On Fri, Aug 26, 2022 at 01:57:21PM +0300, Ivan Bornyakov wrote:
> On Thu, Aug 25, 2022 at 02:24:32PM +0300, Ivan Bornyakov wrote:
> > Add support to the FPGA manager for programming Lattice ECP5 and MachXO2
> > FPGAs over slave SPI sysCONFIG interface.
> >
> > Signed-off-by: Ivan Bornyakov <i.bornyakov@xxxxxxxxxxx>
> > ---
> >
> > ... snip ...
> >
> > +
> > +struct sysconfig_priv {
> > + struct gpio_desc *program;
> > + struct gpio_desc *init;
> > + struct gpio_desc *done;
> > + struct spi_device *spi;
> > + u8 isc_enable_operand;
> > + u8 isc_erase_operand;
> > +};
>
> As Johannes Zink working on adding I2C to MachXO2, I am thinking how
> about we add to struct sysconfig_priv a callback
>
> int (*sysconfig_transfer)(struct sysconfig_priv,
> const void *tx_buf, size_t tx_len,
> void *rx_buf, size_t rx_len)
>
> For SPI it would be defined like this:
>
> static int sysconfig_spi_transfer(struct sysconfig_priv *data,
> const void *tx_buf, size_t tx_len,
> void *rx_buf, size_t rx_len)
> {
> if (!rx_buf)
> return spi_write(data->spi, tx_buf, tx_size);
>
> return spi_write_then_read(data->spi, tx_buf, tx_size, rx_buf, rx_size);
> }
>
> And later in sysconfig_ commands we would call this callback.
>
> Would it be a good enough starting base for Johannes to add I2C interface
> for MachXO2?
>
> >
> > ... snip ...
> >
> > +static int sysconfig_isc_enable(struct sysconfig_priv *data)
> > +{
> > + u8 isc_enable[] = SYSCONFIG_ISC_ENABLE;
> > + u32 status;
> > + int ret;
> > +
> > + isc_enable[1] = data->isc_enable_operand;
> > +
> > + ret = spi_write(data->spi, isc_enable, sizeof(isc_enable));
> > + if (ret)
> > + return ret;
> > +
> > + ret = sysconfig_poll_status(data, &status);
> > + if (ret || (status & SYSCONFIG_STATUS_FAIL))
> > + return ret ? : -EFAULT;
> > +
> > + return 0;
> > +}
>
> Quirks for I2C enable and refresh commands are 3-bytes instead of
> 4-bytes for SPI can be added here. Just check which of data->spi or
> data->i2c is not NULL.
>
Actually, here is a patch for your tinkering.
I guess, what you need to do for MachXO2 I2C support is:
1) implement sysconfig_transfer callback for I2C. Something like this:
static int sysconfig_i2c_transfer(struct sysconfig_priv *data,
const void *tx_buf, size_t tx_len,
void *rx_buf, size_t rx_len)
{
struct i2c_client *i2c = data->i2c;
struct i2c_msg msg[] = {
{
.addr = i2c->addr,
.flags = 0,
.buf = tx_buf,
.len = tx_len,
}, {
.addr = i2c->addr,
.flags = I2C_M_RD,
.buf = rx_buf,
.len = rx_len,
}
};
if (!rx_buf)
return i2c_master_send(i2c, tx_buf, tx_len);
return i2c_transfer(i2c->adapter, msg, ARRAY_SIZE(msg));
}
2) add quirks for 3-byte transfer to sysconfig_refresh() and
sysconfig_isc_enable()
3) add probe routine
4) add separate fpga_manager_ops->write() for I2C
state(), write_init() and write_complete() can be reused
---
drivers/fpga/lattice-sysconfig-spi.c | 46 ++++++++++++++++++++--------
1 file changed, 33 insertions(+), 13 deletions(-)
diff --git a/drivers/fpga/lattice-sysconfig-spi.c b/drivers/fpga/lattice-sysconfig-spi.c
index 145b5b27b88d..c2caf613d2f0 100644
--- a/drivers/fpga/lattice-sysconfig-spi.c
+++ b/drivers/fpga/lattice-sysconfig-spi.c
@@ -41,8 +41,21 @@ struct sysconfig_priv {
struct spi_device *spi;
u8 isc_enable_operand;
u8 isc_erase_operand;
+ int (*sysconfig_transfer)(struct sysconfig_priv *data,
+ const void *tx_buf, size_t tx_len,
+ void *rx_buf, size_t rx_len);
};
+static int sysconfig_spi_transfer(struct sysconfig_priv *data,
+ const void *tx_buf, size_t tx_len,
+ void *rx_buf, size_t rx_len)
+{
+ if (!rx_buf)
+ return spi_write(data->spi, tx_buf, tx_len);
+
+ return spi_write_then_read(data->spi, tx_buf, tx_len, rx_buf, rx_len);
+}
+
static int sysconfig_poll_busy(struct sysconfig_priv *data)
{
const u8 lsc_check_busy[] = SYSCONFIG_LSC_CHECK_BUSY;
@@ -50,9 +63,9 @@ static int sysconfig_poll_busy(struct sysconfig_priv *data)
u8 busy;
while (retries--) {
- ret = spi_write_then_read(data->spi,
- lsc_check_busy, sizeof(lsc_check_busy),
- &busy, sizeof(busy));
+ ret = data->sysconfig_transfer(data, lsc_check_busy,
+ sizeof(lsc_check_busy),
+ &busy, sizeof(busy));
if (ret)
return ret;
@@ -71,9 +84,9 @@ static int sysconfig_read_status(struct sysconfig_priv *data, u32 *status)
__be32 device_status;
int ret;
- ret = spi_write_then_read(data->spi,
- lsc_read_status, sizeof(lsc_read_status),
- &device_status, sizeof(device_status));
+ ret = data->sysconfig_transfer(data, lsc_read_status,
+ sizeof(lsc_read_status),
+ &device_status, sizeof(device_status));
if (ret)
return ret;
@@ -116,7 +129,8 @@ static int sysconfig_refresh(struct sysconfig_priv *data)
static const u8 lsc_refresh[] = SYSCONFIG_LSC_REFRESH;
int ret;
- ret = spi_write(data->spi, lsc_refresh, sizeof(lsc_refresh));
+ ret = data->sysconfig_transfer(data, lsc_refresh, sizeof(lsc_refresh),
+ NULL, 0);
if (ret)
return ret;
@@ -133,7 +147,8 @@ static int sysconfig_isc_enable(struct sysconfig_priv *data)
isc_enable[1] = data->isc_enable_operand;
- ret = spi_write(data->spi, isc_enable, sizeof(isc_enable));
+ ret = data->sysconfig_transfer(data, isc_enable, sizeof(isc_enable),
+ NULL, 0);
if (ret)
return ret;
@@ -152,7 +167,8 @@ static int sysconfig_isc_erase(struct sysconfig_priv *data)
isc_erase[1] = data->isc_erase_operand;
- ret = spi_write(data->spi, isc_erase, sizeof(isc_erase));
+ ret = data->sysconfig_transfer(data, isc_erase, sizeof(isc_erase),
+ NULL, 0);
if (ret)
return ret;
@@ -178,7 +194,8 @@ static int sysconfig_lsc_init_addr(struct sysconfig_priv *data)
{
const u8 lsc_init_addr[] = SYSCONFIG_LSC_INIT_ADDR;
- return spi_write(data->spi, lsc_init_addr, sizeof(lsc_init_addr));
+ return data->sysconfig_transfer(data, lsc_init_addr,
+ sizeof(lsc_init_addr), NULL, 0);
}
static int sysconfig_lsc_bitstream_burst(struct sysconfig_priv *data)
@@ -202,7 +219,8 @@ static int sysconfig_isc_prog_done(struct sysconfig_priv *data)
u32 status;
int ret;
- ret = spi_write(data->spi, isc_prog_done, sizeof(isc_prog_done));
+ ret = data->sysconfig_transfer(data, isc_prog_done,
+ sizeof(isc_prog_done), NULL, 0);
if (ret)
return ret;
@@ -220,7 +238,8 @@ static int sysconfig_isc_disable(struct sysconfig_priv *data)
{
const u8 isc_disable[] = SYSCONFIG_ISC_DISABLE;
- return spi_write(data->spi, isc_disable, sizeof(isc_disable));
+ return data->sysconfig_transfer(data, isc_disable, sizeof(isc_disable),
+ NULL, 0);
}
static enum fpga_mgr_states ecp5_ops_state(struct fpga_manager *mgr)
@@ -336,7 +355,7 @@ static int ecp5_ops_write_complete(struct fpga_manager *mgr,
spi_bus_unlock(spi->controller);
/* Toggle CS and wait for bitstream write to finish */
- ret = spi_write(spi, NULL, 0);
+ ret = priv->sysconfig_transfer(priv, NULL, 0, NULL, 0);
if (!ret)
ret = sysconfig_poll_busy(priv);
@@ -575,6 +594,7 @@ static int sysconfig_probe(struct spi_device *spi)
return -ENOMEM;
priv->spi = spi;
+ priv->sysconfig_transfer = sysconfig_spi_transfer;
probe_func = of_device_get_match_data(&spi->dev);
if (!probe_func) {
--
2.37.2
