[POWERPC] bestcomm: core bestcomm support for Freescale MPC5200

This patch adds support for the core of the BestComm API
for the Freescale MPC5200(b). The BestComm engine is a
microcode-controlled / tasks-based DMA used by several
of the onchip devices.

Setting up the tasks / memory allocation and all common
low level functions are handled by this patch.
The specifics details of each tasks and their microcode
are split-out in separate patches.

This is not the official API, but a much cleaner one.
(hopefully)

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/arch/powerpc/sysdev/bestcomm/sram.c b/arch/powerpc/sysdev/bestcomm/sram.c
new file mode 100644
index 0000000..9978438
--- /dev/null
+++ b/arch/powerpc/sysdev/bestcomm/sram.c
@@ -0,0 +1,177 @@
+/*
+ * Simple memory allocator for on-board SRAM
+ *
+ *
+ * Maintainer : Sylvain Munaut <tnt@246tNt.com>
+ *
+ * Copyright (C) 2005 Sylvain Munaut <tnt@246tNt.com>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/of.h>
+
+#include <asm/io.h>
+#include <asm/mmu.h>
+
+#include "sram.h"
+
+
+/* Struct keeping our 'state' */
+struct bcom_sram *bcom_sram = NULL;
+EXPORT_SYMBOL_GPL(bcom_sram);	/* needed for inline functions */
+
+
+/* ======================================================================== */
+/* Public API                                                               */
+/* ======================================================================== */
+/* DO NOT USE in interrupts, if needed in irq handler, we should use the
+   _irqsave version of the spin_locks */
+
+int bcom_sram_init(struct device_node *sram_node, char *owner)
+{
+	int rv;
+	const u32 *regaddr_p;
+	u64 regaddr64, size64;
+	unsigned int psize;
+
+	/* Create our state struct */
+	if (bcom_sram) {
+		printk(KERN_ERR "%s: bcom_sram_init: "
+			"Already initialized !\n", owner);
+		return -EBUSY;
+	}
+
+	bcom_sram = kmalloc(sizeof(struct bcom_sram), GFP_KERNEL);
+	if (!bcom_sram) {
+		printk(KERN_ERR "%s: bcom_sram_init: "
+			"Couldn't allocate internal state !\n", owner);
+		return -ENOMEM;
+	}
+
+	/* Get address and size of the sram */
+	regaddr_p = of_get_address(sram_node, 0, &size64, NULL);
+	if (!regaddr_p) {
+		printk(KERN_ERR "%s: bcom_sram_init: "
+			"Invalid device node !\n", owner);
+		rv = -EINVAL;
+		goto error_free;
+	}
+
+	regaddr64 = of_translate_address(sram_node, regaddr_p);
+
+	bcom_sram->base_phys = (phys_addr_t) regaddr64;
+	bcom_sram->size = (unsigned int) size64;
+
+	/* Request region */
+	if (!request_mem_region(bcom_sram->base_phys, bcom_sram->size, owner)) {
+		printk(KERN_ERR "%s: bcom_sram_init: "
+			"Couldn't request region !\n", owner);
+		rv = -EBUSY;
+		goto error_free;
+	}
+
+	/* Map SRAM */
+		/* sram is not really __iomem */
+	bcom_sram->base_virt = (void*) ioremap(bcom_sram->base_phys, bcom_sram->size);
+
+	if (!bcom_sram->base_virt) {
+		printk(KERN_ERR "%s: bcom_sram_init: "
+			"Map error SRAM zone 0x%08lx (0x%0x)!\n",
+			owner, bcom_sram->base_phys, bcom_sram->size );
+		rv = -ENOMEM;
+		goto error_release;
+	}
+
+	/* Create an rheap (defaults to 32 bits word alignment) */
+	bcom_sram->rh = rh_create(4);
+
+	/* Attach the free zones */
+#if 0
+	/* Currently disabled ... for future use only */
+	reg_addr_p = of_get_property(sram_node, "available", &psize);
+#else
+	regaddr_p = NULL;
+	psize = 0;
+#endif
+
+	if (!regaddr_p || !psize) {
+		/* Attach the whole zone */
+		rh_attach_region(bcom_sram->rh, 0, bcom_sram->size);
+	} else {
+		/* Attach each zone independently */
+		while (psize >= 2 * sizeof(u32)) {
+			phys_addr_t zbase = of_translate_address(sram_node, regaddr_p);
+			rh_attach_region(bcom_sram->rh, zbase - bcom_sram->base_phys, regaddr_p[1]);
+			regaddr_p += 2;
+			psize -= 2 * sizeof(u32);
+		}
+	}
+
+	/* Init our spinlock */
+	spin_lock_init(&bcom_sram->lock);
+
+	return 0;
+
+error_release:
+	release_mem_region(bcom_sram->base_phys, bcom_sram->size);
+error_free:
+	kfree(bcom_sram);
+	bcom_sram = NULL;
+
+	return rv;
+}
+EXPORT_SYMBOL_GPL(bcom_sram_init);
+
+void bcom_sram_cleanup(void)
+{
+	/* Free resources */
+	if (bcom_sram) {
+		rh_destroy(bcom_sram->rh);
+		iounmap((void __iomem *)bcom_sram->base_virt);
+		release_mem_region(bcom_sram->base_phys, bcom_sram->size);
+		kfree(bcom_sram);
+		bcom_sram = NULL;
+	}
+}
+EXPORT_SYMBOL_GPL(bcom_sram_cleanup);
+
+void* bcom_sram_alloc(int size, int align, phys_addr_t *phys)
+{
+	unsigned long offset;
+
+	spin_lock(&bcom_sram->lock);
+	offset = rh_alloc_align(bcom_sram->rh, size, align, NULL);
+	spin_unlock(&bcom_sram->lock);
+
+	if (IS_ERR_VALUE(offset))
+		return NULL;
+
+	*phys = bcom_sram->base_phys + offset;
+	return bcom_sram->base_virt + offset;
+}
+EXPORT_SYMBOL_GPL(bcom_sram_alloc);
+
+void bcom_sram_free(void *ptr)
+{
+	unsigned long offset;
+
+	if (!ptr)
+		return;
+
+	offset = ptr - bcom_sram->base_virt;
+
+	spin_lock(&bcom_sram->lock);
+	rh_free(bcom_sram->rh, offset);
+	spin_unlock(&bcom_sram->lock);
+}
+EXPORT_SYMBOL_GPL(bcom_sram_free);
+