[PATCH V4 XRT Alveo 12/20] fpga: xrt: VSEC platform driver

[Lizhi Hou]

Add VSEC driver. VSEC is a hardware function discovered by walking
PCI Express configure space. A platform device node will be created
for it. VSEC provides board logic UUID and few offset of other hardware
functions.

Signed-off-by: Sonal Santan <sonal.santan@xxxxxxxxxx>
Signed-off-by: Max Zhen <max.zhen@xxxxxxxxxx>
Signed-off-by: Lizhi Hou <lizhi.hou@xxxxxxxxxx>
---
 drivers/fpga/xrt/lib/xleaf/vsec.c | 388 ++++++++++++++++++++++++++++++
 1 file changed, 388 insertions(+)
 create mode 100644 drivers/fpga/xrt/lib/xleaf/vsec.c

diff --git a/drivers/fpga/xrt/lib/xleaf/vsec.c b/drivers/fpga/xrt/lib/xleaf/vsec.c
new file mode 100644
index 000000000000..8595d23f5710
--- /dev/null
+++ b/drivers/fpga/xrt/lib/xleaf/vsec.c
@@ -0,0 +1,388 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx Alveo FPGA VSEC Driver
+ *
+ * Copyright (C) 2020-2021 Xilinx, Inc.
+ *
+ * Authors:
+ *      Lizhi Hou<Lizhi.Hou@xxxxxxxxxx>
+ */
+
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include "metadata.h"
+#include "xleaf.h"
+
+#define XRT_VSEC "xrt_vsec"
+
+#define VSEC_TYPE_UUID		0x50
+#define VSEC_TYPE_FLASH		0x51
+#define VSEC_TYPE_PLATINFO	0x52
+#define VSEC_TYPE_MAILBOX	0x53
+#define VSEC_TYPE_END		0xff
+
+#define VSEC_UUID_LEN		16
+
+#define VSEC_REG_FORMAT		0x0
+#define VSEC_REG_LENGTH		0x4
+#define VSEC_REG_ENTRY		0x8
+
+struct xrt_vsec_header {
+	u32		format;
+	u32		length;
+	u32		entry_sz;
+	u32		rsvd;
+} __packed;
+
+struct xrt_vsec_entry {
+	u8		type;
+	u8		bar_rev;
+	u16		off_lo;
+	u32		off_hi;
+	u8		ver_type;
+	u8		minor;
+	u8		major;
+	u8		rsvd0;
+	u32		rsvd1;
+} __packed;
+
+struct vsec_device {
+	u8		type;
+	char		*ep_name;
+	ulong		size;
+	char		*regmap;
+};
+
+static struct vsec_device vsec_devs[] = {
+	{
+		.type = VSEC_TYPE_UUID,
+		.ep_name = XRT_MD_NODE_BLP_ROM,
+		.size = VSEC_UUID_LEN,
+		.regmap = "vsec-uuid",
+	},
+	{
+		.type = VSEC_TYPE_FLASH,
+		.ep_name = XRT_MD_NODE_FLASH_VSEC,
+		.size = 4096,
+		.regmap = "vsec-flash",
+	},
+	{
+		.type = VSEC_TYPE_PLATINFO,
+		.ep_name = XRT_MD_NODE_PLAT_INFO,
+		.size = 4,
+		.regmap = "vsec-platinfo",
+	},
+	{
+		.type = VSEC_TYPE_MAILBOX,
+		.ep_name = XRT_MD_NODE_MAILBOX_VSEC,
+		.size = 48,
+		.regmap = "vsec-mbx",
+	},
+};
+
+static const struct regmap_config vsec_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = 0x1000,
+};
+
+struct xrt_vsec {
+	struct platform_device	*pdev;
+	struct regmap		*regmap;
+	u32			length;
+
+	char			*metadata;
+	char			uuid[VSEC_UUID_LEN];
+	int			group;
+};
+
+static inline int vsec_read_entry(struct xrt_vsec *vsec, u32 index, struct xrt_vsec_entry *entry)
+{
+	int ret;
+
+	ret = regmap_bulk_read(vsec->regmap, sizeof(struct xrt_vsec_header) +
+			       index * sizeof(struct xrt_vsec_entry), entry,
+			       sizeof(struct xrt_vsec_entry) /
+			       vsec_regmap_config.reg_stride);
+
+	return ret;
+}
+
+static inline u32 vsec_get_bar(struct xrt_vsec_entry *entry)
+{
+	return ((entry)->bar_rev >> 4) & 0xf;
+}
+
+static inline u64 vsec_get_bar_off(struct xrt_vsec_entry *entry)
+{
+	return (entry)->off_lo | ((u64)(entry)->off_hi << 16);
+}
+
+static inline u32 vsec_get_rev(struct xrt_vsec_entry *entry)
+{
+	return (entry)->bar_rev & 0xf;
+}
+
+static char *type2epname(u32 type)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(vsec_devs); i++) {
+		if (vsec_devs[i].type == type)
+			return (vsec_devs[i].ep_name);
+	}
+
+	return NULL;
+}
+
+static ulong type2size(u32 type)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(vsec_devs); i++) {
+		if (vsec_devs[i].type == type)
+			return (vsec_devs[i].size);
+	}
+
+	return 0;
+}
+
+static char *type2regmap(u32 type)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(vsec_devs); i++) {
+		if (vsec_devs[i].type == type)
+			return (vsec_devs[i].regmap);
+	}
+
+	return NULL;
+}
+
+static int xrt_vsec_add_node(struct xrt_vsec *vsec,
+			     void *md_blob, struct xrt_vsec_entry *p_entry)
+{
+	struct xrt_md_endpoint ep;
+	char regmap_ver[64];
+	int ret;
+
+	if (!type2epname(p_entry->type))
+		return -EINVAL;
+
+	/*
+	 * VSEC may have more than 1 mailbox instance for the card
+	 * which has more than 1 physical function.
+	 * This is not supported for now. Assuming only one mailbox
+	 */
+
+	snprintf(regmap_ver, sizeof(regmap_ver) - 1, "%d-%d.%d.%d",
+		 p_entry->ver_type, p_entry->major, p_entry->minor,
+		 vsec_get_rev(p_entry));
+	ep.ep_name = type2epname(p_entry->type);
+	ep.bar = vsec_get_bar(p_entry);
+	ep.bar_off = vsec_get_bar_off(p_entry);
+	ep.size = type2size(p_entry->type);
+	ep.regmap = type2regmap(p_entry->type);
+	ep.regmap_ver = regmap_ver;
+	ret = xrt_md_add_endpoint(DEV(vsec->pdev), vsec->metadata, &ep);
+	if (ret)
+		xrt_err(vsec->pdev, "add ep failed, ret %d", ret);
+
+	return ret;
+}
+
+static int xrt_vsec_create_metadata(struct xrt_vsec *vsec)
+{
+	struct xrt_vsec_entry entry;
+	int i, ret;
+
+	ret = xrt_md_create(&vsec->pdev->dev, &vsec->metadata);
+	if (ret) {
+		xrt_err(vsec->pdev, "create metadata failed");
+		return ret;
+	}
+
+	for (i = 0; i * sizeof(entry) < vsec->length -
+	    sizeof(struct xrt_vsec_header); i++) {
+		ret = vsec_read_entry(vsec, i, &entry);
+		if (ret) {
+			xrt_err(vsec->pdev, "failed read entry %d, ret %d", i, ret);
+			goto fail;
+		}
+
+		if (entry.type == VSEC_TYPE_END)
+			break;
+		ret = xrt_vsec_add_node(vsec, vsec->metadata, &entry);
+		if (ret)
+			goto fail;
+	}
+
+	return 0;
+
+fail:
+	vfree(vsec->metadata);
+	vsec->metadata = NULL;
+	return ret;
+}
+
+static int xrt_vsec_leaf_call(struct platform_device *pdev, u32 cmd, void *arg)
+{
+	int ret = 0;
+
+	switch (cmd) {
+	case XRT_XLEAF_EVENT:
+		/* Does not handle any event. */
+		break;
+	default:
+		ret = -EINVAL;
+		xrt_err(pdev, "should never been called");
+		break;
+	}
+
+	return ret;
+}
+
+static int xrt_vsec_mapio(struct xrt_vsec *vsec)
+{
+	struct xrt_subdev_platdata *pdata = DEV_PDATA(vsec->pdev);
+	struct resource *res = NULL;
+	void __iomem *base = NULL;
+	const u64 *bar_off;
+	const u32 *bar;
+	u64 addr;
+	int ret;
+
+	if (!pdata || xrt_md_size(DEV(vsec->pdev), pdata->xsp_dtb) == XRT_MD_INVALID_LENGTH) {
+		xrt_err(vsec->pdev, "empty metadata");
+		return -EINVAL;
+	}
+
+	ret = xrt_md_get_prop(DEV(vsec->pdev), pdata->xsp_dtb, XRT_MD_NODE_VSEC,
+			      NULL, XRT_MD_PROP_BAR_IDX, (const void **)&bar, NULL);
+	if (ret) {
+		xrt_err(vsec->pdev, "failed to get bar idx, ret %d", ret);
+		return -EINVAL;
+	}
+
+	ret = xrt_md_get_prop(DEV(vsec->pdev), pdata->xsp_dtb, XRT_MD_NODE_VSEC,
+			      NULL, XRT_MD_PROP_OFFSET, (const void **)&bar_off, NULL);
+	if (ret) {
+		xrt_err(vsec->pdev, "failed to get bar off, ret %d", ret);
+		return -EINVAL;
+	}
+
+	xrt_info(vsec->pdev, "Map vsec at bar %d, offset 0x%llx",
+		 be32_to_cpu(*bar), be64_to_cpu(*bar_off));
+
+	xleaf_get_barres(vsec->pdev, &res, be32_to_cpu(*bar));
+	if (!res) {
+		xrt_err(vsec->pdev, "failed to get bar addr");
+		return -EINVAL;
+	}
+
+	addr = res->start + be64_to_cpu(*bar_off);
+
+	base = devm_ioremap(&vsec->pdev->dev, addr, vsec_regmap_config.max_register);
+	if (!base) {
+		xrt_err(vsec->pdev, "Map failed");
+		return -EIO;
+	}
+
+	vsec->regmap = devm_regmap_init_mmio(&vsec->pdev->dev, base, &vsec_regmap_config);
+	if (IS_ERR(vsec->regmap)) {
+		xrt_err(vsec->pdev, "regmap %pR failed", res);
+		return PTR_ERR(vsec->regmap);
+	}
+
+	ret = regmap_read(vsec->regmap, VSEC_REG_LENGTH, &vsec->length);
+	if (ret) {
+		xrt_err(vsec->pdev, "failed to read length %d", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int xrt_vsec_remove(struct platform_device *pdev)
+{
+	struct xrt_vsec	*vsec;
+
+	vsec = platform_get_drvdata(pdev);
+
+	if (vsec->group >= 0)
+		xleaf_destroy_group(pdev, vsec->group);
+	vfree(vsec->metadata);
+
+	return 0;
+}
+
+static int xrt_vsec_probe(struct platform_device *pdev)
+{
+	struct xrt_vsec	*vsec;
+	int ret = 0;
+
+	vsec = devm_kzalloc(&pdev->dev, sizeof(*vsec), GFP_KERNEL);
+	if (!vsec)
+		return -ENOMEM;
+
+	vsec->pdev = pdev;
+	vsec->group = -1;
+	platform_set_drvdata(pdev, vsec);
+
+	ret = xrt_vsec_mapio(vsec);
+	if (ret)
+		goto failed;
+
+	ret = xrt_vsec_create_metadata(vsec);
+	if (ret) {
+		xrt_err(pdev, "create metadata failed, ret %d", ret);
+		goto failed;
+	}
+	vsec->group = xleaf_create_group(pdev, vsec->metadata);
+	if (ret < 0) {
+		xrt_err(pdev, "create group failed, ret %d", vsec->group);
+		ret = vsec->group;
+		goto failed;
+	}
+
+	return 0;
+
+failed:
+	xrt_vsec_remove(pdev);
+
+	return ret;
+}
+
+static struct xrt_subdev_endpoints xrt_vsec_endpoints[] = {
+	{
+		.xse_names = (struct xrt_subdev_ep_names []){
+			{ .ep_name = XRT_MD_NODE_VSEC },
+			{ NULL },
+		},
+		.xse_min_ep = 1,
+	},
+	{ 0 },
+};
+
+static struct xrt_subdev_drvdata xrt_vsec_data = {
+	.xsd_dev_ops = {
+		.xsd_leaf_call = xrt_vsec_leaf_call,
+	},
+};
+
+static const struct platform_device_id xrt_vsec_table[] = {
+	{ XRT_VSEC, (kernel_ulong_t)&xrt_vsec_data },
+	{ },
+};
+
+static struct platform_driver xrt_vsec_driver = {
+	.driver = {
+		.name = XRT_VSEC,
+	},
+	.probe = xrt_vsec_probe,
+	.remove = xrt_vsec_remove,
+	.id_table = xrt_vsec_table,
+};
+
+XRT_LEAF_INIT_FINI_FUNC(XRT_SUBDEV_VSEC, vsec);
-- 
2.27.0