diff mbox

[2/2] fpga: lattice machxo2: Add Lattice MachXO2 support

Message ID 1521653726-24625-3-git-send-email-p.pisati@gmail.com (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Paolo Pisati March 21, 2018, 5:35 p.m. UTC
This patch adds support to the FPGA manager for programming
MachXO2 device’s internal flash memory, via slave SPI.

Signed-off-by: Paolo Pisati <p.pisati@gmail.com>
---
 drivers/fpga/Kconfig       |   8 +
 drivers/fpga/Makefile      |   1 +
 drivers/fpga/machxo2-spi.c | 405 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 414 insertions(+)
 create mode 100644 drivers/fpga/machxo2-spi.c

Comments

Joe Perches March 21, 2018, 6:04 p.m. UTC | #1
On Wed, 2018-03-21 at 18:35 +0100, Paolo Pisati wrote:
> This patch adds support to the FPGA manager for programming
> MachXO2 device’s internal flash memory, via slave SPI.

style trivia:

> diff --git a/drivers/fpga/machxo2-spi.c b/drivers/fpga/machxo2-spi.c
[]
> +static int get_status(struct spi_device *spi, unsigned long *status)
> +{
> +	struct spi_message msg;
> +	struct spi_transfer rx, tx;
> +	u8 cmd[] = LSC_READ_STATUS;

static const u8 cmd[]
here and everywhere else as all the tx_buf assignments 
of cmd are to const void *

> +	int ret;
> +
> +	memset(&rx, 0, sizeof(rx));
> +	memset(&tx, 0, sizeof(tx));
> +	tx.tx_buf = cmd;

[]

> +#ifdef DEBUG
> +static void dump_status_reg(unsigned long *status)
> +{

Instead of multiple declarations of dump_status_reg
it's frequently nicer to use a style like

static void debug_func(args...)
{
#ifdef DEBUG
	[code...]
#endif
}

so if function arguments ever need to be changed
it's only required to be changed in one spot and
not multiply compilation tested with and without
the DEBUG definition

> +	char *ferr;
> +
> +	switch (get_err(status)) {
> +	case ENOERR:
> +		ferr = "No Error";
> +		break;
> +	case EID:
> +		ferr = "ID ERR";
> +		break;
> +	case ECMD:
> +		ferr = "CMD ERR";
> +		break;
> +	case ECRC:
> +		ferr = "CRC ERR";
> +		break;
> +	case EPREAM:
> +		ferr = "Preamble ERR";
> +		break;
> +	case EABRT:
> +		ferr = "Abort ERR";
> +		break;
> +	case EOVERFL:
> +		ferr = "Overflow ERR";
> +		break;
> +	case ESDMEOF:
> +		ferr = "SDM EOF";
> +		break;
> +	default:
> +		ferr = "Default switch case";
> +	}

It's frequently nicer to use a static function
for these enum -> string conversions like:

static const char *get_err_string(unsigned long err)
{
	switch (err) {
	case ENOERR:	return "No Error";
	case EID:	return "ID ERR";
	case ECMD:	return "CMD ERR";
	[...]
	}
	return "default switch case";
}

> +	pr_debug("machxo2 status: 0x%08lX - done=%d, cfgena=%d, busy=%d, fail=%d, devver=%d, err=%s\n",
> +	       *status, test_bit(DONE, status), test_bit(ENAB, status),
> +	       test_bit(BUSY, status), test_bit(FAIL, status),
> +		   test_bit(DVER, status), ferr);

So instead of ferr, this could use
	get_err_string(*status)

And please try to keep a consistent alignment for
indentation of multiple line statements

> +}
> +#else
> +static void dump_status_reg(unsigned long *status) {}
> +#endif
> +
> +static int wait_until_not_busy(struct spi_device *spi)
> +{
> +	unsigned long status;
> +	int ret, loop = 0;
> +
> +	do {
> +		ret = get_status(spi, &status);
> +		if (ret)
> +			break;
> +		if (++loop >= MACHXO2_MAX_BUSY_LOOP) {
> +			ret = -EBUSY;
> +			break;
> +		}
> +	} while (test_bit(BUSY, &status));
> +
> +	return ret;
> +}

Direct returns are OK and would shorten the function
line count.

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Paolo Pisati March 22, 2018, 5:26 p.m. UTC | #2
On Wed, Mar 21, 2018 at 11:04:52AM -0700, Joe Perches wrote:
> 
> static const u8 cmd[]
> here and everywhere else as all the tx_buf assignments 
> of cmd are to const void *

Ok
 
> Instead of multiple declarations of dump_status_reg
> it's frequently nicer to use a style like
> 
> static void debug_func(args...)
> {
> #ifdef DEBUG
> 	[code...]
> #endif
> }
> 
> so if function arguments ever need to be changed
> it's only required to be changed in one spot and
> not multiply compilation tested with and without
> the DEBUG definition

Ok
 
> It's frequently nicer to use a static function
> for these enum -> string conversions like:
> 
> static const char *get_err_string(unsigned long err)
> {
> 	switch (err) {
> 	case ENOERR:	return "No Error";
> 	case EID:	return "ID ERR";
> 	case ECMD:	return "CMD ERR";
> 	[...]
> 	}
> 	return "default switch case";
> }

Ok - checkpatch complained when i put the "case ...: return ...;" on the same
line as you did here, that is why i ended up with the ugly "case...: $string;
break" all on different lines
 
> > +	pr_debug("machxo2 status: 0x%08lX - done=%d, cfgena=%d, busy=%d, fail=%d, devver=%d, err=%s\n",
> > +	       *status, test_bit(DONE, status), test_bit(ENAB, status),
> > +	       test_bit(BUSY, status), test_bit(FAIL, status),
> > +		   test_bit(DVER, status), ferr);
> 
> So instead of ferr, this could use
> 	get_err_string(*status)
> 
> And please try to keep a consistent alignment for
> indentation of multiple line statements

I tried, but then checkpatch complained again about the indentation of the above block
and i literally had to guess...

Anyhow, thanks, i'll send a v8 with all these style fixes.
Joe Perches March 22, 2018, 6:30 p.m. UTC | #3
On Thu, 2018-03-22 at 18:26 +0100, Paolo Pisati wrote:
> > It's frequently nicer to use a static function
> > for these enum -> string conversions like:
> > 
> > static const char *get_err_string(unsigned long err)
> > {
> > 	switch (err) {
> > 	case ENOERR:	return "No Error";
> > 	case EID:	return "ID ERR";
> > 	case ECMD:	return "CMD ERR";
> > 	[...]
> > 	}
> > 	return "default switch case";
> > }
> 
> Ok - checkpatch complained when i put the "case ...: return ...;" on the same
> line as you did here, that is why i ended up with the ugly "case...: $string;
> break" all on different lines

checkpatch is brainless and stupid and if it
recommends stupid consistency over readability,
ignore it.
 
> > > +	pr_debug("machxo2 status: 0x%08lX - done=%d, cfgena=%d, busy=%d, fail=%d, devver=%d, err=%s\n",
> > > +	       *status, test_bit(DONE, status), test_bit(ENAB, status),
> > > +	       test_bit(BUSY, status), test_bit(FAIL, status),
> > > +		   test_bit(DVER, status), ferr);
> > 
> > So instead of ferr, this could use
> > 	get_err_string(*status)
> > 
> > And please try to keep a consistent alignment for
> > indentation of multiple line statements
> 
> I tried, but then checkpatch complained again about the indentation of the above block
> and i literally had to guess...

I think it only complained about the
2nd line that starts *status because it
doesn't align with the open parenthesis
of pr_debug

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Alan Tull March 22, 2018, 9:32 p.m. UTC | #4
On Wed, Mar 21, 2018 at 1:04 PM, Joe Perches <joe@perches.com> wrote:
> On Wed, 2018-03-21 at 18:35 +0100, Paolo Pisati wrote:
>> This patch adds support to the FPGA manager for programming
>> MachXO2 device’s internal flash memory, via slave SPI.
>
> style trivia:
>
>> diff --git a/drivers/fpga/machxo2-spi.c b/drivers/fpga/machxo2-spi.c
> []
>> +static int get_status(struct spi_device *spi, unsigned long *status)
>> +{
>> +     struct spi_message msg;
>> +     struct spi_transfer rx, tx;
>> +     u8 cmd[] = LSC_READ_STATUS;
>
> static const u8 cmd[]
> here and everywhere else as all the tx_buf assignments
> of cmd are to const void *

Why *static* const u8 cmd[]?

Alan

>
>> +     int ret;
>> +
>> +     memset(&rx, 0, sizeof(rx));
>> +     memset(&tx, 0, sizeof(tx));
>> +     tx.tx_buf = cmd;
>
> []
>
>> +#ifdef DEBUG
>> +static void dump_status_reg(unsigned long *status)
>> +{
>
> Instead of multiple declarations of dump_status_reg
> it's frequently nicer to use a style like
>
> static void debug_func(args...)
> {
> #ifdef DEBUG
>         [code...]
> #endif
> }
>
> so if function arguments ever need to be changed
> it's only required to be changed in one spot and
> not multiply compilation tested with and without
> the DEBUG definition
>
>> +     char *ferr;
>> +
>> +     switch (get_err(status)) {
>> +     case ENOERR:
>> +             ferr = "No Error";
>> +             break;
>> +     case EID:
>> +             ferr = "ID ERR";
>> +             break;
>> +     case ECMD:
>> +             ferr = "CMD ERR";
>> +             break;
>> +     case ECRC:
>> +             ferr = "CRC ERR";
>> +             break;
>> +     case EPREAM:
>> +             ferr = "Preamble ERR";
>> +             break;
>> +     case EABRT:
>> +             ferr = "Abort ERR";
>> +             break;
>> +     case EOVERFL:
>> +             ferr = "Overflow ERR";
>> +             break;
>> +     case ESDMEOF:
>> +             ferr = "SDM EOF";
>> +             break;
>> +     default:
>> +             ferr = "Default switch case";
>> +     }
>
> It's frequently nicer to use a static function
> for these enum -> string conversions like:
>
> static const char *get_err_string(unsigned long err)
> {
>         switch (err) {
>         case ENOERR:    return "No Error";
>         case EID:       return "ID ERR";
>         case ECMD:      return "CMD ERR";
>         [...]
>         }
>         return "default switch case";
> }
>
>> +     pr_debug("machxo2 status: 0x%08lX - done=%d, cfgena=%d, busy=%d, fail=%d, devver=%d, err=%s\n",
>> +            *status, test_bit(DONE, status), test_bit(ENAB, status),
>> +            test_bit(BUSY, status), test_bit(FAIL, status),
>> +                test_bit(DVER, status), ferr);
>
> So instead of ferr, this could use
>         get_err_string(*status)
>
> And please try to keep a consistent alignment for
> indentation of multiple line statements
>
>> +}
>> +#else
>> +static void dump_status_reg(unsigned long *status) {}
>> +#endif
>> +
>> +static int wait_until_not_busy(struct spi_device *spi)
>> +{
>> +     unsigned long status;
>> +     int ret, loop = 0;
>> +
>> +     do {
>> +             ret = get_status(spi, &status);
>> +             if (ret)
>> +                     break;
>> +             if (++loop >= MACHXO2_MAX_BUSY_LOOP) {
>> +                     ret = -EBUSY;
>> +                     break;
>> +             }
>> +     } while (test_bit(BUSY, &status));
>> +
>> +     return ret;
>> +}
>
> Direct returns are OK and would shorten the function
> line count.
>
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Joe Perches March 22, 2018, 9:34 p.m. UTC | #5
On Thu, 2018-03-22 at 16:32 -0500, Alan Tull wrote:
> On Wed, Mar 21, 2018 at 1:04 PM, Joe Perches <joe@perches.com> wrote:
> > On Wed, 2018-03-21 at 18:35 +0100, Paolo Pisati wrote:
> > > This patch adds support to the FPGA manager for programming
> > > MachXO2 device’s internal flash memory, via slave SPI.
> > 
> > style trivia:
> > 
> > > diff --git a/drivers/fpga/machxo2-spi.c b/drivers/fpga/machxo2-spi.c
> > 
> > []
> > > +static int get_status(struct spi_device *spi, unsigned long *status)
> > > +{
> > > +     struct spi_message msg;
> > > +     struct spi_transfer rx, tx;
> > > +     u8 cmd[] = LSC_READ_STATUS;
> > 
> > static const u8 cmd[]
> > here and everywhere else as all the tx_buf assignments
> > of cmd are to const void *
> 
> Why *static* const u8 cmd[]?

So various compilers don't reload it on each call.

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diff mbox

Patch

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index ad5448f..65ccbc5 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -38,6 +38,14 @@  config FPGA_MGR_ALTERA_PS_SPI
 	  FPGA manager driver support for Altera Arria/Cyclone/Stratix
 	  using the passive serial interface over SPI.
 
+config FPGA_MGR_MACHXO2_SPI
+	tristate "Lattice MachXO2 SPI"
+	depends on SPI
+	help
+	  FPGA manager driver support for Lattice MachXO2 configuration
+	  over slave SPI interface.
+
+
 config FPGA_MGR_SOCFPGA
 	tristate "Altera SOCFPGA FPGA Manager"
 	depends on ARCH_SOCFPGA || COMPILE_TEST
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index f98dcf1..38abb08 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -10,6 +10,7 @@  obj-$(CONFIG_FPGA)			+= fpga-mgr.o
 obj-$(CONFIG_FPGA_MGR_ALTERA_CVP)	+= altera-cvp.o
 obj-$(CONFIG_FPGA_MGR_ALTERA_PS_SPI)	+= altera-ps-spi.o
 obj-$(CONFIG_FPGA_MGR_ICE40_SPI)	+= ice40-spi.o
+obj-$(CONFIG_FPGA_MGR_MACHXO2_SPI)	+= machxo2-spi.o
 obj-$(CONFIG_FPGA_MGR_SOCFPGA)		+= socfpga.o
 obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10)	+= socfpga-a10.o
 obj-$(CONFIG_FPGA_MGR_TS73XX)		+= ts73xx-fpga.o
diff --git a/drivers/fpga/machxo2-spi.c b/drivers/fpga/machxo2-spi.c
new file mode 100644
index 0000000..9508608
--- /dev/null
+++ b/drivers/fpga/machxo2-spi.c
@@ -0,0 +1,405 @@ 
+// SPDX-License-Identifier: GPL-2.0
+// Lattice MachXO2 Slave SPI Driver
+//
+// Manage Lattice FPGA firmware that is loaded over SPI using
+// the slave serial configuration interface.
+//
+// Copyright (C) 2018 Paolo Pisati <p.pisati@gmail.com>
+
+//#define DEBUG
+
+#include <linux/delay.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/spi/spi.h>
+
+/* MachXO2 Programming Guide - sysCONFIG Programming Commands */
+#define IDCODE_PUB			{0xe0, 0x00, 0x00, 0x00}
+#define ISC_ENABLE			{0xc6, 0x08, 0x00, 0x00}
+#define ISC_ERASE			{0x0e, 0x04, 0x00, 0x00}
+#define ISC_PROGRAMDONE		{0x5e, 0x00, 0x00, 0x00}
+#define LSC_INITADDRESS		{0x46, 0x00, 0x00, 0x00}
+#define LSC_PROGINCRNV		{0x70, 0x00, 0x00, 0x01}
+#define LSC_READ_STATUS		{0x3c, 0x00, 0x00, 0x00}
+#define LSC_REFRESH			{0x79, 0x00, 0x00, 0x00}
+
+/*
+ * Max CCLK in Slave SPI mode according to 'MachXO2 Family Data
+ * Sheet' sysCONFIG Port Timing Specifications (3-36)
+ */
+#define MACHXO2_MAX_SPEED			66000000
+
+#define MACHXO2_LOW_DELAY			5		/* us */
+#define MACHXO2_HIGH_DELAY			200		/* us */
+#define MACHXO2_REFRESH				4800	/* us */
+#define MACHXO2_MAX_BUSY_LOOP		128
+#define MACHXO2_MAX_REFRESH_LOOP	16
+
+#define MACHXO2_PAGE_SIZE			16
+#define MACHXO2_BUF_SIZE			(MACHXO2_PAGE_SIZE + 4)
+
+/* Status register bits, errors and error mask */
+#define BUSY	12
+#define DONE	8
+#define DVER	27
+#define ENAB	9
+#define ERRBITS	23
+#define ERRMASK	7
+#define FAIL	13
+
+#define ENOERR	0 /* no error */
+#define EID		1
+#define ECMD	2
+#define	ECRC	3
+#define EPREAM	4 /* preamble error */
+#define EABRT	5 /* abort error */
+#define EOVERFL 6 /* overflow error */
+#define ESDMEOF 7 /* SDM EOF */
+
+static inline u8 get_err(unsigned long *status)
+{
+	return (*status >> ERRBITS) & ERRMASK;
+}
+
+static int get_status(struct spi_device *spi, unsigned long *status)
+{
+	struct spi_message msg;
+	struct spi_transfer rx, tx;
+	u8 cmd[] = LSC_READ_STATUS;
+	int ret;
+
+	memset(&rx, 0, sizeof(rx));
+	memset(&tx, 0, sizeof(tx));
+	tx.tx_buf = cmd;
+	tx.len = sizeof(cmd);
+	rx.rx_buf = status;
+	rx.len = 4;
+	spi_message_init(&msg);
+	spi_message_add_tail(&tx, &msg);
+	spi_message_add_tail(&rx, &msg);
+	ret = spi_sync(spi, &msg);
+	if (ret)
+		return ret;
+
+	*status = be32_to_cpu(*status);
+	return 0;
+}
+
+#ifdef DEBUG
+static void dump_status_reg(unsigned long *status)
+{
+	char *ferr;
+
+	switch (get_err(status)) {
+	case ENOERR:
+		ferr = "No Error";
+		break;
+	case EID:
+		ferr = "ID ERR";
+		break;
+	case ECMD:
+		ferr = "CMD ERR";
+		break;
+	case ECRC:
+		ferr = "CRC ERR";
+		break;
+	case EPREAM:
+		ferr = "Preamble ERR";
+		break;
+	case EABRT:
+		ferr = "Abort ERR";
+		break;
+	case EOVERFL:
+		ferr = "Overflow ERR";
+		break;
+	case ESDMEOF:
+		ferr = "SDM EOF";
+		break;
+	default:
+		ferr = "Default switch case";
+	}
+	pr_debug("machxo2 status: 0x%08lX - done=%d, cfgena=%d, busy=%d, fail=%d, devver=%d, err=%s\n",
+	       *status, test_bit(DONE, status), test_bit(ENAB, status),
+	       test_bit(BUSY, status), test_bit(FAIL, status),
+		   test_bit(DVER, status), ferr);
+}
+#else
+static void dump_status_reg(unsigned long *status) {}
+#endif
+
+static int wait_until_not_busy(struct spi_device *spi)
+{
+	unsigned long status;
+	int ret, loop = 0;
+
+	do {
+		ret = get_status(spi, &status);
+		if (ret)
+			break;
+		if (++loop >= MACHXO2_MAX_BUSY_LOOP) {
+			ret = -EBUSY;
+			break;
+		}
+	} while (test_bit(BUSY, &status));
+
+	return ret;
+}
+
+static int machxo2_cleanup(struct fpga_manager *mgr)
+{
+	struct spi_device *spi = mgr->priv;
+	struct spi_message msg;
+	struct spi_transfer tx[2];
+	u8 erase[] = ISC_ERASE;
+	u8 refresh[] = LSC_REFRESH;
+	int ret;
+
+	memset(tx, 0, sizeof(tx));
+	spi_message_init(&msg);
+	tx[0].tx_buf = &erase;
+	tx[0].len = sizeof(erase);
+	spi_message_add_tail(&tx[0], &msg);
+	ret = spi_sync(spi, &msg);
+	if (ret)
+		goto fail;
+
+	ret = wait_until_not_busy(spi);
+	if (ret)
+		goto fail;
+
+	spi_message_init(&msg);
+	tx[1].tx_buf = &refresh;
+	tx[1].len = sizeof(refresh);
+	tx[1].delay_usecs = MACHXO2_REFRESH;
+	spi_message_add_tail(&tx[1], &msg);
+	ret = spi_sync(spi, &msg);
+	if (ret)
+		goto fail;
+
+	return 0;
+fail:
+	dev_err(&mgr->dev, "Cleanup failed\n");
+	return ret;
+}
+
+static enum fpga_mgr_states machxo2_spi_state(struct fpga_manager *mgr)
+{
+	return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static int machxo2_write_init(struct fpga_manager *mgr,
+			      struct fpga_image_info *info,
+			      const char *buf, size_t count)
+{
+	struct spi_device *spi = mgr->priv;
+	struct spi_message msg;
+	struct spi_transfer tx[3];
+	u8 enable[] = ISC_ENABLE;
+	u8 erase[] = ISC_ERASE;
+	u8 initaddr[] = LSC_INITADDRESS;
+	unsigned long status;
+	int ret;
+
+	if ((info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
+		dev_err(&mgr->dev,
+			"Partial reconfiguration is not supported\n");
+		return -ENOTSUPP;
+	}
+
+	get_status(spi, &status);
+	dump_status_reg(&status);
+	memset(tx, 0, sizeof(tx));
+	spi_message_init(&msg);
+	tx[0].tx_buf = &enable;
+	tx[0].len = sizeof(enable);
+	tx[0].delay_usecs = MACHXO2_LOW_DELAY;
+	spi_message_add_tail(&tx[0], &msg);
+
+	tx[1].tx_buf = &erase;
+	tx[1].len = sizeof(erase);
+	spi_message_add_tail(&tx[1], &msg);
+	ret = spi_sync(spi, &msg);
+	if (ret)
+		goto fail;
+
+	ret = wait_until_not_busy(spi);
+	if (ret)
+		goto fail;
+
+	get_status(spi, &status);
+	if (test_bit(FAIL, &status))
+		goto fail;
+	dump_status_reg(&status);
+
+	spi_message_init(&msg);
+	tx[2].tx_buf = &initaddr;
+	tx[2].len = sizeof(initaddr);
+	spi_message_add_tail(&tx[2], &msg);
+	ret = spi_sync(spi, &msg);
+	if (ret)
+		goto fail;
+
+	get_status(spi, &status);
+	dump_status_reg(&status);
+	return 0;
+fail:
+	dev_err(&mgr->dev, "Error during FPGA init.\n");
+	return ret;
+}
+
+static int machxo2_write(struct fpga_manager *mgr, const char *buf,
+			 size_t count)
+{
+	struct spi_device *spi = mgr->priv;
+	struct spi_message msg;
+	struct spi_transfer tx;
+	u8 progincr[] = LSC_PROGINCRNV;
+	u8 payload[MACHXO2_BUF_SIZE];
+	unsigned long status;
+	int i, ret;
+
+	if (count % MACHXO2_PAGE_SIZE != 0) {
+		dev_err(&mgr->dev, "Malformed payload.\n");
+		return -EINVAL;
+	}
+	get_status(spi, &status);
+	dump_status_reg(&status);
+	memcpy(payload, &progincr, sizeof(progincr));
+	for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
+		memcpy(&payload[sizeof(progincr)], &buf[i], MACHXO2_PAGE_SIZE);
+		memset(&tx, 0, sizeof(tx));
+		spi_message_init(&msg);
+		tx.tx_buf = payload;
+		tx.len = MACHXO2_BUF_SIZE;
+		tx.delay_usecs = MACHXO2_HIGH_DELAY;
+		spi_message_add_tail(&tx, &msg);
+		ret = spi_sync(spi, &msg);
+		if (ret) {
+			dev_err(&mgr->dev, "Error loading the bitstream.\n");
+			return ret;
+		}
+	}
+	get_status(spi, &status);
+	dump_status_reg(&status);
+
+	return 0;
+}
+
+static int machxo2_write_complete(struct fpga_manager *mgr,
+				  struct fpga_image_info *info)
+{
+	struct spi_device *spi = mgr->priv;
+	struct spi_message msg;
+	struct spi_transfer tx[2];
+	u8 progdone[] = ISC_PROGRAMDONE;
+	u8 refresh[] = LSC_REFRESH;
+	unsigned long status;
+	int ret, refreshloop = 0;
+
+	memset(tx, 0, sizeof(tx));
+	spi_message_init(&msg);
+	tx[0].tx_buf = &progdone;
+	tx[0].len = sizeof(progdone);
+	spi_message_add_tail(&tx[0], &msg);
+	ret = spi_sync(spi, &msg);
+	if (ret)
+		goto fail;
+	ret = wait_until_not_busy(spi);
+	if (ret)
+		goto fail;
+
+	get_status(spi, &status);
+	dump_status_reg(&status);
+	if (!test_bit(DONE, &status)) {
+		machxo2_cleanup(mgr);
+		goto fail;
+	}
+
+	do {
+		spi_message_init(&msg);
+		tx[1].tx_buf = &refresh;
+		tx[1].len = sizeof(refresh);
+		tx[1].delay_usecs = MACHXO2_REFRESH;
+		spi_message_add_tail(&tx[1], &msg);
+		ret = spi_sync(spi, &msg);
+		if (ret)
+			goto fail;
+
+		/* check refresh status */
+		get_status(spi, &status);
+		dump_status_reg(&status);
+		if (!test_bit(BUSY, &status) && test_bit(DONE, &status) &&
+			get_err(&status) == ENOERR)
+				break;
+		if (++refreshloop == MACHXO2_MAX_REFRESH_LOOP) {
+			machxo2_cleanup(mgr);
+			goto fail;
+		}
+	} while (1);
+
+	get_status(spi, &status);
+	dump_status_reg(&status);
+	return 0;
+fail:
+	dev_err(&mgr->dev, "Refresh failed.\n");
+	return ret;
+}
+
+static const struct fpga_manager_ops machxo2_ops = {
+	.state = machxo2_spi_state,
+	.write_init = machxo2_write_init,
+	.write = machxo2_write,
+	.write_complete = machxo2_write_complete,
+};
+
+static int machxo2_spi_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+
+	if (spi->max_speed_hz > MACHXO2_MAX_SPEED) {
+		dev_err(dev, "Speed is too high\n");
+		return -EINVAL;
+	}
+
+	return fpga_mgr_register(dev, "Lattice MachXO2 SPI FPGA Manager",
+				 &machxo2_ops, spi);
+}
+
+static int machxo2_spi_remove(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+
+	fpga_mgr_unregister(dev);
+
+	return 0;
+}
+
+static const struct of_device_id of_match[] = {
+	{ .compatible = "lattice,machxo2-slave-spi", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, of_match);
+
+static const struct spi_device_id lattice_ids[] = {
+	{ "machxo2-slave-spi", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(spi, lattice_ids);
+
+static struct spi_driver machxo2_spi_driver = {
+	.driver = {
+		.name = "machxo2-slave-spi",
+		.of_match_table = of_match_ptr(of_match),
+	},
+	.probe = machxo2_spi_probe,
+	.remove = machxo2_spi_remove,
+	.id_table = lattice_ids,
+};
+
+module_spi_driver(machxo2_spi_driver)
+
+MODULE_AUTHOR("Paolo Pisati <p.pisati@gmail.com>");
+MODULE_DESCRIPTION("Load Lattice FPGA firmware over SPI");
+MODULE_LICENSE("GPL v2");