powerpc/44x: Support OCM(On Chip Memory) for APM821xx SoC and Bluestone board

This patch consists of:
- Add driver for OCM component
- Export OCM Information at /sys/kernel/debug/ppc4xx_ocm/info

Signed-off-by: Vinh Nguyen Huu Tuong <vhtnguyen@apm.com>
Acked-by: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 416 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index a57600b3a4e3..f44f09f3d527 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_PPC_INDIRECT_PCI)	+= indirect_pci.o
 obj-$(CONFIG_PPC_I8259)         += i8259.o
 obj-$(CONFIG_IPIC)              += ipic.o
 obj-$(CONFIG_4xx)               += uic.o
+obj-$(CONFIG_PPC4xx_OCM)        += ppc4xx_ocm.o
 obj-$(CONFIG_4xx_SOC)           += ppc4xx_soc.o
 obj-$(CONFIG_XILINX_VIRTEX)     += xilinx_intc.o
 obj-$(CONFIG_XILINX_PCI)        += xilinx_pci.o
diff --git a/arch/powerpc/sysdev/ppc4xx_ocm.c b/arch/powerpc/sysdev/ppc4xx_ocm.c
new file mode 100644
index 000000000000..1b15f93479c3
--- /dev/null
+++ b/arch/powerpc/sysdev/ppc4xx_ocm.c
@@ -0,0 +1,415 @@
+/*
+ * PowerPC 4xx OCM memory allocation support
+ *
+ * (C) Copyright 2009, Applied Micro Circuits Corporation
+ * Victor Gallardo (vgallardo@amcc.com)
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/dma-mapping.h>
+#include <linux/of.h>
+#include <asm/rheap.h>
+#include <asm/ppc4xx_ocm.h>
+#include <linux/slab.h>
+#include <linux/debugfs.h>
+
+#define OCM_DISABLED    0
+#define OCM_ENABLED             1
+
+struct ocm_block {
+        struct list_head        list;
+        void __iomem            *addr;
+        int                                     size;
+        const char                      *owner;
+};
+
+/* non-cached or cached region */
+struct ocm_region {
+        phys_addr_t                     phys;
+        void __iomem            *virt;
+
+        int                                     memtotal;
+        int                                     memfree;
+
+        rh_info_t                       *rh;
+        struct list_head        list;
+};
+
+struct ocm_info {
+        int                                     index;
+        int                                     status;
+        int                                     ready;
+
+        phys_addr_t                     phys;
+
+        int                                     alignment;
+        int                                     memtotal;
+        int                                     cache_size;
+
+        struct ocm_region       nc;     /* non-cached region */
+        struct ocm_region       c;      /* cached region */
+};
+
+static struct ocm_info *ocm_nodes;
+static int ocm_count;
+
+static struct ocm_info *ocm_get_node(unsigned int index)
+{
+        if (index >= ocm_count) {
+                printk(KERN_ERR "PPC4XX OCM: invalid index");
+                return NULL;
+        }
+
+        return &ocm_nodes[index];
+}
+
+static int ocm_free_region(struct ocm_region *ocm_reg, const void *addr)
+{
+        struct ocm_block *blk, *tmp;
+        unsigned long offset;
+
+        if (!ocm_reg->virt)
+                return 0;
+
+        list_for_each_entry_safe(blk, tmp, &ocm_reg->list, list) {
+                if (blk->addr == addr) {
+                        offset = addr - ocm_reg->virt;
+                        ocm_reg->memfree += blk->size;
+                        rh_free(ocm_reg->rh, offset);
+                        list_del(&blk->list);
+                        kfree(blk);
+                        return 1;
+                }
+        }
+
+        return 0;
+}
+
+static void __init ocm_init_node(int count, struct device_node *node)
+{
+        struct ocm_info *ocm;
+
+        const unsigned int *cell_index;
+        const unsigned int *cache_size;
+        int len;
+
+        struct resource rsrc;
+        int ioflags;
+
+        ocm = ocm_get_node(count);
+
+        cell_index = of_get_property(node, "cell-index", &len);
+        if (!cell_index) {
+                printk(KERN_ERR "PPC4XX OCM: missing cell-index property");
+                return;
+        }
+        ocm->index = *cell_index;
+
+        if (of_device_is_available(node))
+                ocm->status = OCM_ENABLED;
+
+        cache_size = of_get_property(node, "cached-region-size", &len);
+        if (cache_size)
+                ocm->cache_size = *cache_size;
+
+        if (of_address_to_resource(node, 0, &rsrc)) {
+                printk(KERN_ERR "PPC4XX OCM%d: could not get resource address\n",
+                        ocm->index);
+                return;
+        }
+
+        ocm->phys = rsrc.start;
+        ocm->memtotal = (rsrc.end - rsrc.start + 1);
+
+        printk(KERN_INFO "PPC4XX OCM%d: %d Bytes (%s)\n",
+                ocm->index, ocm->memtotal,
+                (ocm->status == OCM_DISABLED) ? "disabled" : "enabled");
+
+        if (ocm->status == OCM_DISABLED)
+                return;
+
+        /* request region */
+
+        if (!request_mem_region(ocm->phys, ocm->memtotal, "ppc4xx_ocm")) {
+                printk(KERN_ERR "PPC4XX OCM%d: could not request region\n",
+                        ocm->index);
+                return;
+        }
+
+        /* Configure non-cached and cached regions */
+
+        ocm->nc.phys = ocm->phys;
+        ocm->nc.memtotal = ocm->memtotal - ocm->cache_size;
+        ocm->nc.memfree = ocm->nc.memtotal;
+
+        ocm->c.phys = ocm->phys + ocm->nc.memtotal;
+        ocm->c.memtotal = ocm->cache_size;
+        ocm->c.memfree = ocm->c.memtotal;
+
+        if (ocm->nc.memtotal == 0)
+                ocm->nc.phys = 0;
+
+        if (ocm->c.memtotal == 0)
+                ocm->c.phys = 0;
+
+        printk(KERN_INFO "PPC4XX OCM%d: %d Bytes (non-cached)\n",
+                ocm->index, ocm->nc.memtotal);
+
+        printk(KERN_INFO "PPC4XX OCM%d: %d Bytes (cached)\n",
+                ocm->index, ocm->c.memtotal);
+
+        /* ioremap the non-cached region */
+        if (ocm->nc.memtotal) {
+                ioflags = _PAGE_NO_CACHE | _PAGE_GUARDED | _PAGE_EXEC;
+                ocm->nc.virt = __ioremap(ocm->nc.phys, ocm->nc.memtotal,
+                                          ioflags);
+
+                if (!ocm->nc.virt) {
+                        printk(KERN_ERR
+                               "PPC4XX OCM%d: failed to ioremap non-cached memory\n",
+                               ocm->index);
+                        ocm->nc.memfree = 0;
+                        return;
+                }
+        }
+
+        /* ioremap the cached region */
+
+        if (ocm->c.memtotal) {
+                ioflags = _PAGE_EXEC;
+                ocm->c.virt = __ioremap(ocm->c.phys, ocm->c.memtotal,
+                                         ioflags);
+
+                if (!ocm->c.virt) {
+                        printk(KERN_ERR
+                               "PPC4XX OCM%d: failed to ioremap cached memory\n",
+                               ocm->index);
+                        ocm->c.memfree = 0;
+                        return;
+                }
+        }
+
+        /* Create Remote Heaps */
+
+        ocm->alignment = 4; /* default 4 byte alignment */
+
+        if (ocm->nc.virt) {
+                ocm->nc.rh = rh_create(ocm->alignment);
+                rh_attach_region(ocm->nc.rh, 0, ocm->nc.memtotal);
+        }
+
+        if (ocm->c.virt) {
+                ocm->c.rh = rh_create(ocm->alignment);
+                rh_attach_region(ocm->c.rh, 0, ocm->c.memtotal);
+        }
+
+        INIT_LIST_HEAD(&ocm->nc.list);
+        INIT_LIST_HEAD(&ocm->c.list);
+
+        ocm->ready = 1;
+
+        return;
+}
+
+static int ocm_debugfs_show(struct seq_file *m, void *v)
+{
+        struct ocm_block *blk, *tmp;
+        unsigned int i;
+
+        for (i = 0; i < ocm_count; i++) {
+                struct ocm_info *ocm = ocm_get_node(i);
+
+                if (!ocm || !ocm->ready)
+                        continue;
+
+                seq_printf(m, "PPC4XX OCM   : %d\n", ocm->index);
+                seq_printf(m, "PhysAddr     : 0x%llx\n", ocm->phys);
+                seq_printf(m, "MemTotal     : %d Bytes\n", ocm->memtotal);
+                seq_printf(m, "MemTotal(NC) : %d Bytes\n", ocm->nc.memtotal);
+                seq_printf(m, "MemTotal(C)  : %d Bytes\n", ocm->c.memtotal);
+
+                seq_printf(m, "\n");
+
+                seq_printf(m, "NC.PhysAddr  : 0x%llx\n", ocm->nc.phys);
+                seq_printf(m, "NC.VirtAddr  : 0x%p\n", ocm->nc.virt);
+                seq_printf(m, "NC.MemTotal  : %d Bytes\n", ocm->nc.memtotal);
+                seq_printf(m, "NC.MemFree   : %d Bytes\n", ocm->nc.memfree);
+
+                list_for_each_entry_safe(blk, tmp, &ocm->nc.list, list) {
+                        seq_printf(m, "NC.MemUsed   : %d Bytes (%s)\n",
+                                                        blk->size, blk->owner);
+                }
+
+                seq_printf(m, "\n");
+
+                seq_printf(m, "C.PhysAddr   : 0x%llx\n", ocm->c.phys);
+                seq_printf(m, "C.VirtAddr   : 0x%p\n", ocm->c.virt);
+                seq_printf(m, "C.MemTotal   : %d Bytes\n", ocm->c.memtotal);
+                seq_printf(m, "C.MemFree    : %d Bytes\n", ocm->c.memfree);
+
+                list_for_each_entry_safe(blk, tmp, &ocm->c.list, list) {
+                        seq_printf(m, "C.MemUsed    : %d Bytes (%s)\n",
+                                                blk->size, blk->owner);
+                }
+
+                seq_printf(m, "\n");
+        }
+
+        return 0;
+}
+
+static int ocm_debugfs_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, ocm_debugfs_show, NULL);
+}
+
+static const struct file_operations ocm_debugfs_fops = {
+        .open = ocm_debugfs_open,
+        .read = seq_read,
+        .llseek = seq_lseek,
+        .release = single_release,
+};
+
+static int ocm_debugfs_init(void)
+{
+        struct dentry *junk;
+
+        junk = debugfs_create_dir("ppc4xx_ocm", 0);
+        if (!junk) {
+                printk(KERN_ALERT "debugfs ppc4xx ocm: failed to create dir\n");
+                return -1;
+        }
+
+        if (debugfs_create_file("info", 0644, junk, NULL, &ocm_debugfs_fops)) {
+                printk(KERN_ALERT "debugfs ppc4xx ocm: failed to create file\n");
+                return -1;
+        }
+
+        return 0;
+}
+
+void *ppc4xx_ocm_alloc(phys_addr_t *phys, int size, int align,
+                        int flags, const char *owner)
+{
+        void __iomem *addr = NULL;
+        unsigned long offset;
+        struct ocm_info *ocm;
+        struct ocm_region *ocm_reg;
+        struct ocm_block *ocm_blk;
+        int i;
+
+        for (i = 0; i < ocm_count; i++) {
+                ocm = ocm_get_node(i);
+
+                if (!ocm || !ocm->ready)
+                        continue;
+
+                if (flags == PPC4XX_OCM_NON_CACHED)
+                        ocm_reg = &ocm->nc;
+                else
+                        ocm_reg = &ocm->c;
+
+                if (!ocm_reg->virt)
+                        continue;
+
+                if (align < ocm->alignment)
+                        align = ocm->alignment;
+
+                offset = rh_alloc_align(ocm_reg->rh, size, align, NULL);
+
+                if (IS_ERR_VALUE(offset))
+                        continue;
+
+                ocm_blk = kzalloc(sizeof(struct ocm_block *), GFP_KERNEL);
+                if (!ocm_blk) {
+                        printk(KERN_ERR "PPC4XX OCM: could not allocate ocm block");
+                        rh_free(ocm_reg->rh, offset);
+                        break;
+                }
+
+                *phys = ocm_reg->phys + offset;
+                addr = ocm_reg->virt + offset;
+                size = ALIGN(size, align);
+
+                ocm_blk->addr = addr;
+                ocm_blk->size = size;
+                ocm_blk->owner = owner;
+                list_add_tail(&ocm_blk->list, &ocm_reg->list);
+
+                ocm_reg->memfree -= size;
+
+                break;
+        }
+
+        return addr;
+}
+
+void ppc4xx_ocm_free(const void *addr)
+{
+        int i;
+
+        if (!addr)
+                return;
+
+        for (i = 0; i < ocm_count; i++) {
+                struct ocm_info *ocm = ocm_get_node(i);
+
+                if (!ocm || !ocm->ready)
+                        continue;
+
+                if (ocm_free_region(&ocm->nc, addr) ||
+                        ocm_free_region(&ocm->c, addr))
+                        return;
+        }
+}
+
+static int __init ppc4xx_ocm_init(void)
+{
+        struct device_node *np;
+        int count;
+
+        count = 0;
+        for_each_compatible_node(np, NULL, "ibm,ocm")
+                count++;
+
+        if (!count)
+                return 0;
+
+        ocm_nodes = kzalloc((count * sizeof(struct ocm_info)), GFP_KERNEL);
+        if (!ocm_nodes) {
+                printk(KERN_ERR "PPC4XX OCM: failed to allocate OCM nodes!\n");
+                return -ENOMEM;
+        }
+
+        ocm_count = count;
+        count = 0;
+
+        for_each_compatible_node(np, NULL, "ibm,ocm") {
+                ocm_init_node(count, np);
+                count++;
+        }
+
+        ocm_debugfs_init();
+
+        return 0;
+}
+
+arch_initcall(ppc4xx_ocm_init);