drivers: Introduce MEN Chameleon Bus

The MCB (MEN Chameleon Bus) is a Bus specific to MEN Mikroelektronik
FPGA based devices. It is used to identify MCB based IP-Cores within
an FPGA and provide the necessary framework for instantiating drivers
for these devices.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@men.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 159 insertions, 0 deletions

diff --git a/drivers/mcb/mcb-parse.c b/drivers/mcb/mcb-parse.c
new file mode 100644
index 0000000..d1278b5
--- /dev/null
+++ b/drivers/mcb/mcb-parse.c
@@ -0,0 +1,159 @@
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/io.h>
+#include <linux/mcb.h>
+
+#include "mcb-internal.h"
+
+struct mcb_parse_priv {
+	phys_addr_t mapbase;
+	void __iomem *base;
+};
+
+#define for_each_chameleon_cell(dtype, p)	\
+	for ((dtype) = get_next_dtype((p));	\
+	     (dtype) != CHAMELEON_DTYPE_END;	\
+	     (dtype) = get_next_dtype((p)))
+
+static inline uint32_t get_next_dtype(void __iomem *p)
+{
+	uint32_t dtype;
+
+	dtype = readl(p);
+	return dtype >> 28;
+}
+
+static int chameleon_parse_bdd(struct mcb_bus *bus,
+			phys_addr_t mapbase,
+			void __iomem *base)
+{
+	return 0;
+}
+
+static int chameleon_parse_gdd(struct mcb_bus *bus,
+			phys_addr_t mapbase,
+			void __iomem *base)
+{
+	struct chameleon_gdd __iomem *gdd =
+		(struct chameleon_gdd __iomem *) base;
+	struct mcb_device *mdev;
+	u32 offset;
+	u32 size;
+	int ret;
+	__le32 reg1;
+	__le32 reg2;
+
+	mdev = mcb_alloc_dev(bus);
+	if (!mdev)
+		return -ENOMEM;
+
+	reg1 = readl(&gdd->reg1);
+	reg2 = readl(&gdd->reg2);
+	offset = readl(&gdd->offset);
+	size = readl(&gdd->size);
+
+	mdev->id = GDD_DEV(reg1);
+	mdev->rev = GDD_REV(reg1);
+	mdev->var = GDD_VAR(reg1);
+	mdev->bar = GDD_BAR(reg1);
+	mdev->group = GDD_GRP(reg2);
+	mdev->inst = GDD_INS(reg2);
+
+	pr_debug("Found a 16z%03d\n", mdev->id);
+
+	mdev->irq.start = GDD_IRQ(reg1);
+	mdev->irq.end = GDD_IRQ(reg1);
+	mdev->irq.flags = IORESOURCE_IRQ;
+
+	mdev->mem.start = mapbase + offset;
+	mdev->mem.end = mdev->mem.start + size - 1;
+	mdev->mem.flags = IORESOURCE_MEM;
+
+	mdev->is_added = false;
+
+	ret = mcb_device_register(bus, mdev);
+	if (ret < 0)
+		goto err;
+
+	return 0;
+
+err:
+	mcb_free_dev(mdev);
+
+	return ret;
+}
+
+int chameleon_parse_cells(struct mcb_bus *bus, phys_addr_t mapbase,
+			void __iomem *base)
+{
+	char __iomem *p = base;
+	struct chameleon_fpga_header *header;
+	uint32_t dtype;
+	int num_cells = 0;
+	int ret = 0;
+	u32 hsize;
+
+	hsize = sizeof(struct chameleon_fpga_header);
+
+	header = kzalloc(hsize, GFP_KERNEL);
+	if (!header)
+		return -ENOMEM;
+
+	/* Extract header information */
+	memcpy_fromio(header, p, hsize);
+	/* We only support chameleon v2 at the moment */
+	header->magic = le16_to_cpu(header->magic);
+	if (header->magic != CHAMELEONV2_MAGIC) {
+		pr_err("Unsupported chameleon version 0x%x\n",
+				header->magic);
+		kfree(header);
+		return -ENODEV;
+	}
+	p += hsize;
+
+	pr_debug("header->revision = %d\n", header->revision);
+	pr_debug("header->model = 0x%x ('%c')\n", header->model,
+		header->model);
+	pr_debug("header->minor = %d\n", header->minor);
+	pr_debug("header->bus_type = 0x%x\n", header->bus_type);
+
+
+	pr_debug("header->magic = 0x%x\n", header->magic);
+	pr_debug("header->filename = \"%.*s\"\n", CHAMELEON_FILENAME_LEN,
+		header->filename);
+
+	for_each_chameleon_cell(dtype, p) {
+		switch (dtype) {
+		case CHAMELEON_DTYPE_GENERAL:
+			ret = chameleon_parse_gdd(bus, mapbase, p);
+			if (ret < 0)
+				goto out;
+			p += sizeof(struct chameleon_gdd);
+			break;
+		case CHAMELEON_DTYPE_BRIDGE:
+			chameleon_parse_bdd(bus, mapbase, p);
+			p += sizeof(struct chameleon_bdd);
+			break;
+		case CHAMELEON_DTYPE_END:
+			break;
+		default:
+			pr_err("Invalid chameleon descriptor type 0x%x\n",
+				dtype);
+			return -EINVAL;
+		}
+		num_cells++;
+	}
+
+	if (num_cells == 0)
+		num_cells = -EINVAL;
+
+	kfree(header);
+	return num_cells;
+
+out:
+	kfree(header);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(chameleon_parse_cells);