u-boot/board/sc520_spunk/sc520_spunk.c

678 lines
19 KiB
C
Raw Normal View History

/*
*
* (C) Copyright 2002
* Daniel Engstr<EFBFBD>m, Omicron Ceti AB <daniel@omicron.se>.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <pci.h>
#include <ssi.h>
#include <asm/io.h>
#include <asm/pci.h>
#include <asm/ic/sc520.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* Theory:
* We first set up all IRQs to be non-pci, edge triggered,
* when we later enumerate the pci bus and pci_sc520_fixup_irq() gets
* called we reallocate irqs to the pci bus with sc520_pci_set_irq()
* as needed. Whe choose the irqs to gram from a configurable list
* inside pci_sc520_fixup_irq() (If this list contains stupid irq's
* such as 0 thngas will not work)
*/
static void irq_init(void)
{
/* disable global interrupt mode */
write_mmcr_byte(SC520_PICICR, 0x40);
/* set all irqs to edge */
write_mmcr_byte(SC520_MPICMODE, 0x00);
write_mmcr_byte(SC520_SL1PICMODE, 0x00);
write_mmcr_byte(SC520_SL2PICMODE, 0x00);
/* active low polarity on PIC interrupt pins,
* active high polarity on all other irq pins */
write_mmcr_word(SC520_INTPINPOL, 0x0000);
/* set irq number mapping */
write_mmcr_byte(SC520_GPTMR0MAP, SC520_IRQ_DISABLED); /* disable GP timer 0 INT */
write_mmcr_byte(SC520_GPTMR1MAP, SC520_IRQ_DISABLED); /* disable GP timer 1 INT */
write_mmcr_byte(SC520_GPTMR2MAP, SC520_IRQ_DISABLED); /* disable GP timer 2 INT */
write_mmcr_byte(SC520_PIT0MAP, SC520_IRQ0); /* Set PIT timer 0 INT to IRQ0 */
write_mmcr_byte(SC520_PIT1MAP, SC520_IRQ_DISABLED); /* disable PIT timer 1 INT */
write_mmcr_byte(SC520_PIT2MAP, SC520_IRQ_DISABLED); /* disable PIT timer 2 INT */
write_mmcr_byte(SC520_PCIINTAMAP, SC520_IRQ_DISABLED); /* disable PCI INT A */
write_mmcr_byte(SC520_PCIINTBMAP, SC520_IRQ_DISABLED); /* disable PCI INT B */
write_mmcr_byte(SC520_PCIINTCMAP, SC520_IRQ_DISABLED); /* disable PCI INT C */
write_mmcr_byte(SC520_PCIINTDMAP, SC520_IRQ_DISABLED); /* disable PCI INT D */
write_mmcr_byte(SC520_DMABCINTMAP, SC520_IRQ_DISABLED); /* disable DMA INT */
write_mmcr_byte(SC520_SSIMAP, SC520_IRQ6); /* Set Synchronius serial INT to IRQ6*/
write_mmcr_byte(SC520_WDTMAP, SC520_IRQ_DISABLED); /* disable Watchdog INT */
write_mmcr_byte(SC520_RTCMAP, SC520_IRQ8); /* Set RTC int to 8 */
write_mmcr_byte(SC520_WPVMAP, SC520_IRQ_DISABLED); /* disable write protect INT */
write_mmcr_byte(SC520_ICEMAP, SC520_IRQ1); /* Set ICE Debug Serielport INT to IRQ1 */
write_mmcr_byte(SC520_FERRMAP,SC520_IRQ13); /* Set FP error INT to IRQ13 */
write_mmcr_byte(SC520_UART1MAP, SC520_IRQ4); /* Set internal UART2 INT to IRQ4 */
write_mmcr_byte(SC520_UART2MAP, SC520_IRQ3); /* Set internal UART2 INT to IRQ3 */
write_mmcr_byte(SC520_GP0IMAP, SC520_IRQ7); /* Set GPIRQ0 (PC-Card AUX IRQ) to IRQ7 */
write_mmcr_byte(SC520_GP1IMAP, SC520_IRQ14); /* Set GPIRQ1 (CF IRQ) to IRQ14 */
write_mmcr_byte(SC520_GP3IMAP, SC520_IRQ5); /* Set GPIRQ3 ( CAN IRQ ) ti IRQ5 */
write_mmcr_byte(SC520_GP4IMAP, SC520_IRQ_DISABLED); /* disbale GIRQ4 ( IRR IRQ ) */
write_mmcr_byte(SC520_GP5IMAP, SC520_IRQ_DISABLED); /* disable GPIRQ5 */
write_mmcr_byte(SC520_GP6IMAP, SC520_IRQ_DISABLED); /* disable GPIRQ6 */
write_mmcr_byte(SC520_GP7IMAP, SC520_IRQ_DISABLED); /* disable GPIRQ7 */
write_mmcr_byte(SC520_GP8IMAP, SC520_IRQ_DISABLED); /* disable GPIRQ8 */
write_mmcr_byte(SC520_GP9IMAP, SC520_IRQ_DISABLED); /* disable GPIRQ9 */
write_mmcr_byte(SC520_GP2IMAP, SC520_IRQ_DISABLED); /* disable GPIRQ2 */
write_mmcr_byte(SC520_GP10IMAP,SC520_IRQ_DISABLED); /* disable GPIRQ10 */
write_mmcr_word(SC520_PCIHOSTMAP, 0x11f); /* Map PCI hostbridge INT to NMI */
write_mmcr_word(SC520_ECCMAP, 0x100); /* Map SDRAM ECC failure INT to NMI */
}
/* PCI stuff */
static void pci_sc520_spunk_fixup_irq(struct pci_controller *hose, pci_dev_t dev)
{
int version = read_mmcr_byte(SC520_SYSINFO);
/* a configurable lists of irqs to steal
* when we need one (a board with more pci interrupt pins
* would use a larger table */
static int irq_list[] = {
CFG_FIRST_PCI_IRQ,
CFG_SECOND_PCI_IRQ,
CFG_THIRD_PCI_IRQ,
CFG_FORTH_PCI_IRQ
};
static int next_irq_index=0;
char tmp_pin;
int pin;
pci_hose_read_config_byte(hose, dev, PCI_INTERRUPT_PIN, &tmp_pin);
pin = tmp_pin;
pin-=1; /* pci config space use 1-based numbering */
if (-1 == pin) {
return; /* device use no irq */
}
/* map device number + pin to a pin on the sc520 */
switch (PCI_DEV(dev)) {
case 6: /* ETH0 */
pin+=SC520_PCI_INTA;
break;
case 7: /* ETH1 */
pin+=SC520_PCI_INTB;
break;
case 8: /* Crypto */
pin+=SC520_PCI_INTC;
break;
case 9: /* PMC slot */
pin+=SC520_PCI_INTD;
break;
case 10: /* PC-Card */
if (version < 10) {
pin+=SC520_PCI_INTD;
} else {
pin+=SC520_PCI_INTC;
}
break;
default:
return;
}
pin&=3; /* wrap around */
if (sc520_pci_ints[pin] == -1) {
/* re-route one interrupt for us */
if (next_irq_index > 3) {
return;
}
if (pci_sc520_set_irq(pin, irq_list[next_irq_index])) {
return;
}
next_irq_index++;
}
if (-1 != sc520_pci_ints[pin]) {
pci_hose_write_config_byte(hose, dev, PCI_INTERRUPT_LINE,
sc520_pci_ints[pin]);
}
#if 0
printf("fixup_irq: device %d pin %c irq %d\n",
PCI_DEV(dev), 'A' + pin, sc520_pci_ints[pin]);
#endif
}
static void pci_sc520_spunk_configure_cardbus(struct pci_controller *hose,
pci_dev_t dev, struct pci_config_table *te)
{
u32 io_base;
u32 temp;
pciauto_config_device(hose, dev);
pci_hose_write_config_word(hose, dev, PCI_COMMAND, 0x07); /* enable device */
pci_hose_write_config_byte(hose, dev, 0x0c, 0x10); /* cacheline size */
pci_hose_write_config_byte(hose, dev, 0x0d, 0x40); /* latency timer */
pci_hose_write_config_byte(hose, dev, 0x1b, 0x40); /* cardbus latency timer */
pci_hose_write_config_word(hose, dev, PCI_BRIDGE_CONTROL, 0x0040); /* reset cardbus */
pci_hose_write_config_word(hose, dev, PCI_BRIDGE_CONTROL, 0x0080); /* route interrupts though ExCA */
pci_hose_write_config_word(hose, dev, 0x44, 0x3e0); /* map legacy I/O port to 0x3e0 */
pci_hose_read_config_dword(hose, dev, 0x80, &temp); /* System control */
pci_hose_write_config_dword(hose, dev, 0x80, temp | 0x60); /* System control: disable clockrun */
/* route MF0 to ~INT and MF3 to IRQ7
* reserve all others */
pci_hose_write_config_dword(hose, dev, 0x8c, 0x00007002);
pci_hose_write_config_byte(hose, dev, 0x91, 0x00); /* card control */
pci_hose_write_config_byte(hose, dev, 0x92, 0x62); /* device control */
if (te->device != 0xac56) {
pci_hose_write_config_byte(hose, dev, 0x93, 0x21); /* async interrupt enable */
pci_hose_write_config_word(hose, dev, 0xa8, 0x0000); /* reset GPIO */
pci_hose_write_config_word(hose, dev, 0xac, 0x0000); /* reset GPIO */
pci_hose_write_config_word(hose, dev, 0xaa, 0x0000); /* reset GPIO */
pci_hose_write_config_word(hose, dev, 0xae, 0x0000); /* reset GPIO */
} else {
pci_hose_write_config_byte(hose, dev, 0x93, 0x20); /* */
}
pci_hose_write_config_word(hose, dev, 0xa4, 0x8000); /* reset power management */
pci_hose_read_config_dword(hose, dev, PCI_BASE_ADDRESS_0, &io_base);
io_base &= ~0xfL;
writeb(0x07, io_base+0x803); /* route CSC irq though ExCA and enable IRQ7 */
writel(0, io_base+0x10); /* CLKRUN default */
writel(0, io_base+0x20); /* CLKRUN default */
}
static struct pci_config_table pci_sc520_spunk_config_table[] = {
{ 0x104c, 0xac50, PCI_ANY_ID, 0, 0x0a, 0, pci_sc520_spunk_configure_cardbus, { 0, 0, 0} },
{ 0x104c, 0xac56, PCI_ANY_ID, 0, 0x0a, 0, pci_sc520_spunk_configure_cardbus, { 0, 0, 0} },
{ 0, 0, 0, 0, 0, 0, NULL, {0,0,0}}
};
static struct pci_controller sc520_spunk_hose = {
fixup_irq: pci_sc520_spunk_fixup_irq,
config_table: pci_sc520_spunk_config_table,
first_busno: 0x00,
last_busno: 0xff,
};
void pci_init_board(void)
{
pci_sc520_init(&sc520_spunk_hose);
}
/* set up the ISA bus timing and system address mappings */
static void bus_init(void)
{
/* versions
* 0 Hyglo versions 0.95 and 0.96 (large baords)
* ?? Hyglo version 0.97 (small board)
* 10 Spunk board
*/
int version = read_mmcr_byte(SC520_SYSINFO);
if (version) {
/* set up the GP IO pins (for the Spunk board) */
write_mmcr_word(SC520_PIOPFS31_16, 0xfff0); /* set the GPIO pin function 31-16 reg */
write_mmcr_word(SC520_PIOPFS15_0, 0x000f); /* set the GPIO pin function 15-0 reg */
write_mmcr_word(SC520_PIODIR31_16, 0x000f); /* set the GPIO direction 31-16 reg */
write_mmcr_word(SC520_PIODIR15_0, 0x1ff0); /* set the GPIO direction 15-0 reg */
write_mmcr_byte(SC520_CSPFS, 0xc0); /* set the CS pin function reg */
write_mmcr_byte(SC520_CLKSEL, 0x70);
write_mmcr_word(SC520_PIOCLR31_16, 0x0003); /* reset SSI chip-selects */
write_mmcr_word(SC520_PIOSET31_16, 0x000c);
} else {
/* set up the GP IO pins (for the Hyglo board) */
write_mmcr_word(SC520_PIOPFS31_16, 0xffc0); /* set the GPIO pin function 31-16 reg */
write_mmcr_word(SC520_PIOPFS15_0, 0x1e7f); /* set the GPIO pin function 15-0 reg */
write_mmcr_word(SC520_PIODIR31_16, 0x003f); /* set the GPIO direction 31-16 reg */
write_mmcr_word(SC520_PIODIR15_0, 0xe180); /* set the GPIO direction 15-0 reg */
write_mmcr_byte(SC520_CSPFS, 0x00); /* set the CS pin function reg */
write_mmcr_byte(SC520_CLKSEL, 0x70);
write_mmcr_word(SC520_PIOCLR15_0, 0x0180); /* reset SSI chip-selects */
}
write_mmcr_byte(SC520_GPCSRT, 1); /* set the GP CS offset */
write_mmcr_byte(SC520_GPCSPW, 3); /* set the GP CS pulse width */
write_mmcr_byte(SC520_GPCSOFF, 1); /* set the GP CS offset */
write_mmcr_byte(SC520_GPRDW, 3); /* set the RD pulse width */
write_mmcr_byte(SC520_GPRDOFF, 1); /* set the GP RD offset */
write_mmcr_byte(SC520_GPWRW, 3); /* set the GP WR pulse width */
write_mmcr_byte(SC520_GPWROFF, 1); /* set the GP WR offset */
write_mmcr_word(SC520_BOOTCSCTL, 0x0407); /* set up timing of BOOTCS */
/* adjust the memory map:
* by default the first 256MB (0x00000000 - 0x0fffffff) is mapped to SDRAM
* and 256MB to 1G-128k (0x1000000 - 0x37ffffff) is mapped to PCI mmio
* we need to map 1G-128k - 1G (0x38000000 - 0x3fffffff) to CS1 */
/* bootcs */
write_mmcr_long(SC520_PAR12, 0x8bffe800);
/* IDE0 = GPCS6 1f0-1f7 */
write_mmcr_long(SC520_PAR3, 0x380801f0);
/* IDE1 = GPCS7 3f6 */
write_mmcr_long(SC520_PAR4, 0x3c0003f6);
asm ("wbinvd\n"); /* Flush cache, req. after setting the unchached attribute ona PAR */
write_mmcr_byte(SC520_ADDDECCTL, read_mmcr_byte(SC520_ADDDECCTL) & ~(UART2_DIS|UART1_DIS));
}
/* par usage:
* PAR0 (legacy_video)
* PAR1 (PCI ROM mapping)
* PAR2
* PAR3 IDE
* PAR4 IDE
* PAR5 (legacy_video)
* PAR6
* PAR7 (legacy_video)
* PAR8 (legacy_video)
* PAR9 (legacy_video)
* PAR10
* PAR11 (ISAROM)
* PAR12 BOOTCS
* PAR13
* PAR14
* PAR15
*/
/*
* This function should map a chunk of size bytes
* of the system address space to the ISA bus
*
* The function will return the memory address
* as seen by the host (which may very will be the
* same as the bus address)
*/
u32 isa_map_rom(u32 bus_addr, int size)
{
u32 par;
printf("isa_map_rom asked to map %d bytes at %x\n",
size, bus_addr);
par = size;
if (par < 0x80000) {
par = 0x80000;
}
par >>= 12;
par--;
par&=0x7f;
par <<= 18;
par |= (bus_addr>>12);
par |= 0x50000000;
printf ("setting PAR11 to %x\n", par);
/* Map rom 0x10000 with PAR1 */
write_mmcr_long(SC520_PAR11, par);
return bus_addr;
}
/*
* this function removed any mapping created
* with pci_get_rom_window()
*/
void isa_unmap_rom(u32 addr)
{
printf("isa_unmap_rom asked to unmap %x", addr);
if ((addr>>12) == (read_mmcr_long(SC520_PAR11)&0x3ffff)) {
write_mmcr_long(SC520_PAR11, 0);
printf(" done\n");
return;
}
printf(" not ours\n");
}
#ifdef CONFIG_PCI
#define PCI_ROM_TEMP_SPACE 0x10000
/*
* This function should map a chunk of size bytes
* of the system address space to the PCI bus,
* suitable to map PCI ROMS (bus address < 16M)
* the function will return the host memory address
* which should be converted into a bus address
* before used to configure the PCI rom address
* decoder
*/
u32 pci_get_rom_window(struct pci_controller *hose, int size)
{
u32 par;
par = size;
if (par < 0x80000) {
par = 0x80000;
}
par >>= 16;
par--;
par&=0x7ff;
par <<= 14;
par |= (PCI_ROM_TEMP_SPACE>>16);
par |= 0x72000000;
printf ("setting PAR1 to %x\n", par);
/* Map rom 0x10000 with PAR1 */
write_mmcr_long(SC520_PAR1, par);
return PCI_ROM_TEMP_SPACE;
}
/*
* this function removed any mapping created
* with pci_get_rom_window()
*/
void pci_remove_rom_window(struct pci_controller *hose, u32 addr)
{
printf("pci_remove_rom_window: %x", addr);
if (addr == PCI_ROM_TEMP_SPACE) {
write_mmcr_long(SC520_PAR1, 0);
printf(" done\n");
return;
}
printf(" not ours\n");
}
/*
* This function is called in order to provide acces to the
* legacy video I/O ports on the PCI bus.
* After this function accesses to I/O ports 0x3b0-0x3bb and
* 0x3c0-0x3df shuld result in transactions on the PCI bus.
*
*/
int pci_enable_legacy_video_ports(struct pci_controller *hose)
{
/* Map video memory to 0xa0000*/
write_mmcr_long(SC520_PAR0, 0x7200400a);
/* forward all I/O accesses to PCI */
write_mmcr_byte(SC520_ADDDECCTL,
read_mmcr_byte(SC520_ADDDECCTL) | IO_HOLE_DEST_PCI);
/* so we map away all io ports to pci (only way to access pci io
* below 0x400. But then we have to map back the portions that we dont
* use so that the generate cycles on the GPIO bus where the sio and
* ISA slots are connected, this requre the use of several PAR registers
*/
/* bring 0x100 - 0x2f7 back to ISA using PAR5 */
write_mmcr_long(SC520_PAR5, 0x31f70100);
/* com2 use 2f8-2ff */
/* bring 0x300 - 0x3af back to ISA using PAR7 */
write_mmcr_long(SC520_PAR7, 0x30af0300);
/* vga use 3b0-3bb */
/* bring 0x3bc - 0x3bf back to ISA using PAR8 */
write_mmcr_long(SC520_PAR8, 0x300303bc);
/* vga use 3c0-3df */
/* bring 0x3e0 - 0x3f7 back to ISA using PAR9 */
write_mmcr_long(SC520_PAR9, 0x301703e0);
/* com1 use 3f8-3ff */
return 0;
}
#endif
/*
* Miscelaneous platform dependent initialisations
*/
int board_init(void)
{
init_sc520();
bus_init();
irq_init();
/* max drive current on SDRAM */
write_mmcr_word(SC520_DSCTL, 0x0100);
/* enter debug mode after next reset (only if jumper is also set) */
write_mmcr_byte(SC520_RESCFG, 0x08);
/* configure the software timer to 33.000MHz */
write_mmcr_byte(SC520_SWTMRCFG, 1);
gd->bus_clk = 33000000;
return 0;
}
int dram_init(void)
{
init_sc520_dram();
return 0;
}
void show_boot_progress(int val)
{
int version = read_mmcr_byte(SC520_SYSINFO);
if (version == 0) {
/* PIO31-PIO16 Data */
write_mmcr_word(SC520_PIODATA31_16,
(read_mmcr_word(SC520_PIODATA31_16) & 0xffc0)| ((val&0x7e)>>1)); /* 0x1f8 >> 3 */
/* PIO0-PIO15 Data */
write_mmcr_word(SC520_PIODATA15_0,
(read_mmcr_word(SC520_PIODATA15_0) & 0x1fff)| ((val&0x7)<<13));
} else {
/* newer boards use PIO4-PIO12 */
/* PIO0-PIO15 Data */
#if 0
val = (val & 0x007) | ((val & 0x038) << 3) | ((val & 0x1c0) >> 3);
#else
val = (val & 0x007) | ((val & 0x07e) << 2);
#endif
write_mmcr_word(SC520_PIODATA15_0,
(read_mmcr_word(SC520_PIODATA15_0) & 0xe00f) | ((val&0x01ff)<<4));
}
}
int last_stage_init(void)
{
int version = read_mmcr_byte(SC520_SYSINFO);
printf("Omicron Ceti SC520 Spunk revision %x\n", version);
#if 0
if (version) {
int x, y;
printf("eeprom probe %d\n", spi_eeprom_probe(1));
spi_eeprom_read(1, 0, (u8*)&x, 2);
spi_eeprom_read(1, 1, (u8*)&y, 2);
printf("eeprom bytes %04x%04x\n", x, y);
x ^= 0xffff;
y ^= 0xffff;
spi_eeprom_write(1, 0, (u8*)&x, 2);
spi_eeprom_write(1, 1, (u8*)&y, 2);
spi_eeprom_read(1, 0, (u8*)&x, 2);
spi_eeprom_read(1, 1, (u8*)&y, 2);
printf("eeprom bytes %04x%04x\n", x, y);
} else {
int x, y;
printf("eeprom probe %d\n", mw_eeprom_probe(1));
mw_eeprom_read(1, 0, (u8*)&x, 2);
mw_eeprom_read(1, 1, (u8*)&y, 2);
printf("eeprom bytes %04x%04x\n", x, y);
x ^= 0xffff;
y ^= 0xffff;
mw_eeprom_write(1, 0, (u8*)&x, 2);
mw_eeprom_write(1, 1, (u8*)&y, 2);
mw_eeprom_read(1, 0, (u8*)&x, 2);
mw_eeprom_read(1, 1, (u8*)&y, 2);
printf("eeprom bytes %04x%04x\n", x, y);
}
#endif
ds1722_probe(2);
return 0;
}
void ssi_chip_select(int dev)
{
int version = read_mmcr_byte(SC520_SYSINFO);
if (version) {
/* Spunk board: EEPROM and CAN are actove-low, TEMP and AUX are active high */
switch (dev) {
case 1: /* EEPROM */
write_mmcr_word(SC520_PIOCLR31_16, 0x0004);
break;
case 2: /* Temp Probe */
write_mmcr_word(SC520_PIOSET31_16, 0x0002);
break;
case 3: /* CAN */
write_mmcr_word(SC520_PIOCLR31_16, 0x0008);
break;
case 4: /* AUX */
write_mmcr_word(SC520_PIOSET31_16, 0x0001);
break;
case 0:
write_mmcr_word(SC520_PIOCLR31_16, 0x0003);
write_mmcr_word(SC520_PIOSET31_16, 0x000c);
break;
default:
printf("Illegal SSI device requested: %d\n", dev);
}
} else {
/* Globox board: Both EEPROM and TEMP are active-high */
switch (dev) {
case 1: /* EEPROM */
write_mmcr_word(SC520_PIOSET15_0, 0x0100);
break;
case 2: /* Temp Probe */
write_mmcr_word(SC520_PIOSET15_0, 0x0080);
break;
case 0:
write_mmcr_word(SC520_PIOCLR15_0, 0x0180);
break;
default:
printf("Illegal SSI device requested: %d\n", dev);
}
}
}
void spi_init_f(void)
{
read_mmcr_byte(SC520_SYSINFO) ?
spi_eeprom_probe(1) :
mw_eeprom_probe(1);
}
ssize_t spi_read(uchar *addr, int alen, uchar *buffer, int len)
{
int offset;
int i;
offset = 0;
for (i=0;i<alen;i++) {
offset <<= 8;
offset |= addr[i];
}
return read_mmcr_byte(SC520_SYSINFO) ?
spi_eeprom_read(1, offset, buffer, len) :
mw_eeprom_read(1, offset, buffer, len);
}
ssize_t spi_write(uchar *addr, int alen, uchar *buffer, int len)
{
int offset;
int i;
offset = 0;
for (i=0;i<alen;i++) {
offset <<= 8;
offset |= addr[i];
}
return read_mmcr_byte(SC520_SYSINFO) ?
spi_eeprom_write(1, offset, buffer, len) :
mw_eeprom_write(1, offset, buffer, len);
}