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fpga_io.cpp
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fpga_io.cpp
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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <ctype.h>
#include <termios.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include "fpga_io.h"
#include "file_io.h"
#include "input.h"
#include "osd.h"
#include "menu.h"
#include "fpga_base_addr_ac5.h"
#include "fpga_manager.h"
#include "fpga_system_manager.h"
#include "fpga_reset_manager.h"
#include "fpga_nic301.h"
#define FPGA_REG_BASE 0xFF000000
#define FPGA_REG_SIZE 0x01000000
#define MAP_ADDR(x) (volatile uint32_t*)(&map_base[(((uint32_t)(x)) & 0xFFFFFF)>>2])
#define IS_REG(x) (((((uint32_t)(x))-1)>=(FPGA_REG_BASE - 1)) && ((((uint32_t)(x))-1)<(FPGA_REG_BASE + FPGA_REG_SIZE - 1)))
#define fatal(x) munmap((void*)map_base, FPGA_REG_SIZE); close(fd); exit(x)
static struct socfpga_reset_manager *reset_regs = (socfpga_reset_manager *)SOCFPGA_RSTMGR_ADDRESS;
static struct socfpga_fpga_manager *fpgamgr_regs = (socfpga_fpga_manager *)SOCFPGA_FPGAMGRREGS_ADDRESS;
static struct socfpga_system_manager *sysmgr_regs = (socfpga_system_manager *)SOCFPGA_SYSMGR_ADDRESS;
static struct nic301_registers *nic301_regs = (nic301_registers *)SOCFPGA_L3REGS_ADDRESS;
static uint32_t *map_base;
static int fd;
#define writel(val, reg) *MAP_ADDR(reg) = val
#define readl(reg) *MAP_ADDR(reg)
#define clrsetbits_le32(addr, clear, set) writel((readl(addr) & ~(clear)) | (set), addr)
#define setbits_le32(addr, set) writel( readl(addr) | (set), addr)
#define clrbits_le32(addr, clear) writel( readl(addr) & ~(clear), addr)
/* Timeout count */
#define FPGA_TIMEOUT_CNT 0x1000000
/* Set CD ratio */
static void fpgamgr_set_cd_ratio(unsigned long ratio)
{
clrsetbits_le32(&fpgamgr_regs->ctrl,
0x3 << FPGAMGRREGS_CTRL_CDRATIO_LSB,
(ratio & 0x3) << FPGAMGRREGS_CTRL_CDRATIO_LSB);
}
static int fpgamgr_dclkcnt_set(unsigned long cnt)
{
unsigned long i;
/* Clear any existing done status */
if (readl(&fpgamgr_regs->dclkstat))
writel(0x1, &fpgamgr_regs->dclkstat);
/* Write the dclkcnt */
writel(cnt, &fpgamgr_regs->dclkcnt);
/* Wait till the dclkcnt done */
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
if (!readl(&fpgamgr_regs->dclkstat))
continue;
writel(0x1, &fpgamgr_regs->dclkstat);
return 0;
}
return -ETIMEDOUT;
}
/* Check whether FPGA Init_Done signal is high */
static int is_fpgamgr_initdone_high(void)
{
unsigned long val;
val = readl(&fpgamgr_regs->gpio_ext_porta);
return val & FPGAMGRREGS_MON_GPIO_EXT_PORTA_ID_MASK;
}
/* Get the FPGA mode */
static int fpgamgr_get_mode(void)
{
unsigned long val;
val = readl(&fpgamgr_regs->stat);
return val & FPGAMGRREGS_STAT_MODE_MASK;
}
/* Check whether FPGA is ready to be accessed */
static int fpgamgr_test_fpga_ready(void)
{
/* Check for init done signal */
if (!is_fpgamgr_initdone_high())
return 0;
/* Check again to avoid false glitches */
if (!is_fpgamgr_initdone_high())
return 0;
if (fpgamgr_get_mode() != FPGAMGRREGS_MODE_USERMODE)
return 0;
return 1;
}
/*
// Poll until FPGA is ready to be accessed or timeout occurred
static int fpgamgr_poll_fpga_ready(void)
{
unsigned long i;
// If FPGA is blank, wait till WD invoke warm reset
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
// check for init done signal
if (!is_fpgamgr_initdone_high())
continue;
// check again to avoid false glitches
if (!is_fpgamgr_initdone_high())
continue;
return 1;
}
return 0;
}
*/
/* Start the FPGA programming by initialize the FPGA Manager */
static int fpgamgr_program_init(void)
{
unsigned long msel, i;
/* Get the MSEL value */
msel = readl(&fpgamgr_regs->stat);
msel &= FPGAMGRREGS_STAT_MSEL_MASK;
msel >>= FPGAMGRREGS_STAT_MSEL_LSB;
/*
* Set the cfg width
* If MSEL[3] = 1, cfg width = 32 bit
*/
if (msel & 0x8) {
setbits_le32(&fpgamgr_regs->ctrl,
FPGAMGRREGS_CTRL_CFGWDTH_MASK);
/* To determine the CD ratio */
/* MSEL[1:0] = 0, CD Ratio = 1 */
if ((msel & 0x3) == 0x0)
fpgamgr_set_cd_ratio(CDRATIO_x1);
/* MSEL[1:0] = 1, CD Ratio = 4 */
else if ((msel & 0x3) == 0x1)
fpgamgr_set_cd_ratio(CDRATIO_x4);
/* MSEL[1:0] = 2, CD Ratio = 8 */
else if ((msel & 0x3) == 0x2)
fpgamgr_set_cd_ratio(CDRATIO_x8);
}
else { /* MSEL[3] = 0 */
clrbits_le32(&fpgamgr_regs->ctrl,
FPGAMGRREGS_CTRL_CFGWDTH_MASK);
/* To determine the CD ratio */
/* MSEL[1:0] = 0, CD Ratio = 1 */
if ((msel & 0x3) == 0x0)
fpgamgr_set_cd_ratio(CDRATIO_x1);
/* MSEL[1:0] = 1, CD Ratio = 2 */
else if ((msel & 0x3) == 0x1)
fpgamgr_set_cd_ratio(CDRATIO_x2);
/* MSEL[1:0] = 2, CD Ratio = 4 */
else if ((msel & 0x3) == 0x2)
fpgamgr_set_cd_ratio(CDRATIO_x4);
}
/* To enable FPGA Manager configuration */
clrbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_NCE_MASK);
/* To enable FPGA Manager drive over configuration line */
setbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_EN_MASK);
/* Put FPGA into reset phase */
setbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_NCONFIGPULL_MASK);
/* (1) wait until FPGA enter reset phase */
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
if (fpgamgr_get_mode() == FPGAMGRREGS_MODE_RESETPHASE)
break;
}
/* If not in reset state, return error */
if (fpgamgr_get_mode() != FPGAMGRREGS_MODE_RESETPHASE) {
puts("FPGA: Could not reset\n");
return -1;
}
/* Release FPGA from reset phase */
clrbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_NCONFIGPULL_MASK);
/* (2) wait until FPGA enter configuration phase */
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
if (fpgamgr_get_mode() == FPGAMGRREGS_MODE_CFGPHASE)
break;
}
/* If not in configuration state, return error */
if (fpgamgr_get_mode() != FPGAMGRREGS_MODE_CFGPHASE) {
puts("FPGA: Could not configure\n");
return -2;
}
/* Clear all interrupts in CB Monitor */
writel(0xFFF, &fpgamgr_regs->gpio_porta_eoi);
/* Enable AXI configuration */
setbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_AXICFGEN_MASK);
return 0;
}
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
/* Write the RBF data to FPGA Manager */
static void fpgamgr_program_write(const void *rbf_data, unsigned long rbf_size)
{
uint32_t src = (uint32_t)rbf_data;
uint32_t dst = (uint32_t)MAP_ADDR(SOCFPGA_FPGAMGRDATA_ADDRESS);
/* Number of loops for 32-byte long copying. */
uint32_t loops32 = rbf_size / 32;
/* Number of loops for 4-byte long copying + trailing bytes */
uint32_t loops4 = DIV_ROUND_UP(rbf_size % 32, 4);
__asm volatile(
"1: ldmia %0!,{r0-r7} \n"
" stmia %1!,{r0-r7} \n"
" sub %1, #32 \n"
" subs %2, #1 \n"
" bne 1b \n"
" cmp %3, #0 \n"
" beq 3f \n"
"2: ldr %2, [%0], #4 \n"
" str %2, [%1] \n"
" subs %3, #1 \n"
" bne 2b \n"
"3: nop \n"
: "+r"(src), "+r"(dst), "+r"(loops32), "+r"(loops4) :
: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "cc");
}
/* Ensure the FPGA entering config done */
static int fpgamgr_program_poll_cd(void)
{
const uint32_t mask = FPGAMGRREGS_MON_GPIO_EXT_PORTA_NS_MASK |
FPGAMGRREGS_MON_GPIO_EXT_PORTA_CD_MASK;
unsigned long reg, i;
/* (3) wait until full config done */
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
reg = readl(&fpgamgr_regs->gpio_ext_porta);
/* Config error */
if (!(reg & mask)) {
printf("FPGA: Configuration error.\n");
return -3;
}
/* Config done without error */
if (reg & mask)
break;
}
/* Timeout happened, return error */
if (i == FPGA_TIMEOUT_CNT) {
printf("FPGA: Timeout waiting for program.\n");
return -4;
}
/* Disable AXI configuration */
clrbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_AXICFGEN_MASK);
return 0;
}
/* Ensure the FPGA entering init phase */
static int fpgamgr_program_poll_initphase(void)
{
unsigned long i;
/* Additional clocks for the CB to enter initialization phase */
if (fpgamgr_dclkcnt_set(0x4))
return -5;
/* (4) wait until FPGA enter init phase or user mode */
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
if (fpgamgr_get_mode() == FPGAMGRREGS_MODE_INITPHASE)
break;
if (fpgamgr_get_mode() == FPGAMGRREGS_MODE_USERMODE)
break;
}
/* If not in configuration state, return error */
if (i == FPGA_TIMEOUT_CNT)
return -6;
return 0;
}
/* Ensure the FPGA entering user mode */
static int fpgamgr_program_poll_usermode(void)
{
unsigned long i;
/* Additional clocks for the CB to exit initialization phase */
if (fpgamgr_dclkcnt_set(0x5000))
return -7;
/* (5) wait until FPGA enter user mode */
for (i = 0; i < FPGA_TIMEOUT_CNT; i++) {
if (fpgamgr_get_mode() == FPGAMGRREGS_MODE_USERMODE)
break;
}
/* If not in configuration state, return error */
if (i == FPGA_TIMEOUT_CNT)
return -8;
/* To release FPGA Manager drive over configuration line */
clrbits_le32(&fpgamgr_regs->ctrl, FPGAMGRREGS_CTRL_EN_MASK);
return 0;
}
/*
* FPGA Manager to program the FPGA. This is the interface used by FPGA driver.
* Return 0 for sucess, non-zero for error.
*/
static int socfpga_load(const void *rbf_data, size_t rbf_size)
{
unsigned long status;
if ((uint32_t)rbf_data & 0x3) {
printf("FPGA: Unaligned data, realign to 32bit boundary.\n");
return -EINVAL;
}
/* Initialize the FPGA Manager */
status = fpgamgr_program_init();
if (status)
return status;
/* Write the RBF data to FPGA Manager */
fpgamgr_program_write(rbf_data, rbf_size);
/* Ensure the FPGA entering config done */
status = fpgamgr_program_poll_cd();
if (status)
return status;
/* Ensure the FPGA entering init phase */
status = fpgamgr_program_poll_initphase();
if (status)
return status;
/* Ensure the FPGA entering user mode */
return fpgamgr_program_poll_usermode();
}
static void do_bridge(uint32_t enable)
{
if (enable)
{
writel(0x00003FFF, (void*)(SOCFPGA_SDR_ADDRESS + 0x5080));
writel(0x00000000, &reset_regs->brg_mod_reset);
writel(0x00000019, &nic301_regs->remap);
}
else
{
writel(0, &sysmgr_regs->fpgaintfgrp_module);
writel(0, (void*)(SOCFPGA_SDR_ADDRESS + 0x5080));
writel(7, &reset_regs->brg_mod_reset);
writel(1, &nic301_regs->remap);
}
}
static int make_env(const char *name, const char *cfg)
{
if ((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1) return -1;
void* buf = mmap(0, 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0x1FFFF000);
if (buf == (void *)-1)
{
printf("Unable to mmap(/dev/mem)\n");
close(fd);
return -1;
}
volatile char* str = (volatile char*)buf;
memset((void*)str, 0, 0xF00);
*str++ = 0x21;
*str++ = 0x43;
*str++ = 0x65;
*str++ = 0x87;
*str++ = 'c';
*str++ = 'o';
*str++ = 'r';
*str++ = 'e';
*str++ = '=';
*str++ = '"';
for (uint32_t i = 0; i < strlen(name); i++)
{
*str++ = name[i];
}
*str++ = '"';
*str++ = '\n';
FileLoad(cfg, (void*)str, 0);
munmap(buf, 0x1000);
return 0;
}
int fpga_load_rbf(const char *name, const char *cfg, const char *xml)
{
OsdDisable();
static char path[1024];
int ret = 0;
if(cfg)
{
fpga_core_reset(1);
make_env(name, cfg);
do_bridge(0);
reboot(0);
}
printf("Loading RBF: %s\n", name);
if(name[0] == '/') strcpy(path, name);
else sprintf(path, "%s/%s", !strcasecmp(name, "menu.rbf") ? getStorageDir(0) : getRootDir(), name);
int rbf = open(path, O_RDONLY);
if (rbf < 0)
{
char error[4096];
snprintf(error,4096,"%s\nNot Found", name);
printf("Couldn't open file %s\n", path);
Info(error,5000);
return -1;
}
else
{
struct stat64 st;
if (fstat64(rbf, &st)<0)
{
printf("Couldn't get info of file %s\n", path);
ret = -1;
}
else
{
printf("Bitstream size: %lld bytes\n", st.st_size);
void *buf = malloc(st.st_size);
if (!buf)
{
printf("Couldn't allocate %llu bytes.\n", st.st_size);
ret = -1;
}
else
{
fpga_core_reset(1);
if (read(rbf, buf, st.st_size)<st.st_size)
{
printf("Couldn't read file %s\n", name);
ret = -1;
}
else
{
void *p = buf;
__off64_t sz = st.st_size;
if (!memcmp(buf, "MiSTer", 6))
{
sz = *(uint32_t*)(((uint8_t*)buf) + 12);
p = (void*)(((uint8_t*)buf) + 16);
}
do_bridge(0);
ret = socfpga_load(p, sz);
if (ret)
{
printf("Error %d while loading %s\n", ret, path);
}
else
{
do_bridge(1);
}
}
free(buf);
}
}
}
close(rbf);
app_restart(!strcasecmp(name, "menu.rbf") ? "menu.rbf" : path, xml);
return ret;
}
static uint32_t gpo_copy = 0;
void inline fpga_gpo_write(uint32_t value)
{
gpo_copy = value;
writel(value, (void*)(SOCFPGA_MGR_ADDRESS + 0x10));
}
#define fpga_gpo_read() gpo_copy //readl((void*)(SOCFPGA_MGR_ADDRESS + 0x10))
#define fpga_gpi_read() (int)readl((void*)(SOCFPGA_MGR_ADDRESS + 0x14))
void fpga_core_write(uint32_t offset, uint32_t value)
{
if (offset <= 0x1FFFFF) writel(value, (void*)(SOCFPGA_LWFPGASLAVES_ADDRESS + (offset & ~3)));
}
uint32_t fpga_core_read(uint32_t offset)
{
if (offset <= 0x1FFFFF) return readl((void*)(SOCFPGA_LWFPGASLAVES_ADDRESS + (offset & ~3)));
return 0;
}
int fpga_io_init()
{
if ((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1) return -1;
map_base = (uint32_t*)mmap(0, FPGA_REG_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, FPGA_REG_BASE);
if (map_base == (void *)-1)
{
printf("Unable to mmap(/dev/mem)\n");
close(fd);
return -1;
}
fpga_gpo_write(0);
return 0;
}
int fpga_core_id()
{
uint32_t gpo = (fpga_gpo_read() & 0x7FFFFFFF);
fpga_gpo_write(gpo);
uint32_t coretype = fpga_gpi_read();
gpo |= 0x80000000;
fpga_gpo_write(gpo);
if ((coretype >> 8) != 0x5CA623) return -1;
return coretype & 0xFF;
}
int fpga_get_fio_size()
{
return (fpga_gpi_read() >> 16) & 1;
}
int fpga_get_io_version()
{
return (fpga_gpi_read() >> 18) & 3;
}
void fpga_set_led(uint32_t on)
{
uint32_t gpo = fpga_gpo_read();
fpga_gpo_write(on ? gpo | 0x20000000 : gpo & ~0x20000000);
}
int fpga_get_buttons()
{
fpga_gpo_write(fpga_gpo_read() | 0x80000000);
int gpi = fpga_gpi_read();
if (gpi < 0) gpi = 0; // FPGA is not in user mode. Ignore the data;
return (gpi >> 29) & 3;
}
int fpga_get_io_type()
{
fpga_gpo_write(fpga_gpo_read() | 0x80000000);
return (fpga_gpi_read() >> 28) & 1;
}
void reboot(int cold)
{
sync();
fpga_core_reset(1);
usleep(500000);
writel(cold ? 0 : 0x1, &reset_regs->tstscratch);
writel(2, &reset_regs->ctrl);
while (1);
}
char *getappname()
{
static char dest[PATH_MAX];
memset(dest, 0, sizeof(dest));
char path[64];
sprintf(path, "/proc/%d/exe", getpid());
readlink(path, dest, PATH_MAX);
return dest;
}
void app_restart(const char *path, const char *xml)
{
sync();
fpga_core_reset(1);
input_switch(0);
input_uinp_destroy();
char *appname = getappname();
printf("restarting the %s\n", appname);
execl(appname, appname, path, xml, NULL);
printf("Something went wrong. Rebooting...\n");
reboot(0);
}
void fpga_core_reset(int reset)
{
uint32_t gpo = fpga_gpo_read() & ~0xC0000000;
fpga_gpo_write(reset ? gpo | 0x40000000 : gpo | 0x80000000);
}
int is_fpga_ready(int quick)
{
if (quick)
{
return (fpga_gpi_read() >= 0);
}
return fpgamgr_test_fpga_ready();
}
#define SSPI_STROBE (1<<17)
#define SSPI_ACK SSPI_STROBE
void fpga_spi_en(uint32_t mask, uint32_t en)
{
uint32_t gpo = fpga_gpo_read() | 0x80000000;
fpga_gpo_write(en ? gpo | mask : gpo & ~mask);
}
uint16_t fpga_spi(uint16_t word)
{
uint32_t gpo = (fpga_gpo_read() & ~(0xFFFF | SSPI_STROBE)) | word;
fpga_gpo_write(gpo);
fpga_gpo_write(gpo | SSPI_STROBE);
int gpi;
do
{
gpi = fpga_gpi_read();
if (gpi < 0)
{
printf("GPI[31]==1. FPGA is uninitialized?\n");
return 0;
}
} while (!(gpi & SSPI_ACK));
fpga_gpo_write(gpo);
do
{
gpi = fpga_gpi_read();
if (gpi < 0)
{
printf("GPI[31]==1. FPGA is uninitialized?\n");
return 0;
}
} while (gpi & SSPI_ACK);
return (uint16_t)gpi;
}
uint16_t fpga_spi_fast(uint16_t word)
{
uint32_t gpo = (fpga_gpo_read() & ~(0xFFFF | SSPI_STROBE)) | word;
fpga_gpo_write(gpo);
fpga_gpo_write(gpo | SSPI_STROBE);
fpga_gpo_write(gpo);
return (uint16_t)fpga_gpi_read();
}