga = VGA_none;
unsigned long igd_opregion_pgbase = 0;
/* Check if the specified range conflicts with any reserved device memory. */
static bool check_overlap_all(uint64_t start, uint64_t size)
{
unsigned int i;
for ( i = 0; i < memory_map.nr_map; i++ )
{
if ( memory_map.map[i].type == E820_RESERVED &&
check_overlap(start, size,
memory_map.map[i].addr,
memory_map.map[i].size) )
return true;
}
return false;
}
/* Find the lowest RMRR ending above base but below 4G. */
static int find_next_rmrr(uint32_t base)
{
unsigned int i;
int next_rmrr = -1;
uint64_t end, min_end = GB(4);
for ( i = 0; i < memory_map.nr_map ; i++ )
{
end = memory_map.map[i].addr + memory_map.map[i].size;
if ( memory_map.map[i].type == E820_RESERVED &&
end > base && end <= min_end )
{
next_rmrr = i;
min_end = end;
}
}
return next_rmrr;
}
void pci_setup(void)
{
uint8_t is_64bar, using_64bar, bar64_relocate = 0;
uint32_t devfn, bar_reg, cmd, bar_data, bar_data_upper;
uint64_t base, bar_sz, bar_sz_upper, mmio_total = 0;
uint32_t vga_devfn = 256;
uint16_t class, vendor_id, device_id;
unsigned int bar, pin, link, isa_irq;
uint8_t pci_devfn_decode_type[256] = {};
/* Resources assignable to PCI devices via BARs. */
struct resource {
uint64_t base, max;
} *resource, mem_resource, high_mem_resource, io_resource;
/* Create a list of device BARs in descending order of size. */
struct bars {
uint32_t is_64bar;
uint32_t devfn;
uint32_t bar_reg;
uint64_t bar_sz;
} *bars = (struct bars *)scratch_start;
unsigned int i, nr_bars = 0;
uint64_t mmio_hole_size = 0;
const char *s;
/*
* Do we allow hvmloader to relocate guest memory in order to
* increase the size of the lowmem MMIO hole? Defaulting to 1
* here will mean that non-libxl toolstacks (including xend and
* home-grown ones) means that those using qemu-xen will still
* experience the memory relocation bug described below; but it
* also means that those using qemu-traditional will *not*
* experience any change; and it also means that there is a
* work-around for those using qemu-xen, namely switching to
* qemu-traditional.
*
* If we defaulted to 0, and failing to resize the hole caused any
* problems with qemu-traditional, then there is no work-around.
*
* Since xend can only use qemu-traditional, I think this is the
* option that will have the least impact.
*/
bool allow_memory_relocate = 1;
BUILD_BUG_ON((typeof(*pci_devfn_decode_type))PCI_COMMAND_IO !=
PCI_COMMAND_IO);
BUILD_BUG_ON((typeof(*pci_devfn_decode_type))PCI_COMMAND_MEMORY !=
PCI_COMMAND_MEMORY);
BUILD_BUG_ON((typeof(*pci_devfn_decode_type))PCI_COMMAND_MASTER !=
PCI_COMMAND_MASTER);
s = xenstore_read(HVM_XS_ALLOW_MEMORY_RELOCATE, NULL);
if ( s )
allow_memory_relocate = strtoll(s, NULL, 0);
printf("Relocating guest memory for lowmem MMIO space %s\n",
allow_memory_relocate?"enabled":"disabled");
s = xenstore_read("platform/mmio_hole_size", NULL);
if ( s )
mmio_hole_size = strtoll(s, NULL, 0);
/* Program PCI-ISA bridge with appropriate link routes. */
isa_irq = 0;
for ( link = 0; link < 4; link++ )
{
do { isa_irq = (isa_irq + 1) & 15;
} while ( !(PCI_ISA_IRQ_MASK & (1U << isa_irq)) );
pci_writeb(PCI_ISA_DEVFN, 0x60 + link, isa_irq);
printf("PCI-ISA link %u routed to IRQ%u\n", link, isa_irq);
}
/* Program ELCR to match PCI-wired IRQs. */
outb(0x4d0, (uint8_t)(PCI_ISA_IRQ_MASK >> 0));
outb(0x4d1, (uint8_t)(PCI_ISA_IRQ_MASK >> 8));
/* Scan the PCI bus and map resources. */
for ( devfn = 0; devfn < 256; devfn++ )
{
class = pci_readw(devfn, PCI_CLASS_DEVICE);
vendor_id = pci_readw(devfn, PCI_VENDOR_ID);
device_id = pci_readw(devfn, PCI_DEVICE_ID);
if ( (vendor_id == 0xffff) && (device_id == 0xffff) )
continue;
ASSERT((devfn != PCI_ISA_DEVFN) ||
((vendor_id == 0x8086) && (device_id == 0x7000)));
switch ( class )
{
case 0x0300:
/* If emulated VGA is found, preserve it as primary VGA. */
if ( (vendor_id == 0x1234) && (device_id == 0x1111) )
{
vga_devfn = devfn;
virtual_vga = VGA_std;
}
else if ( (vendor_id == 0x1013) && (device_id == 0xb8) )
{
vga_devfn = devfn;
virtual_vga = VGA_cirrus;
}
else if ( virtual_vga == VGA_none )
{
vga_devfn = devfn;
virtual_vga = VGA_pt;
if ( vendor_id == 0x8086 )
{
igd_opregion_pgbase = mem_hole_alloc(IGD_OPREGION_PAGES);
/*
* Write the the OpRegion offset to give the opregion
* address to the device model. The device model will trap
* and map the OpRegion at the give address.
*/
pci_writel(vga_devfn, PCI_INTEL_OPREGION,
igd_opregion_pgbase << PAGE_SHIFT);
}
}
break;
case 0x0680:
/* PIIX4 ACPI PM. Special device with special PCI config space. */
ASSERT((vendor_id == 0x8086) && (device_id == 0x7113));
pci_writew(devfn, 0x20, 0x0000); /* No smb bus IO enable */
pci_writew(devfn, 0xd2, 0x0000); /* No smb bus IO enable */
pci_writew(devfn, 0x22, 0x0000);
pci_writew(devfn, 0x3c, 0x0009); /* Hardcoded IRQ9 */
pci_writew(devfn, 0x3d, 0x0001);
pci_writel(devfn, 0x40, ACPI_PM1A_EVT_BLK_ADDRESS_V1 | 1);
pci_writeb(devfn, 0x80, 0x01); /* enable PM io space */
break;
case 0x0101:
if ( vendor_id == 0x8086 )
{
/* Intel ICHs since PIIX3: enable IDE legacy mode. */
pci_writew(devfn, 0x40, 0x8000); /* enable IDE0 */
pci_writew(devfn, 0x42, 0x8000); /* enable IDE1 */
}
break;
}
/*
* It is recommended that BAR programming be done whilst decode
* bits are cleared to avoid incorrect mappings being created.
* When 64-bit memory BAR is programmed, first by writing the
* lower half and then the upper half, which maps to an address
* under 4G, as soon as lower half is wriiten, replacing any RAM
* mapped in that address, which is not restored back after the
* upper half is written and PCI memory is correctly mapped to
* its intended high mem address.
*/
cmd = pci_readw(devfn, PCI_COMMAND);
cmd &= ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO);
pci_writew(devfn, PCI_COMMAND, cmd);
/* Map the I/O memory and port resources. */
for ( bar = 0; bar < 7; bar++ )
{
bar_sz_upper = 0;
bar_reg = PCI_BASE_ADDRESS_0 + 4*bar;
if ( bar == 6 )
bar_reg = PCI_ROM_ADDRESS;
bar_data = pci_readl(devfn, bar_reg);
if ( bar_reg != PCI_ROM_ADDRESS )
{
is_64bar = !!((bar_data & (PCI_BASE_ADDRESS_SPACE |
PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
(PCI_BASE_ADDRESS_SPACE_MEMORY |
PCI_BASE_ADDRESS_MEM_TYPE_64));
pci_writel(devfn, bar_reg, ~0);
}
else
{
is_64bar = 0;
pci_writel(devfn, bar_reg,
(bar_data | PCI_ROM_ADDRESS_MASK) &
~PCI_ROM_ADDRESS_ENABLE);
}
bar_sz = pci_readl(devfn, bar_reg);
pci_writel(devfn, bar_reg, bar_data);
if ( bar_reg != PCI_ROM_ADDRESS )
bar_sz &= (((bar_data & PCI_BASE_ADDRESS_SPACE) ==
PCI_BASE_ADDRESS_SPACE_MEMORY) ?
PCI_BASE_ADDRESS_MEM_MASK :
(PCI_BASE_ADDRESS_IO_MASK & 0xffff));
else
bar_sz &= PCI_ROM_ADDRESS_MASK;
if (is_64bar) {
bar_data_upper = pci_readl(devfn, bar_reg + 4);
pci_writel(devfn, bar_reg + 4, ~0);
bar_sz_upper = pci_readl(devfn, bar_reg + 4);
pci_writel(devfn, bar_reg + 4, bar_data_upper);
bar_sz = (bar_sz_upper << 32) | bar_sz;
}
bar_sz &= ~(bar_sz - 1);
if ( bar_sz == 0 )
continue;
for ( i = 0; i < nr_bars; i++ )
if ( bars[i].bar_sz < bar_sz )
break;
if ( i != nr_bars )
memmove(&bars[i+1], &bars[i], (nr_bars-i) * sizeof(*bars));
bars[i].is_64bar = is_64bar;
bars[i].devfn = devfn;
bars[i].bar_reg = bar_reg;
bars[i].bar_sz = bar_sz;
if ( ((bar_data & PCI_BASE_ADDRESS_SPACE) ==
PCI_BASE_ADDRESS_SPACE_MEMORY) ||
(bar_reg == PCI_ROM_ADDRESS) )
mmio_total += bar_sz;
nr_bars++;
/*The upper half is already calculated, skip it! */
if (is_64bar)
bar++;
}
/* Map the interrupt. */
pin = pci_readb(devfn, PCI_INTERRUPT_PIN);
if ( pin != 0 )
{
/* This is the barber's pole mapping used by Xen. */
link = ((pin - 1) + (devfn >> 3)) & 3;
isa_irq = pci_readb(PCI_ISA_DEVFN, 0x60 + link);
pci_writeb(devfn, PCI_INTERRUPT_LINE, isa_irq);
printf("pci dev %02x:%x INT%c->IRQ%u\n",
devfn>>3, devfn&7, 'A'+pin-1, isa_irq);
}
/* Enable bus master for this function later */
pci_devfn_decode_type[devfn] = PCI_COMMAND_MASTER;
}
if ( mmio_hole_size )
{
uint64_t max_ram_below_4g = GB(4) - mmio_hole_size;
if ( max_ram_below_4g > HVM_BELOW_4G_MMIO_START )
{
printf("max_ram_below_4g=0x"PRIllx
" too big for mmio_hole_size=0x"PRIllx
" has been ignored.\n",
PRIllx_arg(max_ram_below_4g),
PRIllx_arg(mmio_hole_size));
}
else
{
pci_mem_start = max_ram_below_4g;
printf("pci_mem_start=0x%lx (was 0x%x) for mmio_hole_size=%lu\n",
pci_mem_start, HVM_BELOW_4G_MMIO_START,
(long)mmio_hole_size);
}
}
else
{
/*
* At the moment qemu-xen can't deal with relocated memory regions.
* It's too close to the release to make a proper fix; for now,
* only allow the MMIO hole to grow large enough to move guest memory
* if we're running qemu-traditional. Items that don't fit will be
* relocated into the 64-bit address space.
*
* This loop now does the following:
* - If allow_memory_relocate, increase the MMIO hole until it's
* big enough, or until it's 2GiB
* - If !allow_memory_relocate, increase the MMIO hole until it's
* big enough, or until it's 2GiB, or until it overlaps guest
* memory
*/
while ( (mmio_total > (pci_mem_end - pci_mem_start))
&& ((pci_mem_start << 1) != 0)
&& (allow_memory_relocate
|| (((pci_mem_start << 1) >> PAGE_SHIFT)
>= hvm_info->low_mem_pgend)) )
pci_mem_start <<= 1;
/*
* Try to accommodate RMRRs in our MMIO region on a best-effort basis.
* If we have RMRRs in the range, then make pci_mem_start just after
* hvm_info->low_mem_pgend.
*/
if ( pci_mem_start > (hvm_info->low_mem_pgend << PAGE_SHIFT) &&
check_overlap_all(pci_mem_start, pci_mem_end-pci_mem_start) )
pci_mem_start = hvm_info->low_mem_pgend << PAGE_SHIFT;
}
if ( mmio_total > (pci_mem_end - pci_mem_start) )
{
printf("Low MMIO hole not large enough for all devices,"
" relocating some BARs to 64-bit\n");
bar64_relocate = 1;
}
/* Relocate RAM that overlaps PCI space (in 64k-page chunks). */
while ( (pci_mem_start >> PAGE_SHIFT) < hvm_info->low_mem_pgend )
{
struct xen_add_to_physmap xatp;
unsigned int nr_pages = min_t(
unsigned int,
hvm_info->low_mem_pgend - (pci_mem_start >> PAGE_SHIFT),
(1u << 16) - 1);
if ( hvm_info->high_mem_pgend == 0 )
hvm_info->high_mem_pgend = 1ull << (32 - PAGE_SHIFT);
hvm_info->low_mem_pgend -= nr_pages;
printf("Relocating 0x%x pages from "PRIllx" to "PRIllx\
" for lowmem MMIO hole\n",
nr_pages,
PRIllx_arg(((uint64_t)hvm_info->low_mem_pgend)<<PAGE_SHIFT),
PRIllx_arg(((uint64_t)hvm_info->high_mem_pgend)<<PAGE_SHIFT));
xatp.domid = DOMID_SELF;
xatp.space = XENMAPSPACE_gmfn_range;
xatp.idx = hvm_info->low_mem_pgend;
xatp.gpfn = hvm_info->high_mem_pgend;
xatp.size = nr_pages;
if ( hypercall_memory_op(XENMEM_add_to_physmap, &xatp) != 0 )
BUG();
hvm_info->high_mem_pgend += nr_pages;
}
/* Sync memory map[] if necessary. */
adjust_memory_map();
high_mem_resource.base = ((uint64_t)hvm_info->high_mem_pgend) << PAGE_SHIFT;
if ( high_mem_resource.base < GB(4) )
{
if ( hvm_info->high_mem_pgend != 0 )
printf("WARNING: hvm_info->high_mem_pgend %x"
" does not point into high memory!",
hvm_info->high_mem_pgend);
high_mem_resource.base = GB(4);
}
printf("%sRAM in high memory; setting high_mem resource base to "PRIllx"\n",
hvm_info->high_mem_pgend?"":"No ",
PRIllx_arg(high_mem_resource.base));
high_mem_resource.max = 1ull << cpu_phys_addr();
mem_resource.base = pci_mem_start;
mem_resource.max = pci_mem_end;
io_resource.base = 0xc000;
io_resource.max = 0x10000;
/* Assign iomem and ioport resources in descending order of size. */
for ( i = 0; i < nr_bars; i++ )
{
devfn = bars[i].devfn;
bar_reg = bars[i].bar_reg;
bar_sz = bars[i].bar_sz;
/*
* Relocate to high memory if the total amount of MMIO needed
* is more than the low MMIO available. Because devices are
* processed in order of bar_sz, this will preferentially
* relocate larger devices to high memory first.
*
* NB: The code here is rather fragile, as the check here to see
* whether bar_sz will fit in the low MMIO region doesn't match the
* real check made below, which involves aligning the base offset of the
* bar with the size of the bar itself. As it happens, this will always
* be satisfied because:
* - The first one will succeed because the MMIO hole can only start at
* 0x{f,e,c,8}00000000. If it fits, it will be aligned properly.
* - All subsequent ones will be aligned because the list is ordered
* large to small, and bar_sz is always a power of 2. (At least
* the code here assumes it to be.)
* Should either of those two conditions change, this code will break.
*/
using_64bar = bars[i].is_64bar && bar64_relocate
&& (mmio_total > (mem_resource.max - mem_resource.base));
bar_data = pci_readl(devfn, bar_reg);
if ( (bar_data & PCI_BASE_ADDRESS_SPACE) ==
PCI_BASE_ADDRESS_SPACE_MEMORY )
{
/* Mapping high memory if PCI device is 64 bits bar */
if ( using_64bar ) {
if ( high_mem_resource.base & (bar_sz - 1) )
high_mem_resource.base = high_mem_resource.base -
(high_mem_resource.base & (bar_sz - 1)) + bar_sz;
if ( !pci_hi_mem_start )
pci_hi_mem_start = high_mem_resource.base;
resource = &high_mem_resource;
bar_data &= ~PCI_BASE_ADDRESS_MEM_MASK;
}
else {
resource = &mem_resource;
bar_data &= ~PCI_BASE_ADDRESS_MEM_MASK;
}
mmio_total -= bar_sz;
}
else
{
resource = &io_resource;
bar_data &= ~PCI_BASE_ADDRESS_IO_MASK;
}
base = (resource->base + bar_sz - 1) & ~(uint64_t)(bar_sz - 1);
/* If we're using mem_resource, check for RMRR conflicts. */
if ( resource == &mem_resource)
{
int next_rmrr = find_next_rmrr(base);
while ( next_rmrr >= 0 &&
check_overlap(base, bar_sz,
memory_map.map[next_rmrr].addr,
memory_map.map[next_rmrr].size) )
{
base = memory_map.map[next_rmrr].addr +
memory_map.map[next_rmrr].size;
base = (base + bar_sz - 1) & ~(bar_sz - 1);
next_rmrr = find_next_rmrr(base);
}
}
bar_data |= (uint32_t)base;
bar_data_upper = (uint32_t)(base >> 32);
base += bar_sz;
if ( (base < resource->base) || (base > resource->max) )
{
printf("pci dev %02x:%x bar %02x size "PRIllx": no space for "
"resource!\n", devfn>>3, devfn&7, bar_reg,
PRIllx_arg(bar_sz));
continue;
}
resource->base = base;
pci_writel(devfn, bar_reg, bar_data);
if (using_64bar)
pci_writel(devfn, bar_reg + 4, bar_data_upper);
printf("pci dev %02x:%x bar %02x size "PRIllx": %x%08x\n",
devfn>>3, devfn&7, bar_reg,
PRIllx_arg(bar_sz),
bar_data_upper, bar_data);
if ( (bar_reg == PCI_ROM_ADDRESS) ||
((bar_data & PCI_BASE_ADDRESS_SPACE) ==
PCI_BASE_ADDRESS_SPACE_MEMORY) )
pci_devfn_decode_type[devfn] |= PCI_COMMAND_MEMORY;
else
pci_devfn_decode_type[devfn] |= PCI_COMMAND_IO;
}
if ( pci_hi_mem_start )
{
/*
* Make end address alignment match the start address one's so that
* fewer variable range MTRRs are needed to cover the range.
*/
pci_hi_mem_end = ((high_mem_resource.base - 1) |
((pci_hi_mem_start & -pci_hi_mem_start) - 1)) + 1;
}
if ( vga_devfn != 256 )
{
/*
* VGA registers live in I/O space so ensure that primary VGA
* has IO enabled, even if there is no I/O BAR on that
* particular device.
*/
pci_devfn_decode_type[vga_devfn] |= PCI_COMMAND_IO;
}
/* Enable bus master, memory and I/O decode for all valid functions. */
for ( devfn = 0; devfn < 256; devfn++ )
if ( pci_devfn_decode_type[devfn] )
{
cmd = pci_readw(devfn, PCI_COMMAND);
cmd |= pci_devfn_decode_type[devfn];
pci_writew(devfn, PCI_COMMAND, cmd);
}
}
/*
* Local variables:
* mode: C
* c-file-style: "BSD"
* c-basic-offset: 4
* tab-width: 4
* indent-tabs-mode: nil
* End:
*/