FPGA Manager changes for 7.4-rc1

- Uwe drops unnecessary header file for fpga-dfl driver
 - Heiko corrects GPIO controls for xilinx driver
 - Hemanth fixes a comment typo in altera driver
 - Karl fixes a code comment in fpga manager core
 - Nazim introduces a graceful error handling for altera driver
 
 All patches have been reviewed on the mailing list, and have been in the
 last linux-next releases (as part of our for-next branch).
 
 Signed-off-by: Xu Yilun <yilun.xu@intel.com>
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Merge tag 'fpga-for-7.4-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/fpga/linux-fpga into char-misc-next

Xu writes:

FPGA Manager changes for 7.4-rc1

- Uwe drops unnecessary header file for fpga-dfl driver
- Heiko corrects GPIO controls for xilinx driver
- Hemanth fixes a comment typo in altera driver
- Karl fixes a code comment in fpga manager core
- Nazim introduces a graceful error handling for altera driver

All patches have been reviewed on the mailing list, and have been in the
last linux-next releases (as part of our for-next branch).

Signed-off-by: Xu Yilun <yilun.xu@intel.com>

* tag 'fpga-for-7.4-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/fpga/linux-fpga:
  fpga: altera-cvp: Retry teardown and reset CVP state on failure
  fpga: altera-cvp: Add helper to disable CvP mode
  fpga: Fix of_fpga_mgr_get() reference in fpga_mgr_lock() docs
  fpga: fix typo in s10_ops_write() comment
  fpga: xilinx-selectmap: control CSI_B and RDWR_B during configuration
  fpga: dfl: Drop #include for <linux/mod_devicetable.h>

drivers/fpga/altera-cvp.c

@@ -280,6 +280,16 @@ static int altera_cvp_send_block(struct altera_cvp_conf *conf,
 	return 0;
 }
 
+static void altera_cvp_disable_cvp_mode(struct altera_cvp_conf *conf)
+{
+	u32 val;
+
+	altera_read_config_dword(conf, VSE_CVP_MODE_CTRL, &val);
+	val &= ~VSE_CVP_MODE_CTRL_HIP_CLK_SEL;
+	val &= ~VSE_CVP_MODE_CTRL_CVP_MODE;
+	altera_write_config_dword(conf, VSE_CVP_MODE_CTRL, val);
+}
+
 static int altera_cvp_teardown(struct fpga_manager *mgr,
 			       struct fpga_image_info *info)
 {
@@ -308,7 +318,29 @@ static int altera_cvp_teardown(struct fpga_manager *mgr,
 	ret = altera_cvp_wait_status(conf, VSE_CVP_STATUS_CFG_RDY, 0,
 				     conf->priv->poll_time_us);
 	if (ret)
-		dev_err(&mgr->dev, "CFG_RDY == 0 timeout\n");
+		dev_warn(&mgr->dev, "CFG_RDY == 0 timeout\n");
+
+	return ret;
+}
+
+static int altera_cvp_recovery(struct fpga_manager *mgr,
+			       struct fpga_image_info *info)
+{
+	struct altera_cvp_conf *conf = mgr->priv;
+	int ret;
+
+	ret = altera_cvp_teardown(mgr, info);
+	if (ret) {
+		/*
+		 * CVP_STATUS may get stuck if the device left user mode
+		 * before the poll. Exit CvP mode to switch back the clock
+		 * feeding CVP_STATUS, then try the teardown again.
+		 */
+		altera_cvp_disable_cvp_mode(conf);
+		ret = altera_cvp_teardown(mgr, info);
+		if (ret)
+			dev_err(&mgr->dev, "Tear-down failed\n");
+	}
 
 	return ret;
 }
@@ -345,7 +377,7 @@ static int altera_cvp_write_init(struct fpga_manager *mgr,
 
 	if (val & VSE_CVP_STATUS_CFG_RDY) {
 		dev_warn(&mgr->dev, "CvP already started, tear down first\n");
-		ret = altera_cvp_teardown(mgr, info);
+		ret = altera_cvp_recovery(mgr, info);
 		if (ret)
 			return ret;
 	}
@@ -486,7 +518,7 @@ static int altera_cvp_write_complete(struct fpga_manager *mgr,
 	u32 mask, val;
 	int ret;
 
-	ret = altera_cvp_teardown(mgr, info);
+	ret = altera_cvp_recovery(mgr, info);
 	if (ret)
 		return ret;
 
@@ -498,10 +530,7 @@ static int altera_cvp_write_complete(struct fpga_manager *mgr,
 	}
 
 	/* STEP 17 - reset CVP_MODE and HIP_CLK_SEL bit */
-	altera_read_config_dword(conf, VSE_CVP_MODE_CTRL, &val);
-	val &= ~VSE_CVP_MODE_CTRL_HIP_CLK_SEL;
-	val &= ~VSE_CVP_MODE_CTRL_CVP_MODE;
-	altera_write_config_dword(conf, VSE_CVP_MODE_CTRL, val);
+	altera_cvp_disable_cvp_mode(conf);
 
 	/* STEP 18 - poll PLD_CLK_IN_USE and USER_MODE bits */
 	mask = VSE_CVP_STATUS_PLD_CLK_IN_USE | VSE_CVP_STATUS_USERMODE;

drivers/fpga/dfl.h

@@ -23,7 +23,6 @@
 #include <linux/interrupt.h>
 #include <linux/iopoll.h>
 #include <linux/io-64-nonatomic-lo-hi.h>
-#include <linux/mod_devicetable.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/uuid.h>

drivers/fpga/fpga-mgr.c

@@ -744,7 +744,7 @@ EXPORT_SYMBOL_GPL(fpga_mgr_put);
  * @mgr:	fpga manager
  *
  * Given a pointer to FPGA Manager (from fpga_mgr_get() or
- * of_fpga_mgr_put()) attempt to get the mutex. The user should call
+ * of_fpga_mgr_get()) attempt to get the mutex. The user should call
  * fpga_mgr_lock() and verify that it returns 0 before attempting to
  * program the FPGA.  Likewise, the user should call fpga_mgr_unlock
  * when done programming the FPGA.

drivers/fpga/stratix10-soc.c

@@ -286,7 +286,7 @@ static int s10_ops_write(struct fpga_manager *mgr, const char *buf,
 
 	/*
 	 * Loop waiting for buffers to be returned.  When a buffer is returned,
-	 * reuse it to send more data or free if if all data has been sent.
+	 * reuse it to send more data or free it if all data has been sent.
 	 */
 	while (count > 0 || s10_free_buffer_count(mgr) != NUM_SVC_BUFS) {
 		reinit_completion(&priv->status_return_completion);

drivers/fpga/xilinx-selectmap.c

@@ -19,6 +19,8 @@
 struct xilinx_selectmap_conf {
 	struct xilinx_fpga_core core;
 	void __iomem *base;
+	struct gpio_desc *csi_b;
+	struct gpio_desc *rdwr_b;
 };
 
 #define to_xilinx_selectmap_conf(obj) \
@@ -30,16 +32,28 @@ static int xilinx_selectmap_write(struct xilinx_fpga_core *core,
 	struct xilinx_selectmap_conf *conf = to_xilinx_selectmap_conf(core);
 	size_t i;
 
+	/*
+	 * Select this device and put its SelectMAP port into write mode.
+	 *
+	 * RDWR_B is set before CSI_B. UG470 describes in chapter
+	 * "SelectMAP ABORT" that changing RDWR_B while the device is
+	 * selected aborts the configuration on the next CCLK.
+	 */
+	gpiod_set_value(conf->rdwr_b, 1);
+	gpiod_set_value(conf->csi_b, 1);
+
 	for (i = 0; i < count; ++i)
 		writeb(buf[i], conf->base);
 
+	gpiod_set_value(conf->csi_b, 0);
+	gpiod_set_value(conf->rdwr_b, 0);
+
 	return 0;
 }
 
 static int xilinx_selectmap_probe(struct platform_device *pdev)
 {
 	struct xilinx_selectmap_conf *conf;
-	struct gpio_desc *gpio;
 	void __iomem *base;
 
 	conf = devm_kzalloc(&pdev->dev, sizeof(*conf), GFP_KERNEL);
@@ -55,16 +69,23 @@ static int xilinx_selectmap_probe(struct platform_device *pdev)
 				     "ioremap error\n");
 	conf->base = base;
 
-	/* CSI_B is active low */
-	gpio = devm_gpiod_get_optional(&pdev->dev, "csi", GPIOD_OUT_HIGH);
-	if (IS_ERR(gpio))
-		return dev_err_probe(&pdev->dev, PTR_ERR(gpio),
+	/*
+	 * Request both signals deasserted, so a device sharing the SelectMAP
+	 * bus with others stays off that bus until its bitstream is written.
+	 *
+	 * The value in the gpiod flags is logical, gpiolib drives the line
+	 * high for GPIOD_OUT_LOW when the firmware describes it active low.
+	 */
+	conf->csi_b = devm_gpiod_get_optional(&pdev->dev, "csi",
+					      GPIOD_OUT_LOW);
+	if (IS_ERR(conf->csi_b))
+		return dev_err_probe(&pdev->dev, PTR_ERR(conf->csi_b),
 				     "Failed to get CSI_B gpio\n");
 
-	/* RDWR_B is active low */
-	gpio = devm_gpiod_get_optional(&pdev->dev, "rdwr", GPIOD_OUT_HIGH);
-	if (IS_ERR(gpio))
-		return dev_err_probe(&pdev->dev, PTR_ERR(gpio),
+	conf->rdwr_b = devm_gpiod_get_optional(&pdev->dev, "rdwr",
+					       GPIOD_OUT_LOW);
+	if (IS_ERR(conf->rdwr_b))
+		return dev_err_probe(&pdev->dev, PTR_ERR(conf->rdwr_b),
 				     "Failed to get RDWR_B gpio\n");
 
 	return xilinx_core_probe(&conf->core);