xemu/hw/hppa/machine.c
Helge Deller 4a4554c6c5 hppa: Add support for an emulated TOC/NMI button.
Almost all PA-RISC machines have either a button that is labeled with 'TOC' or
a BMC/GSP function to trigger a TOC.  TOC is a non-maskable interrupt that is
sent to the processor.  This can be used for diagnostic purposes like obtaining
a stack trace/register dump or to enter KDB/KGDB in Linux.

This patch adds support for such an emulated TOC button.

It wires up the qemu monitor "nmi" command to trigger a TOC.  For that it
provides the hppa_nmi function which is assigned to the nmi_monitor_handler
function pointer.  When called it raises the EXCP_TOC hardware interrupt in the
hppa_cpu_do_interrupt() function.  The interrupt function then calls the
architecturally defined TOC function in SeaBIOS-hppa firmware (at fixed address
0xf0000000).

According to the PA-RISC PDC specification, the SeaBIOS firmware then writes
the CPU registers into PIM (processor internal memmory) for later analysis.  In
order to write all registers it needs to know the contents of the CPU "shadow
registers" and the IASQ- and IAOQ-back values. The IAOQ/IASQ values are
provided by qemu in shadow registers when entering the SeaBIOS TOC function.
This patch adds a new aritificial opcode "getshadowregs" (0xfffdead2) which
restores the original values of the shadow registers. With this opcode SeaBIOS
can store those registers as well into PIM before calling an OS-provided TOC
handler.

To trigger a TOC, switch to the qemu monitor with Ctrl-A C, and type in the
command "nmi".  After the TOC started the OS-debugger, exit the qemu monitor
with Ctrl-A C.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2022-02-02 18:46:42 +01:00

408 lines
13 KiB
C

/*
* QEMU HPPA hardware system emulator.
* Copyright 2018 Helge Deller <deller@gmx.de>
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/datadir.h"
#include "cpu.h"
#include "elf.h"
#include "hw/loader.h"
#include "qemu/error-report.h"
#include "sysemu/reset.h"
#include "sysemu/sysemu.h"
#include "sysemu/runstate.h"
#include "hw/rtc/mc146818rtc.h"
#include "hw/timer/i8254.h"
#include "hw/char/serial.h"
#include "hw/net/lasi_82596.h"
#include "hw/nmi.h"
#include "hppa_sys.h"
#include "qemu/units.h"
#include "qapi/error.h"
#include "net/net.h"
#include "qemu/log.h"
#include "net/net.h"
#define MAX_IDE_BUS 2
#define MIN_SEABIOS_HPPA_VERSION 1 /* require at least this fw version */
#define HPA_POWER_BUTTON (FIRMWARE_END - 0x10)
static void hppa_powerdown_req(Notifier *n, void *opaque)
{
hwaddr soft_power_reg = HPA_POWER_BUTTON;
uint32_t val;
val = ldl_be_phys(&address_space_memory, soft_power_reg);
if ((val >> 8) == 0) {
/* immediately shut down when under hardware control */
qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
return;
}
/* clear bit 31 to indicate that the power switch was pressed. */
val &= ~1;
stl_be_phys(&address_space_memory, soft_power_reg, val);
}
static Notifier hppa_system_powerdown_notifier = {
.notify = hppa_powerdown_req
};
static ISABus *hppa_isa_bus(void)
{
ISABus *isa_bus;
qemu_irq *isa_irqs;
MemoryRegion *isa_region;
isa_region = g_new(MemoryRegion, 1);
memory_region_init_io(isa_region, NULL, &hppa_pci_ignore_ops,
NULL, "isa-io", 0x800);
memory_region_add_subregion(get_system_memory(), IDE_HPA,
isa_region);
isa_bus = isa_bus_new(NULL, get_system_memory(), isa_region,
&error_abort);
isa_irqs = i8259_init(isa_bus,
/* qemu_allocate_irq(dino_set_isa_irq, s, 0)); */
NULL);
isa_bus_irqs(isa_bus, isa_irqs);
return isa_bus;
}
static uint64_t cpu_hppa_to_phys(void *opaque, uint64_t addr)
{
addr &= (0x10000000 - 1);
return addr;
}
static HPPACPU *cpu[HPPA_MAX_CPUS];
static uint64_t firmware_entry;
static void fw_cfg_boot_set(void *opaque, const char *boot_device,
Error **errp)
{
fw_cfg_modify_i16(opaque, FW_CFG_BOOT_DEVICE, boot_device[0]);
}
static FWCfgState *create_fw_cfg(MachineState *ms)
{
FWCfgState *fw_cfg;
uint64_t val;
fw_cfg = fw_cfg_init_mem(FW_CFG_IO_BASE, FW_CFG_IO_BASE + 4);
fw_cfg_add_i16(fw_cfg, FW_CFG_NB_CPUS, ms->smp.cpus);
fw_cfg_add_i16(fw_cfg, FW_CFG_MAX_CPUS, HPPA_MAX_CPUS);
fw_cfg_add_i64(fw_cfg, FW_CFG_RAM_SIZE, ms->ram_size);
val = cpu_to_le64(MIN_SEABIOS_HPPA_VERSION);
fw_cfg_add_file(fw_cfg, "/etc/firmware-min-version",
g_memdup(&val, sizeof(val)), sizeof(val));
val = cpu_to_le64(HPPA_TLB_ENTRIES);
fw_cfg_add_file(fw_cfg, "/etc/cpu/tlb_entries",
g_memdup(&val, sizeof(val)), sizeof(val));
val = cpu_to_le64(HPPA_BTLB_ENTRIES);
fw_cfg_add_file(fw_cfg, "/etc/cpu/btlb_entries",
g_memdup(&val, sizeof(val)), sizeof(val));
val = cpu_to_le64(HPA_POWER_BUTTON);
fw_cfg_add_file(fw_cfg, "/etc/power-button-addr",
g_memdup(&val, sizeof(val)), sizeof(val));
fw_cfg_add_i16(fw_cfg, FW_CFG_BOOT_DEVICE, ms->boot_order[0]);
qemu_register_boot_set(fw_cfg_boot_set, fw_cfg);
return fw_cfg;
}
static void machine_hppa_init(MachineState *machine)
{
const char *kernel_filename = machine->kernel_filename;
const char *kernel_cmdline = machine->kernel_cmdline;
const char *initrd_filename = machine->initrd_filename;
DeviceState *dev;
PCIBus *pci_bus;
ISABus *isa_bus;
qemu_irq rtc_irq, serial_irq;
char *firmware_filename;
uint64_t firmware_low, firmware_high;
long size;
uint64_t kernel_entry = 0, kernel_low, kernel_high;
MemoryRegion *addr_space = get_system_memory();
MemoryRegion *rom_region;
MemoryRegion *cpu_region;
long i;
unsigned int smp_cpus = machine->smp.cpus;
SysBusDevice *s;
/* Create CPUs. */
for (i = 0; i < smp_cpus; i++) {
char *name = g_strdup_printf("cpu%ld-io-eir", i);
cpu[i] = HPPA_CPU(cpu_create(machine->cpu_type));
cpu_region = g_new(MemoryRegion, 1);
memory_region_init_io(cpu_region, OBJECT(cpu[i]), &hppa_io_eir_ops,
cpu[i], name, 4);
memory_region_add_subregion(addr_space, CPU_HPA + i * 0x1000,
cpu_region);
g_free(name);
}
/* Main memory region. */
if (machine->ram_size > 3 * GiB) {
error_report("RAM size is currently restricted to 3GB");
exit(EXIT_FAILURE);
}
memory_region_add_subregion_overlap(addr_space, 0, machine->ram, -1);
/* Init Lasi chip */
lasi_init(addr_space);
/* Init Dino (PCI host bus chip). */
pci_bus = dino_init(addr_space, &rtc_irq, &serial_irq);
assert(pci_bus);
/* Create ISA bus. */
isa_bus = hppa_isa_bus();
assert(isa_bus);
/* Realtime clock, used by firmware for PDC_TOD call. */
mc146818_rtc_init(isa_bus, 2000, rtc_irq);
/* Serial code setup. */
if (serial_hd(0)) {
uint32_t addr = DINO_UART_HPA + 0x800;
serial_mm_init(addr_space, addr, 0, serial_irq,
115200, serial_hd(0), DEVICE_BIG_ENDIAN);
}
/* fw_cfg configuration interface */
create_fw_cfg(machine);
/* SCSI disk setup. */
dev = DEVICE(pci_create_simple(pci_bus, -1, "lsi53c895a"));
lsi53c8xx_handle_legacy_cmdline(dev);
/* Graphics setup. */
if (machine->enable_graphics && vga_interface_type != VGA_NONE) {
dev = qdev_new("artist");
s = SYS_BUS_DEVICE(dev);
sysbus_realize_and_unref(s, &error_fatal);
sysbus_mmio_map(s, 0, LASI_GFX_HPA);
sysbus_mmio_map(s, 1, ARTIST_FB_ADDR);
}
/* Network setup. */
for (i = 0; i < nb_nics; i++) {
if (!enable_lasi_lan()) {
pci_nic_init_nofail(&nd_table[i], pci_bus, "tulip", NULL);
}
}
/* register power switch emulation */
qemu_register_powerdown_notifier(&hppa_system_powerdown_notifier);
/* Load firmware. Given that this is not "real" firmware,
but one explicitly written for the emulation, we might as
well load it directly from an ELF image. */
firmware_filename = qemu_find_file(QEMU_FILE_TYPE_BIOS,
machine->firmware ?: "hppa-firmware.img");
if (firmware_filename == NULL) {
error_report("no firmware provided");
exit(1);
}
size = load_elf(firmware_filename, NULL, NULL, NULL,
&firmware_entry, &firmware_low, &firmware_high, NULL,
true, EM_PARISC, 0, 0);
/* Unfortunately, load_elf sign-extends reading elf32. */
firmware_entry = (target_ureg)firmware_entry;
firmware_low = (target_ureg)firmware_low;
firmware_high = (target_ureg)firmware_high;
if (size < 0) {
error_report("could not load firmware '%s'", firmware_filename);
exit(1);
}
qemu_log_mask(CPU_LOG_PAGE, "Firmware loaded at 0x%08" PRIx64
"-0x%08" PRIx64 ", entry at 0x%08" PRIx64 ".\n",
firmware_low, firmware_high, firmware_entry);
if (firmware_low < FIRMWARE_START || firmware_high >= FIRMWARE_END) {
error_report("Firmware overlaps with memory or IO space");
exit(1);
}
g_free(firmware_filename);
rom_region = g_new(MemoryRegion, 1);
memory_region_init_ram(rom_region, NULL, "firmware",
(FIRMWARE_END - FIRMWARE_START), &error_fatal);
memory_region_add_subregion(addr_space, FIRMWARE_START, rom_region);
/* Load kernel */
if (kernel_filename) {
size = load_elf(kernel_filename, NULL, &cpu_hppa_to_phys,
NULL, &kernel_entry, &kernel_low, &kernel_high, NULL,
true, EM_PARISC, 0, 0);
/* Unfortunately, load_elf sign-extends reading elf32. */
kernel_entry = (target_ureg) cpu_hppa_to_phys(NULL, kernel_entry);
kernel_low = (target_ureg)kernel_low;
kernel_high = (target_ureg)kernel_high;
if (size < 0) {
error_report("could not load kernel '%s'", kernel_filename);
exit(1);
}
qemu_log_mask(CPU_LOG_PAGE, "Kernel loaded at 0x%08" PRIx64
"-0x%08" PRIx64 ", entry at 0x%08" PRIx64
", size %" PRIu64 " kB\n",
kernel_low, kernel_high, kernel_entry, size / KiB);
if (kernel_cmdline) {
cpu[0]->env.gr[24] = 0x4000;
pstrcpy_targphys("cmdline", cpu[0]->env.gr[24],
TARGET_PAGE_SIZE, kernel_cmdline);
}
if (initrd_filename) {
ram_addr_t initrd_base;
int64_t initrd_size;
initrd_size = get_image_size(initrd_filename);
if (initrd_size < 0) {
error_report("could not load initial ram disk '%s'",
initrd_filename);
exit(1);
}
/* Load the initrd image high in memory.
Mirror the algorithm used by palo:
(1) Due to sign-extension problems and PDC,
put the initrd no higher than 1G.
(2) Reserve 64k for stack. */
initrd_base = MIN(machine->ram_size, 1 * GiB);
initrd_base = initrd_base - 64 * KiB;
initrd_base = (initrd_base - initrd_size) & TARGET_PAGE_MASK;
if (initrd_base < kernel_high) {
error_report("kernel and initial ram disk too large!");
exit(1);
}
load_image_targphys(initrd_filename, initrd_base, initrd_size);
cpu[0]->env.gr[23] = initrd_base;
cpu[0]->env.gr[22] = initrd_base + initrd_size;
}
}
if (!kernel_entry) {
/* When booting via firmware, tell firmware if we want interactive
* mode (kernel_entry=1), and to boot from CD (gr[24]='d')
* or hard disc * (gr[24]='c').
*/
kernel_entry = boot_menu ? 1 : 0;
cpu[0]->env.gr[24] = machine->boot_order[0];
}
/* We jump to the firmware entry routine and pass the
* various parameters in registers. After firmware initialization,
* firmware will start the Linux kernel with ramdisk and cmdline.
*/
cpu[0]->env.gr[26] = machine->ram_size;
cpu[0]->env.gr[25] = kernel_entry;
/* tell firmware how many SMP CPUs to present in inventory table */
cpu[0]->env.gr[21] = smp_cpus;
/* tell firmware fw_cfg port */
cpu[0]->env.gr[19] = FW_CFG_IO_BASE;
}
static void hppa_machine_reset(MachineState *ms)
{
unsigned int smp_cpus = ms->smp.cpus;
int i;
qemu_devices_reset();
/* Start all CPUs at the firmware entry point.
* Monarch CPU will initialize firmware, secondary CPUs
* will enter a small idle look and wait for rendevouz. */
for (i = 0; i < smp_cpus; i++) {
cpu_set_pc(CPU(cpu[i]), firmware_entry);
cpu[i]->env.gr[5] = CPU_HPA + i * 0x1000;
}
/* already initialized by machine_hppa_init()? */
if (cpu[0]->env.gr[26] == ms->ram_size) {
return;
}
cpu[0]->env.gr[26] = ms->ram_size;
cpu[0]->env.gr[25] = 0; /* no firmware boot menu */
cpu[0]->env.gr[24] = 'c';
/* gr22/gr23 unused, no initrd while reboot. */
cpu[0]->env.gr[21] = smp_cpus;
/* tell firmware fw_cfg port */
cpu[0]->env.gr[19] = FW_CFG_IO_BASE;
}
static void hppa_nmi(NMIState *n, int cpu_index, Error **errp)
{
CPUState *cs;
CPU_FOREACH(cs) {
cpu_interrupt(cs, CPU_INTERRUPT_NMI);
}
}
static void machine_hppa_machine_init(MachineClass *mc)
{
mc->desc = "HPPA generic machine";
mc->default_cpu_type = TYPE_HPPA_CPU;
mc->init = machine_hppa_init;
mc->reset = hppa_machine_reset;
mc->block_default_type = IF_SCSI;
mc->max_cpus = HPPA_MAX_CPUS;
mc->default_cpus = 1;
mc->is_default = true;
mc->default_ram_size = 512 * MiB;
mc->default_boot_order = "cd";
mc->default_ram_id = "ram";
}
static void machine_hppa_machine_init_class_init(ObjectClass *oc, void *data)
{
MachineClass *mc = MACHINE_CLASS(oc);
machine_hppa_machine_init(mc);
NMIClass *nc = NMI_CLASS(oc);
nc->nmi_monitor_handler = hppa_nmi;
}
static const TypeInfo machine_hppa_machine_init_typeinfo = {
.name = ("hppa" "-machine"),
.parent = "machine",
.class_init = machine_hppa_machine_init_class_init,
.interfaces = (InterfaceInfo[]) {
{ TYPE_NMI },
{ }
},
};
static void machine_hppa_machine_init_register_types(void)
{
type_register_static(&machine_hppa_machine_init_typeinfo);
}
type_init(machine_hppa_machine_init_register_types)