xemu-project/xemu
1
0
Fork 0
mirror of https://github.com/xemu-project/xemu.git synced 2024-11-30 15:00:34 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
d6a9b0b89d
xemu/hw/ppc/ppc405_boards.c
Andreas Färber 8a661aea0e Revert use of DEFINE_MACHINE() for registrations of multiple machines 
The script used for converting from QEMUMachine had used one
DEFINE_MACHINE() per machine registered. In cases where multiple
machines are registered from one source file, avoid the excessive
generation of module init functions by reverting this unrolling.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2015-09-19 16:40:27 +02:00

697 lines
21 KiB
C
Raw Blame History

/*
* QEMU PowerPC 405 evaluation boards emulation
*
* Copyright (c) 2007 Jocelyn Mayer
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "hw/hw.h"
#include "hw/ppc/ppc.h"
#include "ppc405.h"
#include "hw/timer/m48t59.h"
#include "hw/block/flash.h"
#include "sysemu/sysemu.h"
#include "sysemu/qtest.h"
#include "sysemu/block-backend.h"
#include "hw/boards.h"
#include "qemu/log.h"
#include "qemu/error-report.h"
#include "hw/loader.h"
#include "sysemu/block-backend.h"
#include "sysemu/blockdev.h"
#include "exec/address-spaces.h"
#define BIOS_FILENAME "ppc405_rom.bin"
#define BIOS_SIZE (2048 * 1024)
#define KERNEL_LOAD_ADDR 0x00000000
#define INITRD_LOAD_ADDR 0x01800000
#define USE_FLASH_BIOS
//#define DEBUG_BOARD_INIT
/*****************************************************************************/
/* PPC405EP reference board (IBM) */
/* Standalone board with:
* - PowerPC 405EP CPU
* - SDRAM (0x00000000)
* - Flash (0xFFF80000)
* - SRAM (0xFFF00000)
* - NVRAM (0xF0000000)
* - FPGA (0xF0300000)
*/
typedef struct ref405ep_fpga_t ref405ep_fpga_t;
struct ref405ep_fpga_t {
uint8_t reg0;
uint8_t reg1;
};
static uint32_t ref405ep_fpga_readb (void *opaque, hwaddr addr)
{
ref405ep_fpga_t *fpga;
uint32_t ret;
fpga = opaque;
switch (addr) {
case 0x0:
ret = fpga->reg0;
break;
case 0x1:
ret = fpga->reg1;
break;
default:
ret = 0;
break;
}
return ret;
}
static void ref405ep_fpga_writeb (void *opaque,
hwaddr addr, uint32_t value)
{
ref405ep_fpga_t *fpga;
fpga = opaque;
switch (addr) {
case 0x0:
/* Read only */
break;
case 0x1:
fpga->reg1 = value;
break;
default:
break;
}
}
static uint32_t ref405ep_fpga_readw (void *opaque, hwaddr addr)
{
uint32_t ret;
ret = ref405ep_fpga_readb(opaque, addr) << 8;
ret |= ref405ep_fpga_readb(opaque, addr + 1);
return ret;
}
static void ref405ep_fpga_writew (void *opaque,
hwaddr addr, uint32_t value)
{
ref405ep_fpga_writeb(opaque, addr, (value >> 8) & 0xFF);
ref405ep_fpga_writeb(opaque, addr + 1, value & 0xFF);
}
static uint32_t ref405ep_fpga_readl (void *opaque, hwaddr addr)
{
uint32_t ret;
ret = ref405ep_fpga_readb(opaque, addr) << 24;
ret |= ref405ep_fpga_readb(opaque, addr + 1) << 16;
ret |= ref405ep_fpga_readb(opaque, addr + 2) << 8;
ret |= ref405ep_fpga_readb(opaque, addr + 3);
return ret;
}
static void ref405ep_fpga_writel (void *opaque,
hwaddr addr, uint32_t value)
{
ref405ep_fpga_writeb(opaque, addr, (value >> 24) & 0xFF);
ref405ep_fpga_writeb(opaque, addr + 1, (value >> 16) & 0xFF);
ref405ep_fpga_writeb(opaque, addr + 2, (value >> 8) & 0xFF);
ref405ep_fpga_writeb(opaque, addr + 3, value & 0xFF);
}
static const MemoryRegionOps ref405ep_fpga_ops = {
.old_mmio = {
.read = {
ref405ep_fpga_readb, ref405ep_fpga_readw, ref405ep_fpga_readl,
},
.write = {
ref405ep_fpga_writeb, ref405ep_fpga_writew, ref405ep_fpga_writel,
},
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void ref405ep_fpga_reset (void *opaque)
{
ref405ep_fpga_t *fpga;
fpga = opaque;
fpga->reg0 = 0x00;
fpga->reg1 = 0x0F;
}
static void ref405ep_fpga_init(MemoryRegion *sysmem, uint32_t base)
{
ref405ep_fpga_t *fpga;
MemoryRegion *fpga_memory = g_new(MemoryRegion, 1);
fpga = g_malloc0(sizeof(ref405ep_fpga_t));
memory_region_init_io(fpga_memory, NULL, &ref405ep_fpga_ops, fpga,
"fpga", 0x00000100);
memory_region_add_subregion(sysmem, base, fpga_memory);
qemu_register_reset(&ref405ep_fpga_reset, fpga);
}
static void ref405ep_init(MachineState *machine)
{
ram_addr_t ram_size = machine->ram_size;
const char *kernel_filename = machine->kernel_filename;
const char *kernel_cmdline = machine->kernel_cmdline;
const char *initrd_filename = machine->initrd_filename;
char *filename;
ppc4xx_bd_info_t bd;
CPUPPCState *env;
qemu_irq *pic;
MemoryRegion *bios;
MemoryRegion *sram = g_new(MemoryRegion, 1);
ram_addr_t bdloc;
MemoryRegion *ram_memories = g_malloc(2 * sizeof(*ram_memories));
hwaddr ram_bases[2], ram_sizes[2];
target_ulong sram_size;
long bios_size;
//int phy_addr = 0;
//static int phy_addr = 1;
target_ulong kernel_base, initrd_base;
long kernel_size, initrd_size;
int linux_boot;
int fl_idx, fl_sectors, len;
DriveInfo *dinfo;
MemoryRegion *sysmem = get_system_memory();
/* XXX: fix this */
memory_region_allocate_system_memory(&ram_memories[0], NULL, "ef405ep.ram",
0x08000000);
ram_bases[0] = 0;
ram_sizes[0] = 0x08000000;
memory_region_init(&ram_memories[1], NULL, "ef405ep.ram1", 0);
ram_bases[1] = 0x00000000;
ram_sizes[1] = 0x00000000;
ram_size = 128 * 1024 * 1024;
#ifdef DEBUG_BOARD_INIT
printf("%s: register cpu\n", __func__);
#endif
env = ppc405ep_init(sysmem, ram_memories, ram_bases, ram_sizes,
33333333, &pic, kernel_filename == NULL ? 0 : 1);
/* allocate SRAM */
sram_size = 512 * 1024;
memory_region_init_ram(sram, NULL, "ef405ep.sram", sram_size,
&error_fatal);
vmstate_register_ram_global(sram);
memory_region_add_subregion(sysmem, 0xFFF00000, sram);
/* allocate and load BIOS */
#ifdef DEBUG_BOARD_INIT
printf("%s: register BIOS\n", __func__);
#endif
fl_idx = 0;
#ifdef USE_FLASH_BIOS
dinfo = drive_get(IF_PFLASH, 0, fl_idx);
if (dinfo) {
BlockBackend *blk = blk_by_legacy_dinfo(dinfo);
bios_size = blk_getlength(blk);
fl_sectors = (bios_size + 65535) >> 16;
#ifdef DEBUG_BOARD_INIT
printf("Register parallel flash %d size %lx"
" at addr %lx '%s' %d\n",
fl_idx, bios_size, -bios_size,
blk_name(blk), fl_sectors);
#endif
pflash_cfi02_register((uint32_t)(-bios_size),
NULL, "ef405ep.bios", bios_size,
blk, 65536, fl_sectors, 1,
2, 0x0001, 0x22DA, 0x0000, 0x0000, 0x555, 0x2AA,
1);
fl_idx++;
} else
#endif
{
#ifdef DEBUG_BOARD_INIT
printf("Load BIOS from file\n");
#endif
bios = g_new(MemoryRegion, 1);
memory_region_init_ram(bios, NULL, "ef405ep.bios", BIOS_SIZE,
&error_fatal);
vmstate_register_ram_global(bios);
if (bios_name == NULL)
bios_name = BIOS_FILENAME;
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
if (filename) {
bios_size = load_image(filename, memory_region_get_ram_ptr(bios));
g_free(filename);
if (bios_size < 0 || bios_size > BIOS_SIZE) {
error_report("Could not load PowerPC BIOS '%s'", bios_name);
exit(1);
}
bios_size = (bios_size + 0xfff) & ~0xfff;
memory_region_add_subregion(sysmem, (uint32_t)(-bios_size), bios);
} else if (!qtest_enabled() || kernel_filename != NULL) {
error_report("Could not load PowerPC BIOS '%s'", bios_name);
exit(1);
} else {
/* Avoid an uninitialized variable warning */
bios_size = -1;
}
memory_region_set_readonly(bios, true);
}
/* Register FPGA */
#ifdef DEBUG_BOARD_INIT
printf("%s: register FPGA\n", __func__);
#endif
ref405ep_fpga_init(sysmem, 0xF0300000);
/* Register NVRAM */
#ifdef DEBUG_BOARD_INIT
printf("%s: register NVRAM\n", __func__);
#endif
m48t59_init(NULL, 0xF0000000, 0, 8192, 1968, 8);
/* Load kernel */
linux_boot = (kernel_filename != NULL);
if (linux_boot) {
#ifdef DEBUG_BOARD_INIT
printf("%s: load kernel\n", __func__);
#endif
memset(&bd, 0, sizeof(bd));
bd.bi_memstart = 0x00000000;
bd.bi_memsize = ram_size;
bd.bi_flashstart = -bios_size;
bd.bi_flashsize = -bios_size;
bd.bi_flashoffset = 0;
bd.bi_sramstart = 0xFFF00000;
bd.bi_sramsize = sram_size;
bd.bi_bootflags = 0;
bd.bi_intfreq = 133333333;
bd.bi_busfreq = 33333333;
bd.bi_baudrate = 115200;
bd.bi_s_version[0] = 'Q';
bd.bi_s_version[1] = 'M';
bd.bi_s_version[2] = 'U';
bd.bi_s_version[3] = '\0';
bd.bi_r_version[0] = 'Q';
bd.bi_r_version[1] = 'E';
bd.bi_r_version[2] = 'M';
bd.bi_r_version[3] = 'U';
bd.bi_r_version[4] = '\0';
bd.bi_procfreq = 133333333;
bd.bi_plb_busfreq = 33333333;
bd.bi_pci_busfreq = 33333333;
bd.bi_opbfreq = 33333333;
bdloc = ppc405_set_bootinfo(env, &bd, 0x00000001);
env->gpr[3] = bdloc;
kernel_base = KERNEL_LOAD_ADDR;
/* now we can load the kernel */
kernel_size = load_image_targphys(kernel_filename, kernel_base,
ram_size - kernel_base);
if (kernel_size < 0) {
fprintf(stderr, "qemu: could not load kernel '%s'\n",
kernel_filename);
exit(1);
}
printf("Load kernel size %ld at " TARGET_FMT_lx,
kernel_size, kernel_base);
/* load initrd */
if (initrd_filename) {
initrd_base = INITRD_LOAD_ADDR;
initrd_size = load_image_targphys(initrd_filename, initrd_base,
ram_size - initrd_base);
if (initrd_size < 0) {
fprintf(stderr, "qemu: could not load initial ram disk '%s'\n",
initrd_filename);
exit(1);
}
} else {
initrd_base = 0;
initrd_size = 0;
}
env->gpr[4] = initrd_base;
env->gpr[5] = initrd_size;
if (kernel_cmdline != NULL) {
len = strlen(kernel_cmdline);
bdloc -= ((len + 255) & ~255);
cpu_physical_memory_write(bdloc, kernel_cmdline, len + 1);
env->gpr[6] = bdloc;
env->gpr[7] = bdloc + len;
} else {
env->gpr[6] = 0;
env->gpr[7] = 0;
}
env->nip = KERNEL_LOAD_ADDR;
} else {
kernel_base = 0;
kernel_size = 0;
initrd_base = 0;
initrd_size = 0;
bdloc = 0;
}
#ifdef DEBUG_BOARD_INIT
printf("bdloc " RAM_ADDR_FMT "\n", bdloc);
printf("%s: Done\n", __func__);
#endif
}
static void ref405ep_class_init(ObjectClass *oc, void *data)
{
MachineClass *mc = MACHINE_CLASS(oc);
mc->desc = "ref405ep";
mc->init = ref405ep_init;
}
static const TypeInfo ref405ep_type = {
.name = MACHINE_TYPE_NAME("ref405ep"),
.parent = TYPE_MACHINE,
.class_init = ref405ep_class_init,
};
/*****************************************************************************/
/* AMCC Taihu evaluation board */
/* - PowerPC 405EP processor
* - SDRAM 128 MB at 0x00000000
* - Boot flash 2 MB at 0xFFE00000
* - Application flash 32 MB at 0xFC000000
* - 2 serial ports
* - 2 ethernet PHY
* - 1 USB 1.1 device 0x50000000
* - 1 LCD display 0x50100000
* - 1 CPLD 0x50100000
* - 1 I2C EEPROM
* - 1 I2C thermal sensor
* - a set of LEDs
* - bit-bang SPI port using GPIOs
* - 1 EBC interface connector 0 0x50200000
* - 1 cardbus controller + expansion slot.
* - 1 PCI expansion slot.
*/
typedef struct taihu_cpld_t taihu_cpld_t;
struct taihu_cpld_t {
uint8_t reg0;
uint8_t reg1;
};
static uint32_t taihu_cpld_readb (void *opaque, hwaddr addr)
{
taihu_cpld_t *cpld;
uint32_t ret;
cpld = opaque;
switch (addr) {
case 0x0:
ret = cpld->reg0;
break;
case 0x1:
ret = cpld->reg1;
break;
default:
ret = 0;
break;
}
return ret;
}
static void taihu_cpld_writeb (void *opaque,
hwaddr addr, uint32_t value)
{
taihu_cpld_t *cpld;
cpld = opaque;
switch (addr) {
case 0x0:
/* Read only */
break;
case 0x1:
cpld->reg1 = value;
break;
default:
break;
}
}
static uint32_t taihu_cpld_readw (void *opaque, hwaddr addr)
{
uint32_t ret;
ret = taihu_cpld_readb(opaque, addr) << 8;
ret |= taihu_cpld_readb(opaque, addr + 1);
return ret;
}
static void taihu_cpld_writew (void *opaque,
hwaddr addr, uint32_t value)
{
taihu_cpld_writeb(opaque, addr, (value >> 8) & 0xFF);
taihu_cpld_writeb(opaque, addr + 1, value & 0xFF);
}
static uint32_t taihu_cpld_readl (void *opaque, hwaddr addr)
{
uint32_t ret;
ret = taihu_cpld_readb(opaque, addr) << 24;
ret |= taihu_cpld_readb(opaque, addr + 1) << 16;
ret |= taihu_cpld_readb(opaque, addr + 2) << 8;
ret |= taihu_cpld_readb(opaque, addr + 3);
return ret;
}
static void taihu_cpld_writel (void *opaque,
hwaddr addr, uint32_t value)
{
taihu_cpld_writel(opaque, addr, (value >> 24) & 0xFF);
taihu_cpld_writel(opaque, addr + 1, (value >> 16) & 0xFF);
taihu_cpld_writel(opaque, addr + 2, (value >> 8) & 0xFF);
taihu_cpld_writeb(opaque, addr + 3, value & 0xFF);
}
static const MemoryRegionOps taihu_cpld_ops = {
.old_mmio = {
.read = { taihu_cpld_readb, taihu_cpld_readw, taihu_cpld_readl, },
.write = { taihu_cpld_writeb, taihu_cpld_writew, taihu_cpld_writel, },
},
.endianness = DEVICE_NATIVE_ENDIAN,
};
static void taihu_cpld_reset (void *opaque)
{
taihu_cpld_t *cpld;
cpld = opaque;
cpld->reg0 = 0x01;
cpld->reg1 = 0x80;
}
static void taihu_cpld_init(MemoryRegion *sysmem, uint32_t base)
{
taihu_cpld_t *cpld;
MemoryRegion *cpld_memory = g_new(MemoryRegion, 1);
cpld = g_malloc0(sizeof(taihu_cpld_t));
memory_region_init_io(cpld_memory, NULL, &taihu_cpld_ops, cpld, "cpld", 0x100);
memory_region_add_subregion(sysmem, base, cpld_memory);
qemu_register_reset(&taihu_cpld_reset, cpld);
}
static void taihu_405ep_init(MachineState *machine)
{
ram_addr_t ram_size = machine->ram_size;
const char *kernel_filename = machine->kernel_filename;
const char *initrd_filename = machine->initrd_filename;
char *filename;
qemu_irq *pic;
MemoryRegion *sysmem = get_system_memory();
MemoryRegion *bios;
MemoryRegion *ram_memories = g_malloc(2 * sizeof(*ram_memories));
MemoryRegion *ram = g_malloc0(sizeof(*ram));
hwaddr ram_bases[2], ram_sizes[2];
long bios_size;
target_ulong kernel_base, initrd_base;
long kernel_size, initrd_size;
int linux_boot;
int fl_idx, fl_sectors;
DriveInfo *dinfo;
/* RAM is soldered to the board so the size cannot be changed */
ram_size = 0x08000000;
memory_region_allocate_system_memory(ram, NULL, "taihu_405ep.ram",
ram_size);
ram_bases[0] = 0;
ram_sizes[0] = 0x04000000;
memory_region_init_alias(&ram_memories[0], NULL,
"taihu_405ep.ram-0", ram, ram_bases[0],
ram_sizes[0]);
ram_bases[1] = 0x04000000;
ram_sizes[1] = 0x04000000;
memory_region_init_alias(&ram_memories[1], NULL,
"taihu_405ep.ram-1", ram, ram_bases[1],
ram_sizes[1]);
#ifdef DEBUG_BOARD_INIT
printf("%s: register cpu\n", __func__);
#endif
ppc405ep_init(sysmem, ram_memories, ram_bases, ram_sizes,
33333333, &pic, kernel_filename == NULL ? 0 : 1);
/* allocate and load BIOS */
#ifdef DEBUG_BOARD_INIT
printf("%s: register BIOS\n", __func__);
#endif
fl_idx = 0;
#if defined(USE_FLASH_BIOS)
dinfo = drive_get(IF_PFLASH, 0, fl_idx);
if (dinfo) {
BlockBackend *blk = blk_by_legacy_dinfo(dinfo);
bios_size = blk_getlength(blk);
/* XXX: should check that size is 2MB */
// bios_size = 2 * 1024 * 1024;
fl_sectors = (bios_size + 65535) >> 16;
#ifdef DEBUG_BOARD_INIT
printf("Register parallel flash %d size %lx"
" at addr %lx '%s' %d\n",
fl_idx, bios_size, -bios_size,
blk_name(blk), fl_sectors);
#endif
pflash_cfi02_register((uint32_t)(-bios_size),
NULL, "taihu_405ep.bios", bios_size,
blk, 65536, fl_sectors, 1,
4, 0x0001, 0x22DA, 0x0000, 0x0000, 0x555, 0x2AA,
1);
fl_idx++;
} else
#endif
{
#ifdef DEBUG_BOARD_INIT
printf("Load BIOS from file\n");
#endif
if (bios_name == NULL)
bios_name = BIOS_FILENAME;
bios = g_new(MemoryRegion, 1);
memory_region_init_ram(bios, NULL, "taihu_405ep.bios", BIOS_SIZE,
&error_fatal);
vmstate_register_ram_global(bios);
filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
if (filename) {
bios_size = load_image(filename, memory_region_get_ram_ptr(bios));
g_free(filename);
if (bios_size < 0 || bios_size > BIOS_SIZE) {
error_report("Could not load PowerPC BIOS '%s'", bios_name);
exit(1);
}
bios_size = (bios_size + 0xfff) & ~0xfff;
memory_region_add_subregion(sysmem, (uint32_t)(-bios_size), bios);
} else if (!qtest_enabled()) {
error_report("Could not load PowerPC BIOS '%s'", bios_name);
exit(1);
}
memory_region_set_readonly(bios, true);
}
/* Register Linux flash */
dinfo = drive_get(IF_PFLASH, 0, fl_idx);
if (dinfo) {
BlockBackend *blk = blk_by_legacy_dinfo(dinfo);
bios_size = blk_getlength(blk);
/* XXX: should check that size is 32MB */
bios_size = 32 * 1024 * 1024;
fl_sectors = (bios_size + 65535) >> 16;
#ifdef DEBUG_BOARD_INIT
printf("Register parallel flash %d size %lx"
" at addr " TARGET_FMT_lx " '%s'\n",
fl_idx, bios_size, (target_ulong)0xfc000000,
blk_name(blk));
#endif
pflash_cfi02_register(0xfc000000, NULL, "taihu_405ep.flash", bios_size,
blk, 65536, fl_sectors, 1,
4, 0x0001, 0x22DA, 0x0000, 0x0000, 0x555, 0x2AA,
1);
fl_idx++;
}
/* Register CLPD & LCD display */
#ifdef DEBUG_BOARD_INIT
printf("%s: register CPLD\n", __func__);
#endif
taihu_cpld_init(sysmem, 0x50100000);
/* Load kernel */
linux_boot = (kernel_filename != NULL);
if (linux_boot) {
#ifdef DEBUG_BOARD_INIT
printf("%s: load kernel\n", __func__);
#endif
kernel_base = KERNEL_LOAD_ADDR;
/* now we can load the kernel */
kernel_size = load_image_targphys(kernel_filename, kernel_base,
ram_size - kernel_base);
if (kernel_size < 0) {
fprintf(stderr, "qemu: could not load kernel '%s'\n",
kernel_filename);
exit(1);
}
/* load initrd */
if (initrd_filename) {
initrd_base = INITRD_LOAD_ADDR;
initrd_size = load_image_targphys(initrd_filename, initrd_base,
ram_size - initrd_base);
if (initrd_size < 0) {
fprintf(stderr,
"qemu: could not load initial ram disk '%s'\n",
initrd_filename);
exit(1);
}
} else {
initrd_base = 0;
initrd_size = 0;
}
} else {
kernel_base = 0;
kernel_size = 0;
initrd_base = 0;
initrd_size = 0;
}
#ifdef DEBUG_BOARD_INIT
printf("%s: Done\n", __func__);
#endif
}
static void taihu_class_init(ObjectClass *oc, void *data)
{
MachineClass *mc = MACHINE_CLASS(oc);
mc->desc = "taihu";
mc->init = taihu_405ep_init;
}
static const TypeInfo taihu_type = {
.name = MACHINE_TYPE_NAME("taihu"),
.parent = TYPE_MACHINE,
.class_init = taihu_class_init,
};
static void ppc405_machine_init(void)
{
type_register_static(&ref405ep_type);
type_register_static(&taihu_type);
}
machine_init(ppc405_machine_init)
Reference in New Issue View Git Blame Copy Permalink