[RFC PATCH 2/2] fpga: zynq-fpga: Add support for readback of configuration registers
From: Appana Durga Kedareswara rao
Date: Tue Jul 03 2018 - 04:45:07 EST
This patch adds support for Read-back of
configuration registers in zynq.
Signed-off-by: Appana Durga Kedareswara rao <appana.durga.rao@xxxxxxxxxx>
---
drivers/fpga/zynq-fpga.c | 254 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 254 insertions(+)
diff --git a/drivers/fpga/zynq-fpga.c b/drivers/fpga/zynq-fpga.c
index 70b15b3..31d39f0 100644
--- a/drivers/fpga/zynq-fpga.c
+++ b/drivers/fpga/zynq-fpga.c
@@ -25,6 +25,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/mfd/syscon.h>
+#include <linux/mutex.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/pm.h>
@@ -127,6 +128,49 @@
/* Disable global resets */
#define FPGA_RST_NONE_MASK 0x0
+/* Configuration Registers */
+#define TYPE1_CRC_OFFSET 0x0
+#define TYPE1_FAR_OFFSET 0x1
+#define TYPE1_FDRI_OFFSET 0x2
+#define TYPE1_FDRO_OFFSET 0x3
+#define TYPE1_CMD_OFFSET 0x4
+#define TYPE1_CTRL0_OFFSET 0x5
+#define TYPE1_MASK_OFFSET 0x6
+#define TYPE1_STAT_OFFSET 0x7
+#define TYPE1_LOUT_OFFSET 0x8
+#define TYPE1_COR0_OFFSET 0x9
+#define TYPE1_MFWR_OFFSET 0xa
+#define TYPE1_CBC_OFFSET 0xb
+#define TYPE1_IDCODE_OFFSET 0xc
+#define TYPE1_AXSS_OFFSET 0xd
+#define TYPE1_COR1_OFFSET 0xe
+#define TYPE1_WBSTR_OFFSET 0x10
+#define TYPE1_TIMER_OFFSET 0x11
+#define TYPE1_BOOTSTS_OFFSET 0x16
+#define TYPE1_CTRL1_OFFSET 0x18
+#define TYPE1_BSPI_OFFSET 0x1f
+
+/* Masks for Configuration registers */
+#define RCFG_CMD_MASK 0x00000004
+#define START_CMD_MASK 0x00000005
+#define RCRC_CMD_MASK 0x00000007
+#define SHUTDOWN_CMD_MASK 0x0000000B
+#define DESYNC_WORD_MASK 0x0000000D
+#define BUSWIDTH_SYNCWORD_MASK 0x000000BB
+#define NOOP_WORD_MASK 0x20000000
+#define BUSWIDTH_DETECT_MASK 0x11220044
+#define SYNC_WORD_MASK 0xAA995566
+#define DUMMY_WORD_MASK 0xFFFFFFFF
+
+#define TYPE1_HDR_SHIFT 29
+#define TYPE1_REG_SHIFT 13
+#define TYPE1_OP_SHIFT 27
+#define TYPE1_OPCODE_NOOP 0
+#define TYPE1_OPCODE_READ 1
+#define TYPE1_OPCODE_WRITE 2
+
+#define CFGREG_SRCDMA_SIZE 0x40
+
struct zynq_fpga_priv {
int irq;
struct clk *clk;
@@ -140,6 +184,7 @@ struct zynq_fpga_priv {
struct scatterlist *cur_sg;
struct completion dma_done;
+ struct mutex mutex_lock;
};
static inline void zynq_fpga_write(struct zynq_fpga_priv *priv, u32 offset,
@@ -164,6 +209,15 @@ static inline void zynq_fpga_set_irq(struct zynq_fpga_priv *priv, u32 enable)
zynq_fpga_write(priv, INT_MASK_OFFSET, ~enable);
}
+static void zynq_fpga_dma_xfer(struct zynq_fpga_priv *priv, u32 srcaddr,
+ u32 srclen, u32 dstaddr, u32 dstlen)
+{
+ zynq_fpga_write(priv, DMA_SRC_ADDR_OFFSET, srcaddr);
+ zynq_fpga_write(priv, DMA_DST_ADDR_OFFSET, dstaddr);
+ zynq_fpga_write(priv, DMA_SRC_LEN_OFFSET, srclen);
+ zynq_fpga_write(priv, DMA_DEST_LEN_OFFSET, dstlen);
+}
+
/* Must be called with dma_lock held */
static void zynq_step_dma(struct zynq_fpga_priv *priv)
{
@@ -546,12 +600,211 @@ static enum fpga_mgr_states zynq_fpga_ops_state(struct fpga_manager *mgr)
return FPGA_MGR_STATE_UNKNOWN;
}
+static int zynq_type1_pkt(u8 reg, u8 opcode, u16 size)
+{
+ /*
+ * Type 1 Packet Header Format
+ * The header section is always a 32-bit word.
+ *
+ * HeaderType | Opcode | Register Address | Reserved | Word Count
+ * [31:29] [28:27] [26:13] [12:11] [10:0]
+ * --------------------------------------------------------------
+ * 001 xx RRRRRRRRRxxxxx RR xxxxxxxxxxx
+ *
+ * @R: means the bit is not used and reserved for future use.
+ * The reserved bits should be written as 0s.
+ *
+ * Generating the Type 1 packet header which involves sifting of Type1
+ * Header Mask, Register value and the OpCode which is 01 in this case
+ * as only read operation is to be carried out and then performing OR
+ * operation with the Word Length.
+ */
+ return (((1 << TYPE1_HDR_SHIFT) |
+ (reg << TYPE1_REG_SHIFT) |
+ (opcode << TYPE1_OP_SHIFT)) | size);
+
+}
+
+static int zynq_fpga_getconfigreg(struct fpga_manager *mgr, u8 reg)
+{
+ struct zynq_fpga_priv *priv;
+ int ret = 0, cmdindex, src_offset;
+ int *srcbuf, *dstbuf;
+ dma_addr_t src_dma_addr, dst_dma_addr;
+ u32 status, intr_status;
+
+ priv = mgr->priv;
+
+ srcbuf = dma_alloc_coherent(mgr->dev.parent, CFGREG_SRCDMA_SIZE,
+ &src_dma_addr, GFP_KERNEL);
+ if (!srcbuf)
+ return -ENOMEM;
+
+ dstbuf = dma_alloc_coherent(mgr->dev.parent, sizeof(dstbuf),
+ &dst_dma_addr, GFP_KERNEL);
+ if (!dstbuf)
+ goto free_srcbuf;
+
+ cmdindex = 0;
+ srcbuf[cmdindex++] = DUMMY_WORD_MASK;
+ srcbuf[cmdindex++] = BUSWIDTH_SYNCWORD_MASK;
+ srcbuf[cmdindex++] = BUSWIDTH_DETECT_MASK;
+ srcbuf[cmdindex++] = DUMMY_WORD_MASK;
+ srcbuf[cmdindex++] = SYNC_WORD_MASK;
+ srcbuf[cmdindex++] = NOOP_WORD_MASK;
+ srcbuf[cmdindex++] = zynq_type1_pkt(reg, TYPE1_OPCODE_READ, 1);
+ srcbuf[cmdindex++] = NOOP_WORD_MASK;
+ srcbuf[cmdindex++] = NOOP_WORD_MASK;
+
+ ret = zynq_fpga_poll_timeout(priv, STATUS_OFFSET, status,
+ status & STATUS_PCFG_INIT_MASK,
+ INIT_POLL_DELAY,
+ INIT_POLL_TIMEOUT);
+ if (ret) {
+ dev_err(&mgr->dev, "Timeout waiting for PCFG_INIT\n");
+ goto free_dstbuf;
+ }
+
+ intr_status = zynq_fpga_read(priv, INT_STS_OFFSET);
+ zynq_fpga_write(priv, INT_STS_OFFSET, IXR_ALL_MASK);
+
+ zynq_fpga_dma_xfer(priv, src_dma_addr, cmdindex,
+ DMA_INVALID_ADDRESS, 0);
+ ret = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, status,
+ status & IXR_D_P_DONE_MASK,
+ INIT_POLL_DELAY,
+ INIT_POLL_TIMEOUT);
+ if (ret) {
+ dev_err(&mgr->dev, "Timeout waiting for D_P_DONE\n");
+ goto free_dstbuf;
+ }
+ zynq_fpga_set_irq(priv, intr_status);
+ zynq_fpga_dma_xfer(priv, DMA_INVALID_ADDRESS, 0, dst_dma_addr, 1);
+ ret = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, status,
+ status & IXR_DMA_DONE_MASK,
+ INIT_POLL_DELAY,
+ INIT_POLL_TIMEOUT);
+ if (ret) {
+ dev_err(&mgr->dev, "Timeout waiting for DMA DONE\n");
+ goto free_dstbuf;
+ }
+ ret = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, status,
+ status & IXR_D_P_DONE_MASK,
+ INIT_POLL_DELAY,
+ INIT_POLL_TIMEOUT);
+ if (ret) {
+ dev_err(&mgr->dev, "Timeout waiting for D_P_DONE\n");
+ goto free_dstbuf;
+ }
+ src_offset = cmdindex * 4;
+ cmdindex = 0;
+ srcbuf[cmdindex++] = zynq_type1_pkt(TYPE1_CMD_OFFSET,
+ TYPE1_OPCODE_WRITE, 1);
+ srcbuf[cmdindex++] = DESYNC_WORD_MASK;
+ srcbuf[cmdindex++] = NOOP_WORD_MASK;
+ srcbuf[cmdindex++] = NOOP_WORD_MASK;
+ zynq_fpga_dma_xfer(priv, src_dma_addr + src_offset, cmdindex,
+ DMA_INVALID_ADDRESS, 0);
+ ret = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, status,
+ status & IXR_DMA_DONE_MASK,
+ INIT_POLL_DELAY,
+ INIT_POLL_TIMEOUT);
+ if (ret) {
+ dev_err(&mgr->dev, "Timeout waiting for DMA DONE\n");
+ goto free_dstbuf;
+ }
+ ret = zynq_fpga_poll_timeout(priv, INT_STS_OFFSET, status,
+ status & IXR_D_P_DONE_MASK,
+ INIT_POLL_DELAY,
+ INIT_POLL_TIMEOUT);
+ if (ret) {
+ dev_err(&mgr->dev, "Timeout waiting for D_P_DONE\n");
+ goto free_dstbuf;
+ }
+
+ ret = *dstbuf;
+
+free_dstbuf:
+ dma_free_coherent(mgr->dev.parent, sizeof(dstbuf), dstbuf,
+ dst_dma_addr);
+free_srcbuf:
+ dma_free_coherent(mgr->dev.parent, CFGREG_SRCDMA_SIZE, srcbuf,
+ src_dma_addr);
+
+ return ret;
+}
+
+static int zynq_fpga_ops_read(struct fpga_manager *mgr, struct seq_file *s)
+{
+ struct zynq_fpga_priv *priv;
+ int err;
+
+ priv = mgr->priv;
+
+ if (!mutex_trylock(&priv->mutex_lock))
+ return -EBUSY;
+
+ err = clk_enable(priv->clk);
+ if (err)
+ goto err_unlock;
+
+ seq_puts(s, "zynq FPGA Configuration register contents are\n");
+ seq_printf(s, "CRC --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_CRC_OFFSET)));
+ seq_printf(s, "FAR --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_FAR_OFFSET)));
+ seq_printf(s, "FDRI --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_FDRI_OFFSET)));
+ seq_printf(s, "FDRO --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_FDRO_OFFSET)));
+ seq_printf(s, "CMD --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_CMD_OFFSET)));
+ seq_printf(s, "CTRL0 --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_CTRL0_OFFSET)));
+ seq_printf(s, "MASK --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_MASK_OFFSET)));
+ seq_printf(s, "STAT --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_STAT_OFFSET)));
+ seq_printf(s, "LOUT --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_LOUT_OFFSET)));
+ seq_printf(s, "COR0 --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_COR0_OFFSET)));
+ seq_printf(s, "MFWR --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_MFWR_OFFSET)));
+ seq_printf(s, "CBC --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_CBC_OFFSET)));
+ seq_printf(s, "IDCODE --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_IDCODE_OFFSET)));
+ seq_printf(s, "AXSS --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_AXSS_OFFSET)));
+ seq_printf(s, "COR1 --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_COR1_OFFSET)));
+ seq_printf(s, "WBSTR --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_WBSTR_OFFSET)));
+ seq_printf(s, "TIMER --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_TIMER_OFFSET)));
+ seq_printf(s, "BOOTSTS --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_BOOTSTS_OFFSET)));
+ seq_printf(s, "CTRL1 --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_CTRL1_OFFSET)));
+ seq_printf(s, "BSPI --> \t %x \t\r\n",
+ (zynq_fpga_getconfigreg(mgr, TYPE1_BSPI_OFFSET)));
+
+ clk_disable(priv->clk);
+
+err_unlock:
+ mutex_unlock(&priv->mutex_lock);
+
+ return 0;
+}
+
static const struct fpga_manager_ops zynq_fpga_ops = {
.initial_header_size = 128,
.state = zynq_fpga_ops_state,
.write_init = zynq_fpga_ops_write_init,
.write_sg = zynq_fpga_ops_write,
.write_complete = zynq_fpga_ops_write_complete,
+ .read = zynq_fpga_ops_read,
};
static int zynq_fpga_probe(struct platform_device *pdev)
@@ -565,6 +818,7 @@ static int zynq_fpga_probe(struct platform_device *pdev)
if (!priv)
return -ENOMEM;
spin_lock_init(&priv->dma_lock);
+ mutex_init(&priv->mutex_lock);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
priv->io_base = devm_ioremap_resource(dev, res);
--
2.7.4