qemu/hw/pci-host/versatile.c
Bernhard Beschow f021f4e9d2 hw/pci/pci: Factor out pci_bus_map_irqs() from pci_bus_irqs()
pci_bus_irqs() coupled together the assignment of pci_set_irq_fn and
pci_map_irq_fn to a PCI bus. This coupling gets in the way when the
pci_map_irq_fn is board-specific while the pci_set_irq_fn is device-
specific.

For example, both of QEMU's PIIX south bridge models have different
pci_map_irq_fn implementations which are board-specific rather than
device-specific. These implementations should therefore reside in board
code. The pci_set_irq_fn's, however, should stay in the device models
because they access memory internal to the model.

Factoring out pci_bus_map_irqs() from pci_bus_irqs() allows the
assignments to be decoupled, resolving the problem described above.

Note also how pci_vpb_realize() which gets touched in this commit
assigns different pci_map_irq_fn's depending on the board.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230109172347.1830-5-shentey@gmail.com>
[PMD: Factor out in vfu_object_set_bus_irq()]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
2023-01-13 16:22:57 +01:00

550 lines
17 KiB
C

/*
* ARM Versatile/PB PCI host controller
*
* Copyright (c) 2006-2009 CodeSourcery.
* Written by Paul Brook
*
* This code is licensed under the LGPL.
*/
#include "qemu/osdep.h"
#include "qemu/units.h"
#include "hw/sysbus.h"
#include "migration/vmstate.h"
#include "hw/irq.h"
#include "hw/pci/pci_device.h"
#include "hw/pci/pci_bus.h"
#include "hw/pci/pci_host.h"
#include "hw/qdev-properties.h"
#include "qemu/log.h"
#include "qemu/module.h"
#include "qom/object.h"
/* Old and buggy versions of QEMU used the wrong mapping from
* PCI IRQs to system interrupt lines. Unfortunately the Linux
* kernel also had the corresponding bug in setting up interrupts
* (so older kernels work on QEMU and not on real hardware).
* We automatically detect these broken kernels and flip back
* to the broken irq mapping by spotting guest writes to the
* PCI_INTERRUPT_LINE register to see where the guest thinks
* interrupts are going to be routed. So we start in state
* ASSUME_OK on reset, and transition to either BROKEN or
* FORCE_OK at the first write to an INTERRUPT_LINE register for
* a slot where broken and correct interrupt mapping would differ.
* Once in either BROKEN or FORCE_OK we never transition again;
* this allows a newer kernel to use the INTERRUPT_LINE
* registers arbitrarily once it has indicated that it isn't
* broken in its init code somewhere.
*
* Unfortunately we have to cope with multiple different
* variants on the broken kernel behaviour:
* phase I (before kernel commit 1bc39ac5d) kernels assume old
* QEMU behaviour, so they use IRQ 27 for all slots
* phase II (1bc39ac5d and later, but before e3e92a7be6) kernels
* swizzle IRQs between slots, but do it wrongly, so they
* work only for every fourth PCI card, and only if (like old
* QEMU) the PCI host device is at slot 0 rather than where
* the h/w actually puts it
* phase III (e3e92a7be6 and later) kernels still swizzle IRQs between
* slots wrongly, but add a fixed offset of 64 to everything
* they write to PCI_INTERRUPT_LINE.
*
* We live in hope of a mythical phase IV kernel which might
* actually behave in ways that work on the hardware. Such a
* kernel should probably start off by writing some value neither
* 27 nor 91 to slot zero's PCI_INTERRUPT_LINE register to
* disable the autodetection. After that it can do what it likes.
*
* Slot % 4 | hw | I | II | III
* -------------------------------
* 0 | 29 | 27 | 27 | 91
* 1 | 30 | 27 | 28 | 92
* 2 | 27 | 27 | 29 | 93
* 3 | 28 | 27 | 30 | 94
*
* Since our autodetection is not perfect we also provide a
* property so the user can make us start in BROKEN or FORCE_OK
* on reset if they know they have a bad or good kernel.
*/
enum {
PCI_VPB_IRQMAP_ASSUME_OK,
PCI_VPB_IRQMAP_BROKEN,
PCI_VPB_IRQMAP_FORCE_OK,
};
struct PCIVPBState {
PCIHostState parent_obj;
qemu_irq irq[4];
MemoryRegion controlregs;
MemoryRegion mem_config;
MemoryRegion mem_config2;
/* Containers representing the PCI address spaces */
MemoryRegion pci_io_space;
MemoryRegion pci_mem_space;
/* Alias regions into PCI address spaces which we expose as sysbus regions.
* The offsets into pci_mem_space are controlled by the imap registers.
*/
MemoryRegion pci_io_window;
MemoryRegion pci_mem_window[3];
PCIBus pci_bus;
PCIDevice pci_dev;
/* Constant for life of device: */
int realview;
uint32_t mem_win_size[3];
uint8_t irq_mapping_prop;
/* Variable state: */
uint32_t imap[3];
uint32_t smap[3];
uint32_t selfid;
uint32_t flags;
uint8_t irq_mapping;
};
typedef struct PCIVPBState PCIVPBState;
static void pci_vpb_update_window(PCIVPBState *s, int i)
{
/* Adjust the offset of the alias region we use for
* the memory window i to account for a change in the
* value of the corresponding IMAP register.
* Note that the semantics of the IMAP register differ
* for realview and versatile variants of the controller.
*/
hwaddr offset;
if (s->realview) {
/* Top bits of register (masked according to window size) provide
* top bits of PCI address.
*/
offset = s->imap[i] & ~(s->mem_win_size[i] - 1);
} else {
/* Bottom 4 bits of register provide top 4 bits of PCI address */
offset = s->imap[i] << 28;
}
memory_region_set_alias_offset(&s->pci_mem_window[i], offset);
}
static void pci_vpb_update_all_windows(PCIVPBState *s)
{
/* Update all alias windows based on the current register state */
int i;
for (i = 0; i < 3; i++) {
pci_vpb_update_window(s, i);
}
}
static int pci_vpb_post_load(void *opaque, int version_id)
{
PCIVPBState *s = opaque;
pci_vpb_update_all_windows(s);
return 0;
}
static const VMStateDescription pci_vpb_vmstate = {
.name = "versatile-pci",
.version_id = 1,
.minimum_version_id = 1,
.post_load = pci_vpb_post_load,
.fields = (VMStateField[]) {
VMSTATE_UINT32_ARRAY(imap, PCIVPBState, 3),
VMSTATE_UINT32_ARRAY(smap, PCIVPBState, 3),
VMSTATE_UINT32(selfid, PCIVPBState),
VMSTATE_UINT32(flags, PCIVPBState),
VMSTATE_UINT8(irq_mapping, PCIVPBState),
VMSTATE_END_OF_LIST()
}
};
#define TYPE_VERSATILE_PCI "versatile_pci"
DECLARE_INSTANCE_CHECKER(PCIVPBState, PCI_VPB,
TYPE_VERSATILE_PCI)
#define TYPE_VERSATILE_PCI_HOST "versatile_pci_host"
DECLARE_INSTANCE_CHECKER(PCIDevice, PCI_VPB_HOST,
TYPE_VERSATILE_PCI_HOST)
typedef enum {
PCI_IMAP0 = 0x0,
PCI_IMAP1 = 0x4,
PCI_IMAP2 = 0x8,
PCI_SELFID = 0xc,
PCI_FLAGS = 0x10,
PCI_SMAP0 = 0x14,
PCI_SMAP1 = 0x18,
PCI_SMAP2 = 0x1c,
} PCIVPBControlRegs;
static void pci_vpb_reg_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
PCIVPBState *s = opaque;
switch (addr) {
case PCI_IMAP0:
case PCI_IMAP1:
case PCI_IMAP2:
{
int win = (addr - PCI_IMAP0) >> 2;
s->imap[win] = val;
pci_vpb_update_window(s, win);
break;
}
case PCI_SELFID:
s->selfid = val;
break;
case PCI_FLAGS:
s->flags = val;
break;
case PCI_SMAP0:
case PCI_SMAP1:
case PCI_SMAP2:
{
int win = (addr - PCI_SMAP0) >> 2;
s->smap[win] = val;
break;
}
default:
qemu_log_mask(LOG_GUEST_ERROR,
"pci_vpb_reg_write: Bad offset %x\n", (int)addr);
break;
}
}
static uint64_t pci_vpb_reg_read(void *opaque, hwaddr addr,
unsigned size)
{
PCIVPBState *s = opaque;
switch (addr) {
case PCI_IMAP0:
case PCI_IMAP1:
case PCI_IMAP2:
{
int win = (addr - PCI_IMAP0) >> 2;
return s->imap[win];
}
case PCI_SELFID:
return s->selfid;
case PCI_FLAGS:
return s->flags;
case PCI_SMAP0:
case PCI_SMAP1:
case PCI_SMAP2:
{
int win = (addr - PCI_SMAP0) >> 2;
return s->smap[win];
}
default:
qemu_log_mask(LOG_GUEST_ERROR,
"pci_vpb_reg_read: Bad offset %x\n", (int)addr);
return 0;
}
}
static const MemoryRegionOps pci_vpb_reg_ops = {
.read = pci_vpb_reg_read,
.write = pci_vpb_reg_write,
.endianness = DEVICE_NATIVE_ENDIAN,
.valid = {
.min_access_size = 4,
.max_access_size = 4,
},
};
static int pci_vpb_broken_irq(int slot, int irq)
{
/* Determine whether this IRQ value for this slot represents a
* known broken Linux kernel behaviour for this slot.
* Return one of the PCI_VPB_IRQMAP_ constants:
* BROKEN : if this definitely looks like a broken kernel
* FORCE_OK : if this definitely looks good
* ASSUME_OK : if we can't tell
*/
slot %= PCI_NUM_PINS;
if (irq == 27) {
if (slot == 2) {
/* Might be a Phase I kernel, or might be a fixed kernel,
* since slot 2 is where we expect this IRQ.
*/
return PCI_VPB_IRQMAP_ASSUME_OK;
}
/* Phase I kernel */
return PCI_VPB_IRQMAP_BROKEN;
}
if (irq == slot + 27) {
/* Phase II kernel */
return PCI_VPB_IRQMAP_BROKEN;
}
if (irq == slot + 27 + 64) {
/* Phase III kernel */
return PCI_VPB_IRQMAP_BROKEN;
}
/* Anything else must be a fixed kernel, possibly using an
* arbitrary irq map.
*/
return PCI_VPB_IRQMAP_FORCE_OK;
}
static void pci_vpb_config_write(void *opaque, hwaddr addr,
uint64_t val, unsigned size)
{
PCIVPBState *s = opaque;
if (!s->realview && (addr & 0xff) == PCI_INTERRUPT_LINE
&& s->irq_mapping == PCI_VPB_IRQMAP_ASSUME_OK) {
uint8_t devfn = addr >> 8;
s->irq_mapping = pci_vpb_broken_irq(PCI_SLOT(devfn), val);
}
pci_data_write(&s->pci_bus, addr, val, size);
}
static uint64_t pci_vpb_config_read(void *opaque, hwaddr addr,
unsigned size)
{
PCIVPBState *s = opaque;
uint32_t val;
val = pci_data_read(&s->pci_bus, addr, size);
return val;
}
static const MemoryRegionOps pci_vpb_config_ops = {
.read = pci_vpb_config_read,
.write = pci_vpb_config_write,
.endianness = DEVICE_NATIVE_ENDIAN,
};
static int pci_vpb_map_irq(PCIDevice *d, int irq_num)
{
PCIVPBState *s = container_of(pci_get_bus(d), PCIVPBState, pci_bus);
if (s->irq_mapping == PCI_VPB_IRQMAP_BROKEN) {
/* Legacy broken IRQ mapping for compatibility with old and
* buggy Linux guests
*/
return irq_num;
}
/* Slot to IRQ mapping for RealView Platform Baseboard 926 backplane
* name slot IntA IntB IntC IntD
* A 31 IRQ28 IRQ29 IRQ30 IRQ27
* B 30 IRQ27 IRQ28 IRQ29 IRQ30
* C 29 IRQ30 IRQ27 IRQ28 IRQ29
* Slot C is for the host bridge; A and B the peripherals.
* Our output irqs 0..3 correspond to the baseboard's 27..30.
*
* This mapping function takes account of an oddity in the PB926
* board wiring, where the FPGA's P_nINTA input is connected to
* the INTB connection on the board PCI edge connector, P_nINTB
* is connected to INTC, and so on, so everything is one number
* further round from where you might expect.
*/
return pci_swizzle_map_irq_fn(d, irq_num + 2);
}
static int pci_vpb_rv_map_irq(PCIDevice *d, int irq_num)
{
/* Slot to IRQ mapping for RealView EB and PB1176 backplane
* name slot IntA IntB IntC IntD
* A 31 IRQ50 IRQ51 IRQ48 IRQ49
* B 30 IRQ49 IRQ50 IRQ51 IRQ48
* C 29 IRQ48 IRQ49 IRQ50 IRQ51
* Slot C is for the host bridge; A and B the peripherals.
* Our output irqs 0..3 correspond to the baseboard's 48..51.
*
* The PB1176 and EB boards don't have the PB926 wiring oddity
* described above; P_nINTA connects to INTA, P_nINTB to INTB
* and so on, which is why this mapping function is different.
*/
return pci_swizzle_map_irq_fn(d, irq_num + 3);
}
static void pci_vpb_set_irq(void *opaque, int irq_num, int level)
{
qemu_irq *pic = opaque;
qemu_set_irq(pic[irq_num], level);
}
static void pci_vpb_reset(DeviceState *d)
{
PCIVPBState *s = PCI_VPB(d);
s->imap[0] = 0;
s->imap[1] = 0;
s->imap[2] = 0;
s->smap[0] = 0;
s->smap[1] = 0;
s->smap[2] = 0;
s->selfid = 0;
s->flags = 0;
s->irq_mapping = s->irq_mapping_prop;
pci_vpb_update_all_windows(s);
}
static void pci_vpb_init(Object *obj)
{
PCIVPBState *s = PCI_VPB(obj);
/* Window sizes for VersatilePB; realview_pci's init will override */
s->mem_win_size[0] = 0x0c000000;
s->mem_win_size[1] = 0x10000000;
s->mem_win_size[2] = 0x10000000;
}
static void pci_vpb_realize(DeviceState *dev, Error **errp)
{
PCIVPBState *s = PCI_VPB(dev);
PCIHostState *h = PCI_HOST_BRIDGE(dev);
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
pci_map_irq_fn mapfn;
int i;
memory_region_init(&s->pci_io_space, OBJECT(s), "pci_io", 4 * GiB);
memory_region_init(&s->pci_mem_space, OBJECT(s), "pci_mem", 4 * GiB);
pci_root_bus_init(&s->pci_bus, sizeof(s->pci_bus), dev, "pci",
&s->pci_mem_space, &s->pci_io_space,
PCI_DEVFN(11, 0), TYPE_PCI_BUS);
h->bus = &s->pci_bus;
object_initialize(&s->pci_dev, sizeof(s->pci_dev), TYPE_VERSATILE_PCI_HOST);
for (i = 0; i < 4; i++) {
sysbus_init_irq(sbd, &s->irq[i]);
}
if (s->realview) {
mapfn = pci_vpb_rv_map_irq;
} else {
mapfn = pci_vpb_map_irq;
}
pci_bus_irqs(&s->pci_bus, pci_vpb_set_irq, s->irq, 4);
pci_bus_map_irqs(&s->pci_bus, mapfn);
/* Our memory regions are:
* 0 : our control registers
* 1 : PCI self config window
* 2 : PCI config window
* 3 : PCI IO window
* 4..6 : PCI memory windows
*/
memory_region_init_io(&s->controlregs, OBJECT(s), &pci_vpb_reg_ops, s,
"pci-vpb-regs", 0x1000);
sysbus_init_mmio(sbd, &s->controlregs);
memory_region_init_io(&s->mem_config, OBJECT(s), &pci_vpb_config_ops, s,
"pci-vpb-selfconfig", 0x1000000);
sysbus_init_mmio(sbd, &s->mem_config);
memory_region_init_io(&s->mem_config2, OBJECT(s), &pci_vpb_config_ops, s,
"pci-vpb-config", 0x1000000);
sysbus_init_mmio(sbd, &s->mem_config2);
/* The window into I/O space is always into a fixed base address;
* its size is the same for both realview and versatile.
*/
memory_region_init_alias(&s->pci_io_window, OBJECT(s), "pci-vbp-io-window",
&s->pci_io_space, 0, 0x100000);
sysbus_init_mmio(sbd, &s->pci_io_space);
/* Create the alias regions corresponding to our three windows onto
* PCI memory space. The sizes vary from board to board; the base
* offsets are guest controllable via the IMAP registers.
*/
for (i = 0; i < 3; i++) {
memory_region_init_alias(&s->pci_mem_window[i], OBJECT(s), "pci-vbp-window",
&s->pci_mem_space, 0, s->mem_win_size[i]);
sysbus_init_mmio(sbd, &s->pci_mem_window[i]);
}
/* TODO Remove once realize propagates to child devices. */
qdev_realize(DEVICE(&s->pci_dev), BUS(&s->pci_bus), errp);
}
static void versatile_pci_host_realize(PCIDevice *d, Error **errp)
{
pci_set_word(d->config + PCI_STATUS,
PCI_STATUS_66MHZ | PCI_STATUS_DEVSEL_MEDIUM);
pci_set_byte(d->config + PCI_LATENCY_TIMER, 0x10);
}
static void versatile_pci_host_class_init(ObjectClass *klass, void *data)
{
PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
DeviceClass *dc = DEVICE_CLASS(klass);
k->realize = versatile_pci_host_realize;
k->vendor_id = PCI_VENDOR_ID_XILINX;
k->device_id = PCI_DEVICE_ID_XILINX_XC2VP30;
k->class_id = PCI_CLASS_PROCESSOR_CO;
/*
* PCI-facing part of the host bridge, not usable without the
* host-facing part, which can't be device_add'ed, yet.
*/
dc->user_creatable = false;
}
static const TypeInfo versatile_pci_host_info = {
.name = TYPE_VERSATILE_PCI_HOST,
.parent = TYPE_PCI_DEVICE,
.instance_size = sizeof(PCIDevice),
.class_init = versatile_pci_host_class_init,
.interfaces = (InterfaceInfo[]) {
{ INTERFACE_CONVENTIONAL_PCI_DEVICE },
{ },
},
};
static Property pci_vpb_properties[] = {
DEFINE_PROP_UINT8("broken-irq-mapping", PCIVPBState, irq_mapping_prop,
PCI_VPB_IRQMAP_ASSUME_OK),
DEFINE_PROP_END_OF_LIST()
};
static void pci_vpb_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
dc->realize = pci_vpb_realize;
dc->reset = pci_vpb_reset;
dc->vmsd = &pci_vpb_vmstate;
device_class_set_props(dc, pci_vpb_properties);
}
static const TypeInfo pci_vpb_info = {
.name = TYPE_VERSATILE_PCI,
.parent = TYPE_PCI_HOST_BRIDGE,
.instance_size = sizeof(PCIVPBState),
.instance_init = pci_vpb_init,
.class_init = pci_vpb_class_init,
};
static void pci_realview_init(Object *obj)
{
PCIVPBState *s = PCI_VPB(obj);
s->realview = 1;
/* The PCI window sizes are different on Realview boards */
s->mem_win_size[0] = 0x01000000;
s->mem_win_size[1] = 0x04000000;
s->mem_win_size[2] = 0x08000000;
}
static const TypeInfo pci_realview_info = {
.name = "realview_pci",
.parent = TYPE_VERSATILE_PCI,
.instance_init = pci_realview_init,
};
static void versatile_pci_register_types(void)
{
type_register_static(&pci_vpb_info);
type_register_static(&pci_realview_info);
type_register_static(&versatile_pci_host_info);
}
type_init(versatile_pci_register_types)