mcb: Added bar descriptor support for non PCI bus MCB carrier

Added support for the bar descriptor. This type is used for FPGAs
connect to the LPC or to a non PCI bus.

The Bar descriptor could have a maximum of 6 BARs. Each of the
devices within the FPGA could be mapped to a different BAR.
The BAR descriptor is comparable to the PCI header.

Signed-off-by: Andreas Werner <andreas.werner@men.de>
[ free bar descriptor in the non-error case ]
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 121 insertions, 14 deletions

diff --git a/drivers/mcb/mcb-internal.h b/drivers/mcb/mcb-internal.h
index 5254e0285725..d6e6933b19f1 100644
--- a/drivers/mcb/mcb-internal.h
+++ b/drivers/mcb/mcb-internal.h
@@ -112,6 +112,15 @@ struct chameleon_bdd {
         u32 size;
 } __packed;
 
+struct chameleon_bar {
+        u32 addr;
+        u32 size;
+};
+
+#define BAR_CNT(x) ((x) & 0x07)
+#define CHAMELEON_BAR_MAX       6
+#define BAR_DESC_SIZE(x)        ((x) * sizeof(struct chameleon_bar) + sizeof(__le32))
+
 int chameleon_parse_cells(struct mcb_bus *bus, phys_addr_t mapbase,
                           void __iomem *base);
 
diff --git a/drivers/mcb/mcb-parse.c b/drivers/mcb/mcb-parse.c
index dbecbed0d258..4ca2739b4fad 100644
--- a/drivers/mcb/mcb-parse.c
+++ b/drivers/mcb/mcb-parse.c
@@ -26,19 +26,20 @@ static inline uint32_t get_next_dtype(void __iomem *p)
 }
 
 static int chameleon_parse_bdd(struct mcb_bus *bus,
-                        phys_addr_t mapbase,
+                        struct chameleon_bar *cb,
                         void __iomem *base)
 {
         return 0;
 }
 
 static int chameleon_parse_gdd(struct mcb_bus *bus,
-                        phys_addr_t mapbase,
-                        void __iomem *base)
+                        struct chameleon_bar *cb,
+                        void __iomem *base, int bar_count)
 {
         struct chameleon_gdd __iomem *gdd =
                 (struct chameleon_gdd __iomem *) base;
         struct mcb_device *mdev;
+        u32 dev_mapbase;
         u32 offset;
         u32 size;
         int ret;
@@ -61,13 +62,39 @@ static int chameleon_parse_gdd(struct mcb_bus *bus,
         mdev->group = GDD_GRP(reg2);
         mdev->inst = GDD_INS(reg2);
 
+        /*
+         * If the BAR is missing, dev_mapbase is zero, or if the
+         * device is IO mapped we just print a warning and go on with the
+         * next device, instead of completely stop the gdd parser
+         */
+        if (mdev->bar > bar_count - 1) {
+                pr_info("No BAR for 16z%03d\n", mdev->id);
+                ret = 0;
+                goto err;
+        }
+
+        dev_mapbase = cb[mdev->bar].addr;
+        if (!dev_mapbase) {
+                pr_info("BAR not assigned for 16z%03d\n", mdev->id);
+                ret = 0;
+                goto err;
+        }
+
+        if (dev_mapbase & 0x01) {
+                pr_info("IO mapped Device (16z%03d) not yet supported\n",
+                        mdev->id);
+                ret = 0;
+                goto err;
+        }
+
         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.start = dev_mapbase + offset;
+
         mdev->mem.end = mdev->mem.start + size - 1;
         mdev->mem.flags = IORESOURCE_MEM;
 
@@ -85,13 +112,76 @@ err:
         return ret;
 }
 
+static void chameleon_parse_bar(void __iomem *base,
+                                struct chameleon_bar *cb, int bar_count)
+{
+        char __iomem *p = base;
+        int i;
+
+        /* skip reg1 */
+        p += sizeof(__le32);
+
+        for (i = 0; i < bar_count; i++) {
+                cb[i].addr = readl(p);
+                cb[i].size = readl(p + 4);
+
+                p += sizeof(struct chameleon_bar);
+        }
+}
+
+static int chameleon_get_bar(char __iomem **base, phys_addr_t mapbase,
+                             struct chameleon_bar **cb)
+{
+        struct chameleon_bar *c;
+        int bar_count;
+        __le32 reg;
+        u32 dtype;
+
+        /*
+         * For those devices which are not connected
+         * to the PCI Bus (e.g. LPC) there is a bar
+         * descriptor located directly after the
+         * chameleon header. This header is comparable
+         * to a PCI header.
+         */
+        dtype = get_next_dtype(*base);
+        if (dtype == CHAMELEON_DTYPE_BAR) {
+                reg = readl(*base);
+
+                bar_count = BAR_CNT(reg);
+                if (bar_count <= 0 && bar_count > CHAMELEON_BAR_MAX)
+                        return -ENODEV;
+
+                c = kcalloc(bar_count, sizeof(struct chameleon_bar),
+                            GFP_KERNEL);
+                if (!c)
+                        return -ENOMEM;
+
+                chameleon_parse_bar(*base, c, bar_count);
+                *base += BAR_DESC_SIZE(bar_count);
+        } else {
+                c = kzalloc(sizeof(struct chameleon_bar), GFP_KERNEL);
+                if (!c)
+                        return -ENOMEM;
+
+                bar_count = 1;
+                c->addr = mapbase;
+        }
+
+        *cb = c;
+
+        return bar_count;
+}
+
 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;
+        struct chameleon_bar *cb;
+        char __iomem *p = base;
         int num_cells = 0;
+        uint32_t dtype;
+        int bar_count;
         int ret = 0;
         u32 hsize;
 
@@ -108,8 +198,8 @@ int chameleon_parse_cells(struct mcb_bus *bus, phys_addr_t mapbase,
         if (header->magic != CHAMELEONV2_MAGIC) {
                 pr_err("Unsupported chameleon version 0x%x\n",
                                 header->magic);
-                kfree(header);
-                return -ENODEV;
+                ret = -ENODEV;
+                goto free_header;
         }
         p += hsize;
 
@@ -119,16 +209,20 @@ int chameleon_parse_cells(struct mcb_bus *bus, phys_addr_t mapbase,
         snprintf(bus->name, CHAMELEON_FILENAME_LEN + 1, "%s",
                  header->filename);
 
+        bar_count = chameleon_get_bar(&p, mapbase, &cb);
+        if (bar_count < 0)
+                goto free_header;
+
         for_each_chameleon_cell(dtype, p) {
                 switch (dtype) {
                 case CHAMELEON_DTYPE_GENERAL: