[PATCHv5 6/8] fpga: add intel stratix10 soc fpga manager driver

From: richard . gong
Date: Thu May 24 2018 - 11:37:50 EST


From: Alan Tull <atull@xxxxxxxxxx>

Add driver for reconfiguring Intel Stratix10 SoC FPGA devices.
This driver communicates through the Intel Service Driver which
does communication with privileged hardware (that does the
FPGA programming) through a secure mailbox.

Signed-off-by: Alan Tull <atull@xxxxxxxxxx>
Signed-off-by: Richard Gong <richard.gong@xxxxxxxxx>
---
v2: this patch is added in patch set version 2
v3: change to align to the update of service client APIs, and the
update of fpga_mgr device node
v4: changes to align with stratix10-svc-client API updates
add Richard's signed-off-by
v5: update to align changes at service layer to minimize service
layer thread usages
---
drivers/fpga/Kconfig | 6 +
drivers/fpga/Makefile | 1 +
drivers/fpga/stratix10-soc.c | 545 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 552 insertions(+)
create mode 100644 drivers/fpga/stratix10-soc.c

diff --git a/drivers/fpga/Kconfig b/drivers/fpga/Kconfig
index f47ef84..1624a73 100644
--- a/drivers/fpga/Kconfig
+++ b/drivers/fpga/Kconfig
@@ -57,6 +57,12 @@ config FPGA_MGR_ZYNQ_FPGA
help
FPGA manager driver support for Xilinx Zynq FPGAs.

+config FPGA_MGR_STRATIX10_SOC
+ tristate "Intel Stratix10 SoC FPGA Manager"
+ depends on (ARCH_STRATIX10 && STRATIX10_SERVICE)
+ help
+ FPGA manager driver support for the Intel Stratix10 SoC.
+
config FPGA_MGR_XILINX_SPI
tristate "Xilinx Configuration over Slave Serial (SPI)"
depends on SPI
diff --git a/drivers/fpga/Makefile b/drivers/fpga/Makefile
index 3cb276a..6eef670 100644
--- a/drivers/fpga/Makefile
+++ b/drivers/fpga/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_FPGA_MGR_ALTERA_PS_SPI) += altera-ps-spi.o
obj-$(CONFIG_FPGA_MGR_ICE40_SPI) += ice40-spi.o
obj-$(CONFIG_FPGA_MGR_SOCFPGA) += socfpga.o
obj-$(CONFIG_FPGA_MGR_SOCFPGA_A10) += socfpga-a10.o
+obj-$(CONFIG_FPGA_MGR_STRATIX10_SOC) += stratix10-soc.o
obj-$(CONFIG_FPGA_MGR_TS73XX) += ts73xx-fpga.o
obj-$(CONFIG_FPGA_MGR_XILINX_SPI) += xilinx-spi.o
obj-$(CONFIG_FPGA_MGR_ZYNQ_FPGA) += zynq-fpga.o
diff --git a/drivers/fpga/stratix10-soc.c b/drivers/fpga/stratix10-soc.c
new file mode 100644
index 0000000..d645ef7
--- /dev/null
+++ b/drivers/fpga/stratix10-soc.c
@@ -0,0 +1,545 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * FPGA Manager Driver for Intel Stratix10 SoC
+ *
+ * Copyright (C) 2018 Intel Corporation
+ */
+#include <linux/completion.h>
+#include <linux/fpga/fpga-mgr.h>
+#include <linux/stratix10-svc-client.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+/*
+ * FPGA programming requires a higher level of privilege (EL3), per the SoC
+ * design.
+ */
+#define NUM_SVC_BUFS 4
+#define SVC_BUF_SIZE SZ_512K
+
+/* Indicates buffer is in use if set */
+#define SVC_BUF_LOCK 0
+
+/**
+ * struct s10_svc_buf
+ * @buf: virtual address of buf provided by service layer
+ * @lock: locked if buffer is in use
+ */
+struct s10_svc_buf {
+ char *buf;
+ unsigned long lock;
+};
+
+struct s10_priv {
+ struct stratix10_svc_chan *chan;
+ struct stratix10_svc_client client;
+ struct completion status_return_completion;
+ struct s10_svc_buf svc_bufs[NUM_SVC_BUFS];
+ unsigned long status;
+};
+
+static int s10_svc_send_msg(struct s10_priv *priv,
+ enum stratix10_svc_command_code command,
+ void *payload, u32 payload_length)
+{
+ struct stratix10_svc_chan *chan = priv->chan;
+ struct stratix10_svc_client_msg msg;
+ int ret;
+
+ pr_debug("%s cmd=%d payload=%p legnth=%d\n",
+ __func__, command, payload, payload_length);
+
+ msg.command = command;
+ msg.payload = payload;
+ msg.payload_length = payload_length;
+
+ ret = stratix10_svc_send(chan, &msg);
+ pr_debug("stratix10_svc_send returned status %d\n", ret);
+
+ return ret;
+}
+
+/**
+ * s10_free_buffers
+ * Free buffers allocated from the service layer's pool that are not in use.
+ * @mgr: fpga manager struct
+ * Free all buffers that are not in use.
+ * Return true when all buffers are freed.
+ */
+static bool s10_free_buffers(struct fpga_manager *mgr)
+{
+ struct s10_priv *priv = mgr->priv;
+ uint num_free = 0;
+ uint i;
+
+ for (i = 0; i < NUM_SVC_BUFS; i++) {
+ if (!priv->svc_bufs[i].buf) {
+ num_free++;
+ continue;
+ }
+
+ if (!test_and_set_bit_lock(SVC_BUF_LOCK,
+ &priv->svc_bufs[i].lock)) {
+ stratix10_svc_free_memory(priv->chan,
+ priv->svc_bufs[i].buf);
+ priv->svc_bufs[i].buf = NULL;
+ num_free++;
+ }
+ }
+
+ return num_free == NUM_SVC_BUFS;
+}
+
+/**
+ * s10_free_buffer_count
+ * Count how many buffers are not in use.
+ * @mgr: fpga manager struct
+ * Return # of buffers that are not in use.
+ */
+static uint s10_free_buffer_count(struct fpga_manager *mgr)
+{
+ struct s10_priv *priv = mgr->priv;
+ uint num_free = 0;
+ uint i;
+
+ for (i = 0; i < NUM_SVC_BUFS; i++)
+ if (!priv->svc_bufs[i].buf)
+ num_free++;
+
+ return num_free;
+}
+
+/**
+ * s10_unlock_bufs
+ * Given the returned buffer address, match that address to our buffer struct
+ * and unlock that buffer. This marks it as available to be refilled and sent
+ * (or freed).
+ * @priv: private data
+ * @kaddr: kernel address of buffer that was returned from service layer
+ */
+static void s10_unlock_bufs(struct s10_priv *priv, void *kaddr)
+{
+ uint i;
+
+ if (!kaddr)
+ return;
+
+ for (i = 0; i < NUM_SVC_BUFS; i++)
+ if (priv->svc_bufs[i].buf == kaddr) {
+ clear_bit_unlock(SVC_BUF_LOCK,
+ &priv->svc_bufs[i].lock);
+ return;
+ }
+
+ WARN(1, "Unknown buffer returned from service layer %p\n", kaddr);
+}
+
+/**
+ * s10_receive_callback
+ * Callback for service layer to use to provide client (this driver) messages
+ * received through the mailbox.
+ * @client: service layer client struct
+ * @data: message
+ */
+static void s10_receive_callback(struct stratix10_svc_client *client,
+ struct stratix10_svc_cb_data *data)
+{
+ struct s10_priv *priv = client->priv;
+ u32 status;
+ int i;
+
+ WARN_ONCE(!data, "%s: stratix10_svc_rc_data = NULL", __func__);
+
+ status = data->status;
+
+ /*
+ * Here we set status bits as we receive them. Elsewhere, we always use
+ * test_and_clear_bit() to check status in priv->status
+ */
+ for (i = 0; i <= SVC_STATUS_RECONFIG_ERROR; i++)
+ if (status & (1 << i))
+ set_bit(i, &priv->status);
+
+ if (status & BIT(SVC_STATUS_RECONFIG_BUFFER_DONE)) {
+ s10_unlock_bufs(priv, data->kaddr1);
+ s10_unlock_bufs(priv, data->kaddr2);
+ s10_unlock_bufs(priv, data->kaddr3);
+ }
+
+ complete(&priv->status_return_completion);
+}
+
+/**
+ * s10_ops_write_init
+ * Prepare for FPGA reconfiguration by requesting partial reconfig and
+ * allocating buffers from the service layer.
+ * @mgr: fpga manager
+ * @info: fpga image info
+ * @buf: fpga image buffer
+ * @count: size of buf in bytes
+ */
+static int s10_ops_write_init(struct fpga_manager *mgr,
+ struct fpga_image_info *info,
+ const char *buf, size_t count)
+{
+ struct s10_priv *priv = mgr->priv;
+ struct device *dev = priv->client.dev;
+ unsigned long timeout;
+ struct stratix10_svc_command_reconfig_payload payload;
+ char *kbuf;
+ uint i;
+ int ret;
+
+ if (info->flags & FPGA_MGR_PARTIAL_RECONFIG) {
+ dev_info(dev, "Requesting partial reconfiguration.\n");
+ payload.flags |= BIT(COMMAND_RECONFIG_FLAG_PARTIAL);
+ } else {
+ dev_info(dev, "Requesting full reconfiguration.\n");
+ }
+
+ reinit_completion(&priv->status_return_completion);
+ ret = s10_svc_send_msg(priv, COMMAND_RECONFIG,
+ &payload, sizeof(payload));
+ if (ret)
+ goto init_done;
+
+ timeout = msecs_to_jiffies(SVC_RECONFIG_REQUEST_TIMEOUT_MS);
+ ret = wait_for_completion_interruptible_timeout(
+ &priv->status_return_completion, timeout);
+ if (!ret) {
+ dev_err(dev, "timeout waiting for RECONFIG_REQUEST\n");
+ ret = -ETIMEDOUT;
+ goto init_done;
+ }
+ if (ret < 0) {
+ dev_err(dev, "error (%d) waiting for RECONFIG_REQUEST\n", ret);
+ goto init_done;
+ }
+
+ ret = 0;
+ if (!test_and_clear_bit(SVC_STATUS_RECONFIG_REQUEST_OK,
+ &priv->status)) {
+ ret = -ETIMEDOUT;
+ goto init_done;
+ }
+
+ /* Allocate buffers from the service layer's pool. */
+ for (i = 0; i < NUM_SVC_BUFS; i++) {
+ kbuf = stratix10_svc_allocate_memory(priv->chan, SVC_BUF_SIZE);
+ if (!kbuf) {
+ s10_free_buffers(mgr);
+ ret = -ENOMEM;
+ goto init_done;
+ }
+
+ priv->svc_bufs[i].buf = kbuf;
+ priv->svc_bufs[i].lock = 0;
+ }
+
+init_done:
+ stratix10_svc_done(priv->chan);
+ return ret;
+}
+
+/**
+ * s10_send_buf
+ * Send a buffer to the service layer queue
+ * @mgr: fpga manager struct
+ * @buf_num: index of buffer in svc_bufs array
+ * @buf: fpga image buffer
+ * @count: size of buf in bytes
+ * Returns # of bytes transferred or -errno, never 0
+ */
+static int s10_send_buf(struct fpga_manager *mgr, uint buf_num,
+ const char *buf, size_t count)
+
+{
+ struct s10_priv *priv = mgr->priv;
+ struct device *dev = priv->client.dev;
+ void *svc_buf;
+ size_t xfer_sz;
+ int ret;
+
+ xfer_sz = count < SVC_BUF_SIZE ? count : SVC_BUF_SIZE;
+
+ svc_buf = priv->svc_bufs[buf_num].buf;
+ memcpy(svc_buf, buf, xfer_sz);
+ ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_DATA_SUBMIT,
+ svc_buf, xfer_sz);
+ if (ret) {
+ dev_err(dev,
+ "Error while sending data to service layer (%d)", ret);
+ return ret;
+ }
+
+ return xfer_sz;
+}
+
+/**
+ * s10_ops_write
+ * Send a FPGA image to privileged layers to write to the FPGA. When done
+ * sending, free all service layer buffers we allocated in write_init.
+ * @mgr: fpga manager
+ * @buf: fpga image buffer
+ * @count: size of buf in bytes
+ * Returns 0 for success or negative errno.
+ */
+static int s10_ops_write(struct fpga_manager *mgr, const char *buf,
+ size_t count)
+{
+ struct s10_priv *priv = mgr->priv;
+ struct device *dev = priv->client.dev;
+ unsigned long timeout;
+ size_t sent = 0;
+ int ret = 0;
+ uint i;
+
+ timeout = msecs_to_jiffies(SVC_RECONFIG_BUFFER_TIMEOUT_MS);
+
+ /* Buffer loop: either send buffers or free them. */
+ while (1) {
+ reinit_completion(&priv->status_return_completion);
+
+ if (count > 0) {
+ for (i = 0; i < NUM_SVC_BUFS; i++)
+ if (!test_and_set_bit_lock(
+ SVC_BUF_LOCK, &priv->svc_bufs[i].lock))
+ break;
+
+ if (i == NUM_SVC_BUFS)
+ /* wait for a free buffer */
+ continue;
+
+ sent = s10_send_buf(mgr, i, buf, count);
+ /*
+ * If service queue was full, we won't get a callback.
+ * Wait and try again
+ */
+ if (sent < 0)
+ continue;
+
+ count -= sent;
+ buf += sent;
+ } else {
+ s10_free_buffers(mgr);
+ if (s10_free_buffer_count(mgr) == NUM_SVC_BUFS)
+ return 0;
+
+ ret = s10_svc_send_msg(
+ priv, COMMAND_RECONFIG_DATA_CLAIM,
+ NULL, 0);
+ if (ret)
+ break;
+ }
+
+ /*
+ * If callback hasn't already happened, wait for buffers to be
+ * returned from service layer
+ */
+ if (priv->status)
+ ret = 0;
+ else
+ ret = wait_for_completion_interruptible_timeout(
+ &priv->status_return_completion, timeout);
+
+ if (test_and_clear_bit(
+ SVC_STATUS_RECONFIG_BUFFER_DONE, &priv->status))
+ continue;
+
+ if (test_and_clear_bit(SVC_STATUS_RECONFIG_BUFFER_SUBMITTED,
+ &priv->status))
+ continue;
+
+ if (test_and_clear_bit(SVC_STATUS_RECONFIG_ERROR,
+ &priv->status)) {
+ dev_err(dev, "ERROR - giving up - SVC_STATUS_RECONFIG_ERROR\n");
+ ret = -EFAULT;
+ break;
+ }
+
+ if (!ret) {
+ dev_err(dev, "timeout waiting for svc layer buffers\n");
+ ret = -ETIMEDOUT;
+ break;
+ }
+ if (ret < 0) {
+ dev_err(dev,
+ "error (%d) waiting for svc layer buffers\n",
+ ret);
+ break;
+ }
+ }
+
+ s10_free_buffers(mgr);
+ if (s10_free_buffer_count(mgr) != NUM_SVC_BUFS)
+ dev_err(dev, "%s not all buffers were freed\n", __func__);
+
+ return ret;
+}
+
+/**
+ * s10_ops_write_complete
+ * Wait for FPGA configuration to be done
+ * @mgr: fpga manager
+ * @info: fpga image info
+ * Returns 0 for success negative errno.
+ */
+static int s10_ops_write_complete(struct fpga_manager *mgr,
+ struct fpga_image_info *info)
+{
+ struct s10_priv *priv = mgr->priv;
+ struct device *dev = priv->client.dev;
+ unsigned long timeout;
+ int ret;
+
+ timeout = usecs_to_jiffies(info->config_complete_timeout_us);
+
+ do {
+ reinit_completion(&priv->status_return_completion);
+
+ ret = s10_svc_send_msg(priv, COMMAND_RECONFIG_STATUS, NULL, 0);
+ if (ret)
+ break;
+
+ ret = wait_for_completion_interruptible_timeout(
+ &priv->status_return_completion, timeout);
+ if (!ret) {
+ dev_err(dev,
+ "timeout waiting for RECONFIG_COMPLETED\n");
+ ret = -ETIMEDOUT;
+ break;
+ }
+ if (ret < 0) {
+ dev_err(dev,
+ "error (%d) waiting for RECONFIG_COMPLETED\n",
+ ret);
+ break;
+ }
+ /* Not error or timeout, so ret is # of jiffies until timeout */
+ timeout = ret;
+ ret = 0;
+
+ if (test_and_clear_bit(SVC_STATUS_RECONFIG_COMPLETED,
+ &priv->status))
+ break;
+
+ if (test_and_clear_bit(SVC_STATUS_RECONFIG_ERROR,
+ &priv->status)) {
+ dev_err(dev, "ERROR - giving up - SVC_STATUS_RECONFIG_ERROR\n");
+ ret = -EFAULT;
+ break;
+ }
+ } while (1);
+
+ stratix10_svc_done(priv->chan);
+ return ret;
+}
+
+static enum fpga_mgr_states s10_ops_state(struct fpga_manager *mgr)
+{
+ return FPGA_MGR_STATE_UNKNOWN;
+}
+
+static const struct fpga_manager_ops s10_ops = {
+ .state = s10_ops_state,
+ .write_init = s10_ops_write_init,
+ .write = s10_ops_write,
+ .write_complete = s10_ops_write_complete,
+};
+
+static int s10_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct s10_priv *priv;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->client.dev = dev;
+ priv->client.receive_cb = s10_receive_callback;
+ priv->client.priv = priv;
+
+ priv->chan = stratix10_svc_request_channel_byname(&priv->client,
+ SVC_CLIENT_FPGA);
+ if (IS_ERR(priv->chan)) {
+ dev_err(dev, "couldn't get service channel (%s)\n",
+ SVC_CLIENT_FPGA);
+ return PTR_ERR(priv->chan);
+ }
+
+ init_completion(&priv->status_return_completion);
+
+ ret = fpga_mgr_register(dev, "Stratix10 SOC FPGA Manager",
+ &s10_ops, priv);
+
+ if (ret)
+ stratix10_svc_free_channel(priv->chan);
+
+ return ret;
+}
+
+static int s10_remove(struct platform_device *pdev)
+{
+ struct fpga_manager *mgr = platform_get_drvdata(pdev);
+ struct s10_priv *priv = mgr->priv;
+
+ fpga_mgr_unregister(&pdev->dev);
+ stratix10_svc_free_channel(priv->chan);
+
+ return 0;
+}
+
+static const struct of_device_id s10_of_match[] = {
+ { .compatible = "intel,stratix10-soc-fpga-mgr", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, s10_of_match);
+
+static struct platform_driver s10_driver = {
+ .probe = s10_probe,
+ .remove = s10_remove,
+ .driver = {
+ .name = "Stratix10 SoC FPGA manager",
+ .of_match_table = of_match_ptr(s10_of_match),
+ },
+};
+
+static int __init s10_init(void)
+{
+ struct device_node *fw_np;
+ struct device_node *np;
+ int ret;
+
+ fw_np = of_find_node_by_name(NULL, "svc");
+ if (!fw_np)
+ return -ENODEV;
+
+ np = of_find_matching_node(fw_np, s10_of_match);
+ if (!np) {
+ of_node_put(fw_np);
+ return -ENODEV;
+ }
+
+ of_node_put(np);
+ ret = of_platform_populate(fw_np, s10_of_match, NULL, NULL);
+ of_node_put(fw_np);
+ if (ret)
+ return ret;
+
+ return platform_driver_register(&s10_driver);
+}
+
+static void __exit s10_exit(void)
+{
+ return platform_driver_unregister(&s10_driver);
+}
+
+module_init(s10_init);
+module_exit(s10_exit);
+
+MODULE_AUTHOR("Alan Tull <atull@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Intel Stratix 10 SOC FPGA Manager");
+MODULE_LICENSE("GPL v2");
--
2.7.4