inline void serialConfigWriteByte(unsigned char val){
unsigned char bitCount = 0 ;
unsigned char valBuf = val ;
for(bitCount = 0 ; bitCount < 8 ; bitCount ++){
ssiClearClk();
if((valBuf & 0x80) != 0){
ssiSetData();
}else{
ssiClearData();
}
//__delay_cycles(SSI_DELAY);
ssiSetClk();
valBuf = (valBuf << 1);
//__delay_cycles(SSI_DELAY);
}
}
int loadBitFile(struct i2c_client * io_cli, const unsigned char * bitBuffer_user, const unsigned int length)
{
int iCfg;
unsigned long int i;
unsigned long int timer = 0;
unsigned char * bitBuffer;
unsigned char i2c_buffer[4];
//request_mem_region(GPIO3_BASE + 0x190, 8, gDrvrName);
gpio_regs = ioremap_nocache(GPIO3_BASE + 0x190, 2 * sizeof(int));
bitBuffer = kmalloc(length, GFP_KERNEL);
if (bitBuffer == NULL || copy_from_user(bitBuffer, bitBuffer_user, length)) {
printk("Failed allocate buffer for configuration file \n");
return -ENOTTY;
}
iCfg = gpio_request(SSI_CLK, "ssi_clk");
if (iCfg < 0) {
printk("Failed to take control over ssi_clk pin \n");
return -ENOTTY;
}
iCfg = gpio_request(SSI_DATA, "ssi_data");
if (iCfg < 0) {
printk("Failed to take control over ssi_data pin \n");
return -ENOTTY;
}
i2c_buffer[0] = I2C_IO_EXP_CONFIG_REG;
i2c_buffer[1] = 0xFF;
i2c_buffer[1] &= ~((1 << SSI_PROG) | (1 << MODE1) | (1 << MODE0));
i2c_master_send(io_cli, i2c_buffer, 2); // set SSI_PROG, MODE0, MODE1 as output others as inputs
i2c_set_pin(io_cli, MODE0, 1);
i2c_set_pin(io_cli, MODE1, 1);
i2c_set_pin(io_cli, SSI_PROG, 0);
gpio_direction_output(SSI_CLK, 0);
gpio_direction_output(SSI_DATA, 0);
gpio_set_value(SSI_CLK, 0);
i2c_set_pin(io_cli, SSI_PROG, 1);
__delay_cycles(10 * SSI_DELAY);
i2c_set_pin(io_cli, SSI_PROG, 0);
__delay_cycles(5 * SSI_DELAY);
while (i2c_get_pin(io_cli, SSI_INIT) > 0 && timer < 200)
timer++; // waiting for init pin to go down
if (timer >= 200) {
printk("FPGA did not answer to prog request, init pin not going low \n");
i2c_set_pin(io_cli, SSI_PROG, 1);
gpio_free(SSI_CLK);
gpio_free(SSI_DATA);
return -ENOTTY;
}
timer = 0;
__delay_cycles(5 * SSI_DELAY);
i2c_set_pin(io_cli, SSI_PROG, 1);
while (i2c_get_pin(io_cli, SSI_INIT) == 0 && timer < 256) { // need to find a better way ...
timer++; // waiting for init pin to go up
}
if (timer >= 256) {
printk("FPGA did not answer to prog request, init pin not going high \n");
gpio_free(SSI_CLK);
gpio_free(SSI_DATA);
return -ENOTTY;
}
timer = 0;
printk("Starting configuration of %d bits \n", length * 8);
for (i = 0; i < length; i++) {
serialConfigWriteByte(bitBuffer[i]);
schedule();
}
printk("Waiting for done pin to go high \n");
while (timer < 50) {
ssiClearClk();
__delay_cycles(SSI_DELAY);
ssiSetClk();
__delay_cycles(SSI_DELAY);
timer++;
}
gpio_set_value(SSI_CLK, 0);
gpio_set_value(SSI_DATA, 1);
if (i2c_get_pin(io_cli, SSI_DONE) == 0) {
printk("FPGA prog failed, done pin not going high \n");
gpio_free(SSI_CLK);
gpio_free(SSI_DATA);
return -ENOTTY;
}
i2c_buffer[0] = I2C_IO_EXP_CONFIG_REG;
i2c_buffer[1] = 0xDC;
i2c_master_send(io_cli, i2c_buffer, 2); // set all unused config pins as input (keeping mode pins and PROG as output)
gpio_direction_input(SSI_CLK);
gpio_direction_input(SSI_DATA);
gpio_free(SSI_CLK);
gpio_free(SSI_DATA);
iounmap(gpio_regs);
//release_mem_region(GPIO3_BASE + 0x190, 8);
kfree(bitBuffer);
return length;
}