[U-Boot] [PATCH] fpga: zynq: Add delay after PCFG_PROG_B change

[U-Boot] [PATCH] fpga: zynq: Add delay after PCFG_PROG_B change

[Michal Simek]

From: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>

There is delay needed after PCFG_PROGB change if
AES key source is efuse. This fixes the issue of
encrypted bitstream loading with AES efuse as key
source.

Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
---

 drivers/fpga/zynqpl.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/fpga/zynqpl.c b/drivers/fpga/zynqpl.c
index 2ff716c25228..db9bd12992f9 100644
--- a/drivers/fpga/zynqpl.c
+++ b/drivers/fpga/zynqpl.c
@@ -17,6 +17,7 @@
 #include <asm/arch/sys_proto.h>
 
 #define DEVCFG_CTRL_PCFG_PROG_B		0x40000000
+#define DEVCFG_CTRL_PCFG_AES_EFUSE_MASK	0x00001000
 #define DEVCFG_ISR_FATAL_ERROR_MASK	0x00740040
 #define DEVCFG_ISR_ERROR_FLAGS_MASK	0x00340840
 #define DEVCFG_ISR_RX_FIFO_OV		0x00040000
@@ -205,9 +206,24 @@ static int zynq_dma_xfer_init(bitstream_type bstype)
 		/* Setting PCFG_PROG_B signal to high */
 		control = readl(&devcfg_base->ctrl);
 		writel(control | DEVCFG_CTRL_PCFG_PROG_B, &devcfg_base->ctrl);
+
+		/*
+		 * Delay is required if AES efuse is selected as
+		 * key source.
+		 */
+		if (control & DEVCFG_CTRL_PCFG_AES_EFUSE_MASK)
+			mdelay(5);
+
 		/* Setting PCFG_PROG_B signal to low */
 		writel(control & ~DEVCFG_CTRL_PCFG_PROG_B, &devcfg_base->ctrl);
 
+		/*
+		 * Delay is required if AES efuse is selected as
+		 * key source.
+		 */
+		if (control & DEVCFG_CTRL_PCFG_AES_EFUSE_MASK)
+			mdelay(5);
+
 		/* Polling the PCAP_INIT status for Reset */
 		ts = get_timer(0);
 		while (readl(&devcfg_base->status) & DEVCFG_STATUS_PCFG_INIT) {
-- 
1.9.1