fmc-sdb: first implementation

kernel/fmc-sdb.c

+/*
+ * Copyright (C) 2012 CERN (www.cern.ch)
+ * Author: Alessandro Rubini <rubini@gnudd.com>
+ *
+ * Released according to the GNU GPL, version 2 or any later version.
+ *
+ * This work is part of the White Rabbit project, a research effort led
+ * by CERN, the European Institute for Nuclear Research.
+ */
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/fmc.h>
+#include <linux/sdb.h>
+#include <linux/err.h>
+#include <linux/fmc-sdb.h>
+#include <asm/byteorder.h>
+
+static uint32_t __sdb_rd(struct fmc_device *fmc, unsigned long address,
+			int convert)
+{
+	uint32_t res = fmc_readl(fmc, address);
+	if (convert)
+		return __be32_to_cpu(res);
+	return res;
+}
+
+static struct sdb_array *__fmc_scan_sdb_tree(struct fmc_device *fmc,
+					     unsigned long address, int level)
+{
+	uint32_t onew;
+	int i, j, n, convert = 0;
+	struct sdb_array *arr, *sub;
+
+	onew = fmc_readl(fmc, address);
+	if (onew == SDB_MAGIC) {
+		/* Uh! If we are little-endian, we must convert */
+		if (SDB_MAGIC != __be32_to_cpu(SDB_MAGIC))
+			convert = 1;
+	} else if (onew == __be32_to_cpu(SDB_MAGIC)) {
+		/* ok, don't convert */
+	} else {
+		return ERR_PTR(-ENOENT);
+	}
+	/* So, the magic was there: get the count from offset 4*/
+	onew = __sdb_rd(fmc, address + 4, convert);
+	n = __be16_to_cpu(*(uint16_t *)&onew);
+	dev_info(fmc->hwdev, "address %lx, %i items (%08x) - c %i\n", address,
+		 n, onew, convert);
+	arr = kzalloc(sizeof(*arr), GFP_KERNEL);
+	if (arr) {
+		arr->record = kzalloc(sizeof(arr->record[0]) * n, GFP_KERNEL);
+		arr->subtree = kzalloc(sizeof(arr->subtree[0]) * n, GFP_KERNEL);
+	}
+	if (!arr || !arr->record || !arr->subtree) {
+		kfree(arr->record);
+		kfree(arr->subtree);
+		kfree(arr);
+		return ERR_PTR(-ENOMEM);
+	}
+	arr->len = n;
+	arr->level = level;
+	arr->fmc = fmc;
+	for (i = 0; i < n; i++) {
+		for (j = 0; j < sizeof(arr->record[0]); j += 4) {
+			*(uint32_t *)((void *)(arr->record + i) + j) =
+				__sdb_rd(fmc, address + (i * 64) + j, convert);
+		}
+		arr->subtree[i] = ERR_PTR(-ENODEV);
+		if (arr->record[i].empty.record_type == sdb_type_bridge) {
+			uint64_t subaddr = arr->record[i].bridge.sdb_child;
+
+			subaddr = __be64_to_cpu(subaddr);
+			sub = __fmc_scan_sdb_tree(fmc, subaddr, level + 1);
+			arr->subtree[i] = sub; /* may be error */
+		}
+	}
+	return arr;
+}
+
+int fmc_scan_sdb_tree(struct fmc_device *fmc, unsigned long address)
+{
+	struct sdb_array *ret;
+	if (fmc->sdb)
+		return -EBUSY;
+	ret = __fmc_scan_sdb_tree(fmc, address, 0);
+	if (IS_ERR(ret))
+		return PTR_ERR(ret);
+	fmc->sdb = ret;
+	return 0;
+}
+EXPORT_SYMBOL(fmc_scan_sdb_tree);
+
+
+static void __fmc_show_sdb_tree(struct sdb_array *arr)
+{
+	int i, j, n = arr->len, level = arr->level;
+
+	for (i = 0; i < n; i++) {
+		union  sdb_record *r;
+		struct sdb_product *p;
+		struct sdb_component *c;
+		for (j = 0; j < level; j++)
+			printk("   ");
+		r = &arr->record[i];
+		c = &r->dev.sdb_component;
+		p = &c->product;
+
+		switch(r->empty.record_type) {
+		case sdb_type_interconnect:
+			printk("%08llx:%08x %.19s\n",
+			       __be64_to_cpu(p->vendor_id),
+			       __be32_to_cpu(p->device_id),
+			       p->name);
+			break;
+		case sdb_type_device:
+			printk("%08llx:%08x %.19s (%08llx-%08llx)\n",
+			       __be64_to_cpu(p->vendor_id),
+			       __be32_to_cpu(p->device_id),
+			       p->name,
+			       __be64_to_cpu(c->addr_first),
+			       __be64_to_cpu(c->addr_last));
+			break;
+		case sdb_type_bridge:
+			printk("%08llx:%08x %.19s (bridge)\n",
+			       __be64_to_cpu(p->vendor_id),
+			       __be32_to_cpu(p->device_id),
+			       p->name);
+			if (IS_ERR(arr->subtree[i])) {
+				printk("(bridge error %li)\n",
+				       PTR_ERR(arr->subtree[i]));
+				break;
+			}
+			__fmc_show_sdb_tree(arr->subtree[i]);
+			break;
+		case sdb_type_integration:
+			printk("integration\n");
+			break;
+		case sdb_type_empty:
+			printk("empty\n");
+			break;
+		default:
+			printk("UNKNOWN TYPE 0x%02x\n", r->empty.record_type);
+			break;
+		}
+	}
+}
+
+void fmc_show_sdb_tree(struct fmc_device *fmc)
+{
+	if (!fmc->sdb)
+		return;
+	__fmc_show_sdb_tree(fmc->sdb);
+}
+EXPORT_SYMBOL(fmc_show_sdb_tree);
+
+unsigned long fmc_find_sdb_device(struct sdb_array *tree)
+{
+	return 0;
+}