2017-06-15 11:13:10

by Paolo Pisati

[permalink] [raw]
Subject: [PATCH v3 0/2] [RESEND] Lattice MachXO2 Slave SPI FPGA Manager support

Hi all,

this series adds support for the Lattice MachXO2 FPGA chip, programmed
over Slave SPI.

Tested on my raspberry pi3 + bugblat's pif2 fpga hat.

Changes from v1:
* fixed all the warnings pointed out by 'checkpatch --strict' and
Alan Tull

Changes from v2:
* convert to BIT() macro and spi_message_init() / trans.delay_usecs

Paolo Pisati (2):
dt: bindings: fpga: add lattice machxo2 slave spi binding description
fpga: lattice machxo2: Add Lattice MachXO2 support

.../bindings/fpga/lattice-machxo2-spi.txt | 29 +++
drivers/fpga/Kconfig | 7 +
drivers/fpga/Makefile | 1 +
drivers/fpga/machxo2-spi.c | 277 +++++++++++++++++++++
4 files changed, 314 insertions(+)
create mode 100644 Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt
create mode 100644 drivers/fpga/machxo2-spi.c

--
2.7.4


2017-06-15 11:13:40

by Paolo Pisati

[permalink] [raw]
Subject: [PATCH v3 1/2] dt: bindings: fpga: add lattice machxo2 slave spi binding description

Add dt binding documentation details for Lattice MachXO2 FPGA configuration
over Slave SPI interface.

Signed-off-by: Paolo Pisati <[email protected]>
Acked-by: Rob Herring <[email protected]>
---
.../bindings/fpga/lattice-machxo2-spi.txt | 29 ++++++++++++++++++++++
1 file changed, 29 insertions(+)
create mode 100644 Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt

diff --git a/Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt b/Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt
new file mode 100644
index 0000000..c3ef26bd
--- /dev/null
+++ b/Documentation/devicetree/bindings/fpga/lattice-machxo2-spi.txt
@@ -0,0 +1,29 @@
+Lattice MachXO2 Slave SPI FPGA Manager
+
+Lattice MachXO2 FPGAs support a method of loading the bitstream over
+'slave SPI' interface.
+
+See 'MachXO2ProgrammingandConfigurationUsageGuide.pdf' on http://www.latticesemi.com
+
+Required properties:
+- compatible: should contain "lattice,machxo2-slave-spi"
+- reg: spi chip select of the FPGA
+
+Example for full FPGA configuration:
+
+ fpga-region0 {
+ compatible = "fpga-region";
+ fpga-mgr = <&fpga_mgr_spi>;
+ #address-cells = <0x1>;
+ #size-cells = <0x1>;
+ };
+
+ spi1: spi@2000 {
+ ...
+
+ fpga_mgr_spi: fpga-mgr@0 {
+ compatible = "lattice,machxo2-slave-spi";
+ spi-max-frequency = <60000000>;
+ reg = <0>;
+ };
+ };
--
2.7.4

2017-06-15 11:13:15

by Paolo Pisati

[permalink] [raw]
Subject: [PATCH v3 2/2] fpga: lattice machxo2: Add Lattice MachXO2 support

This patch adds support to the FPGA manager for programming
MachXO2 device’s internal flash memory, via slave SPI.

Signed-off-by: Paolo Pisati <[email protected]>
---
drivers/fpga/Kconfig | 7 ++
drivers/fpga/Makefile | 1 +
drivers/fpga/machxo2-spi.c | 277 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 285 insertions(+)
create mode 100644 drivers/fpga/machxo2-spi.c

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index c81cb7d..cce135b 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -26,6 +26,13 @@ config FPGA_MGR_ICE40_SPI
help
FPGA manager driver support for Lattice iCE40 FPGAs 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 c6f5d74..cdab1fe 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_FPGA) += fpga-mgr.o

# FPGA Manager Drivers
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..ea8793c
--- /dev/null
+++ b/drivers/fpga/machxo2-spi.c
@@ -0,0 +1,277 @@
+/**
+ * Lattice MachXO2 Slave SPI Driver
+ *
+ * Copyright (C) 2017 Paolo Pisati <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * Manage Lattice FPGA firmware that is loaded over SPI using
+ * the slave serial configuration interface.
+ */
+
+#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 ISC_DISABLE 0x00000026
+#define ISC_ENABLE 0x000008c6
+#define ISC_ERASE 0x0000040e
+#define ISC_NOOP 0xffffffff
+#define ISC_PROGRAMDONE 0x0000005e
+#define LSC_CHECKBUSY 0x000000f0
+#define LSC_INITADDRESS 0x00000046
+#define LSC_PROGINCRNV 0x01000070
+#define LSC_REFRESH 0x00000079
+
+#define BUSYFLAG BIT(7)
+
+/*
+ * 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_OP_SIZE sizeof(u32)
+#define MACHXO2_PAGE_SIZE 16
+#define MACHXO2_BUF_SIZE (MACHXO2_OP_SIZE + MACHXO2_PAGE_SIZE)
+
+static int wait_until_not_busy(struct spi_device *spi)
+{
+ struct spi_message msg;
+ struct spi_transfer rx, tx;
+ u32 checkbusy = LSC_CHECKBUSY;
+ u8 busy;
+ int ret;
+
+ do {
+ memset(&rx, 0, sizeof(rx));
+ memset(&tx, 0, sizeof(tx));
+ tx.tx_buf = &checkbusy;
+ tx.len = MACHXO2_OP_SIZE;
+ rx.rx_buf = &busy;
+ rx.len = sizeof(busy);
+ 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;
+ } while (busy & BUSYFLAG);
+
+ return 0;
+}
+
+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[5];
+ u32 disable = ISC_DISABLE;
+ u32 bypass = ISC_NOOP;
+ u32 enable = ISC_ENABLE;
+ u32 erase = ISC_ERASE;
+ u32 initaddr = LSC_INITADDRESS;
+ int ret;
+
+ if ((info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
+ dev_err(&mgr->dev,
+ "Partial reconfiguration is not supported\n");
+ return -ENOTSUPP;
+ }
+
+ memset(tx, 0, sizeof(tx));
+ spi_message_init(&msg);
+ tx[0].tx_buf = &disable;
+ tx[0].len = MACHXO2_OP_SIZE - 1;
+ spi_message_add_tail(&tx[0], &msg);
+
+ tx[1].tx_buf = &bypass;
+ tx[1].len = MACHXO2_OP_SIZE;
+ 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;
+
+ spi_message_init(&msg);
+ tx[2].tx_buf = &enable;
+ tx[2].len = MACHXO2_OP_SIZE;
+ tx[2].delay_usecs = MACHXO2_LOW_DELAY;
+ spi_message_add_tail(&tx[2], &msg);
+
+ tx[3].tx_buf = &erase;
+ tx[3].len = MACHXO2_OP_SIZE;
+ spi_message_add_tail(&tx[3], &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[4].tx_buf = &initaddr;
+ tx[4].len = MACHXO2_OP_SIZE;
+ spi_message_add_tail(&tx[4], &msg);
+ ret = spi_sync(spi, &msg);
+ if (ret)
+ goto fail;
+
+ 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;
+ u32 progincr = LSC_PROGINCRNV;
+ u8 payload[MACHXO2_BUF_SIZE];
+ int i, ret;
+
+ if (count % MACHXO2_PAGE_SIZE != 0) {
+ dev_err(&mgr->dev, "Malformed payload.\n");
+ return -EINVAL;
+ }
+
+ memcpy(payload, &progincr, MACHXO2_OP_SIZE);
+ for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
+ memcpy(&payload[MACHXO2_OP_SIZE], &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;
+ }
+ }
+
+ 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];
+ u32 progdone = ISC_PROGRAMDONE;
+ u32 refresh = LSC_REFRESH;
+ int ret;
+
+ memset(tx, 0, sizeof(tx));
+ spi_message_init(&msg);
+ tx[0].tx_buf = &progdone;
+ tx[0].len = MACHXO2_OP_SIZE;
+ 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 = MACHXO2_OP_SIZE - 1;
+ 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, "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 <[email protected]>");
+MODULE_DESCRIPTION("Load Lattice FPGA firmware over SPI");
+MODULE_LICENSE("GPL v2");
--
2.7.4

2017-06-15 20:03:46

by Moritz Fischer

[permalink] [raw]
Subject: Re: [PATCH v3 2/2] fpga: lattice machxo2: Add Lattice MachXO2 support

On Thu, Jun 15, 2017 at 4:13 AM, Paolo Pisati <[email protected]> wrote:
> This patch adds support to the FPGA manager for programming
> MachXO2 device’s internal flash memory, via slave SPI.
>
> Signed-off-by: Paolo Pisati <[email protected]>
> ---
> drivers/fpga/Kconfig | 7 ++
> drivers/fpga/Makefile | 1 +
> drivers/fpga/machxo2-spi.c | 277 +++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 285 insertions(+)
> create mode 100644 drivers/fpga/machxo2-spi.c
>
> diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
> index c81cb7d..cce135b 100644
> --- a/drivers/fpga/Kconfig
> +++ b/drivers/fpga/Kconfig
> @@ -26,6 +26,13 @@ config FPGA_MGR_ICE40_SPI
> help
> FPGA manager driver support for Lattice iCE40 FPGAs 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 c6f5d74..cdab1fe 100644
> --- a/drivers/fpga/Makefile
> +++ b/drivers/fpga/Makefile
> @@ -7,6 +7,7 @@ obj-$(CONFIG_FPGA) += fpga-mgr.o
>
> # FPGA Manager Drivers
> obj-$(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..ea8793c
> --- /dev/null
> +++ b/drivers/fpga/machxo2-spi.c
> @@ -0,0 +1,277 @@
> +/**
> + * Lattice MachXO2 Slave SPI Driver
> + *
> + * Copyright (C) 2017 Paolo Pisati <[email protected]>
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + *
> + * Manage Lattice FPGA firmware that is loaded over SPI using
> + * the slave serial configuration interface.
> + */
> +
> +#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 ISC_DISABLE 0x00000026
> +#define ISC_ENABLE 0x000008c6
> +#define ISC_ERASE 0x0000040e
> +#define ISC_NOOP 0xffffffff
> +#define ISC_PROGRAMDONE 0x0000005e
> +#define LSC_CHECKBUSY 0x000000f0
> +#define LSC_INITADDRESS 0x00000046
> +#define LSC_PROGINCRNV 0x01000070
> +#define LSC_REFRESH 0x00000079
> +
> +#define BUSYFLAG BIT(7)
> +
> +/*
> + * 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_OP_SIZE sizeof(u32)
> +#define MACHXO2_PAGE_SIZE 16
> +#define MACHXO2_BUF_SIZE (MACHXO2_OP_SIZE + MACHXO2_PAGE_SIZE)
> +
> +static int wait_until_not_busy(struct spi_device *spi)
> +{
> + struct spi_message msg;
> + struct spi_transfer rx, tx;
> + u32 checkbusy = LSC_CHECKBUSY;
> + u8 busy;
> + int ret;
> +
> + do {
> + memset(&rx, 0, sizeof(rx));
> + memset(&tx, 0, sizeof(tx));
> + tx.tx_buf = &checkbusy;
> + tx.len = MACHXO2_OP_SIZE;
> + rx.rx_buf = &busy;
> + rx.len = sizeof(busy);
> + 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;
> + } while (busy & BUSYFLAG);
> +
> + return 0;
> +}
> +
> +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[5];
> + u32 disable = ISC_DISABLE;
> + u32 bypass = ISC_NOOP;
> + u32 enable = ISC_ENABLE;
> + u32 erase = ISC_ERASE;
> + u32 initaddr = LSC_INITADDRESS;
> + int ret;
> +
> + if ((info->flags & FPGA_MGR_PARTIAL_RECONFIG)) {
> + dev_err(&mgr->dev,
> + "Partial reconfiguration is not supported\n");
> + return -ENOTSUPP;
> + }
> +
> + memset(tx, 0, sizeof(tx));
> + spi_message_init(&msg);
> + tx[0].tx_buf = &disable;
> + tx[0].len = MACHXO2_OP_SIZE - 1;
> + spi_message_add_tail(&tx[0], &msg);
> +
> + tx[1].tx_buf = &bypass;
> + tx[1].len = MACHXO2_OP_SIZE;
> + 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;
> +
> + spi_message_init(&msg);
> + tx[2].tx_buf = &enable;
> + tx[2].len = MACHXO2_OP_SIZE;
> + tx[2].delay_usecs = MACHXO2_LOW_DELAY;
> + spi_message_add_tail(&tx[2], &msg);
> +
> + tx[3].tx_buf = &erase;
> + tx[3].len = MACHXO2_OP_SIZE;
> + spi_message_add_tail(&tx[3], &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[4].tx_buf = &initaddr;
> + tx[4].len = MACHXO2_OP_SIZE;
> + spi_message_add_tail(&tx[4], &msg);
> + ret = spi_sync(spi, &msg);
> + if (ret)
> + goto fail;
> +
> + 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;
> + u32 progincr = LSC_PROGINCRNV;
> + u8 payload[MACHXO2_BUF_SIZE];
> + int i, ret;
> +
> + if (count % MACHXO2_PAGE_SIZE != 0) {
> + dev_err(&mgr->dev, "Malformed payload.\n");
> + return -EINVAL;
> + }
> +
> + memcpy(payload, &progincr, MACHXO2_OP_SIZE);
> + for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
> + memcpy(&payload[MACHXO2_OP_SIZE], &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;
> + }
> + }

Can't you chain them together and submit it as one? Instead of calling
spi_sync in a loop?
You don't seem to wait for _wait_until_not_busy, so wouldn't that work?

> +
> + 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];
> + u32 progdone = ISC_PROGRAMDONE;
> + u32 refresh = LSC_REFRESH;
> + int ret;
> +
> + memset(tx, 0, sizeof(tx));
> + spi_message_init(&msg);
> + tx[0].tx_buf = &progdone;
> + tx[0].len = MACHXO2_OP_SIZE;
> + 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 = MACHXO2_OP_SIZE - 1;
> + 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, "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 <[email protected]>");
> +MODULE_DESCRIPTION("Load Lattice FPGA firmware over SPI");
> +MODULE_LICENSE("GPL v2");
> --
> 2.7.4
>

Thanks,
Moritz

2017-06-16 09:04:43

by Paolo Pisati

[permalink] [raw]
Subject: Re: [PATCH v3 2/2] fpga: lattice machxo2: Add Lattice MachXO2 support

On Thu, Jun 15, 2017 at 01:03:41PM -0700, Moritz Fischer wrote:
> > +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;
> > + u32 progincr = LSC_PROGINCRNV;
> > + u8 payload[MACHXO2_BUF_SIZE];
> > + int i, ret;
> > +
> > + if (count % MACHXO2_PAGE_SIZE != 0) {
> > + dev_err(&mgr->dev, "Malformed payload.\n");
> > + return -EINVAL;
> > + }
> > +
> > + memcpy(payload, &progincr, MACHXO2_OP_SIZE);
> > + for (i = 0; i < count; i += MACHXO2_PAGE_SIZE) {
> > + memcpy(&payload[MACHXO2_OP_SIZE], &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;
> > + }
> > + }
>
> Can't you chain them together and submit it as one? Instead of calling
> spi_sync in a loop?
> You don't seem to wait for _wait_until_not_busy, so wouldn't that work?

I could unroll the loop, or i could move from a static delay
(MACHXO2_HIGH_DELAY) to checking the busy flag if we want to make it faster, not
sure which one i prefer, or if it's worth though.
--
bye,
p.