MIPS: APRP: Add VPE loader support for CMP platforms.

This patch adds VPE loader support for platforms having a CMP.

Signed-off-by: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Reviewed-by: Qais Yousef <Qais.Yousef@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6092/

3 files changed, 186 insertions, 0 deletions

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 741fc31463c1..6395436c0569 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1907,6 +1907,11 @@ config MIPS_VPE_LOADER
           Includes a loader for loading an elf relocatable object
           onto another VPE and running it.
 
+config MIPS_VPE_LOADER_CMP
+        bool
+        default "y"
+        depends on MIPS_VPE_LOADER && MIPS_CMP
+
 config MIPS_VPE_LOADER_MT
         bool
         default "y"
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index de28da1a8757..e5a73568aa56 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_MIPS_CMP)		+= smp-cmp.o
 obj-$(CONFIG_CPU_MIPSR2)        += spram.o
 
 obj-$(CONFIG_MIPS_VPE_LOADER)   += vpe.o
+obj-$(CONFIG_MIPS_VPE_LOADER_CMP) += vpe-cmp.o
 obj-$(CONFIG_MIPS_VPE_LOADER_MT) += vpe-mt.o
 obj-$(CONFIG_MIPS_VPE_APSP_API) += rtlx.o
 
diff --git a/arch/mips/kernel/vpe-cmp.c b/arch/mips/kernel/vpe-cmp.c
new file mode 100644
index 000000000000..9268ebc0f61e
--- /dev/null
+++ b/arch/mips/kernel/vpe-cmp.c
@@ -0,0 +1,180 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2004, 2005 MIPS Technologies, Inc.  All rights reserved.
+ * Copyright (C) 2013 Imagination Technologies Ltd.
+ */
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include <asm/vpe.h>
+
+static int major;
+
+void cleanup_tc(struct tc *tc)
+{
+
+}
+
+static ssize_t store_kill(struct device *dev, struct device_attribute *attr,
+                          const char *buf, size_t len)
+{
+        struct vpe *vpe = get_vpe(aprp_cpu_index());
+        struct vpe_notifications *notifier;
+
+        list_for_each_entry(notifier, &vpe->notify, list)
+                notifier->stop(aprp_cpu_index());
+
+        release_progmem(vpe->load_addr);
+        vpe->state = VPE_STATE_UNUSED;
+
+        return len;
+}
+static DEVICE_ATTR(kill, S_IWUSR, NULL, store_kill);
+
+static ssize_t ntcs_show(struct device *cd, struct device_attribute *attr,
+                         char *buf)
+{
+        struct vpe *vpe = get_vpe(aprp_cpu_index());
+
+        return sprintf(buf, "%d\n", vpe->ntcs);
+}
+
+static ssize_t ntcs_store(struct device *dev, struct device_attribute *attr,
+                          const char *buf, size_t len)
+{
+        struct vpe *vpe = get_vpe(aprp_cpu_index());
+        unsigned long new;
+        int ret;
+
+        ret = kstrtoul(buf, 0, &new);
+        if (ret < 0)
+                return ret;
+
+        /* APRP can only reserve one TC in a VPE and no more. */
+        if (new != 1)
+                return -EINVAL;
+
+        vpe->ntcs = new;
+
+        return len;
+}
+static DEVICE_ATTR_RW(ntcs);
+
+static struct attribute *vpe_attrs[] = {
+        &dev_attr_kill.attr,
+        &dev_attr_ntcs.attr,
+        NULL,
+};
+ATTRIBUTE_GROUPS(vpe);
+
+static void vpe_device_release(struct device *cd)
+{
+        kfree(cd);
+}
+
+static struct class vpe_class = {
+        .name = "vpe",
+        .owner = THIS_MODULE,
+        .dev_release = vpe_device_release,
+        .dev_groups = vpe_groups,
+};
+
+static struct device vpe_device;
+
+int __init vpe_module_init(void)
+{
+        struct vpe *v = NULL;
+        struct tc *t;
+        int err;
+
+        if (!cpu_has_mipsmt) {
+                pr_warn("VPE loader: not a MIPS MT capable processor\n");
+                return -ENODEV;
+        }
+
+        if (num_possible_cpus() - aprp_cpu_index() < 1) {
+                pr_warn("No VPEs reserved for AP/SP, not initialize VPE loader\n"
+                        "Pass maxcpus=<n> argument as kernel argument\n");
+                return -ENODEV;
+        }
+
+        major = register_chrdev(0, VPE_MODULE_NAME, &vpe_fops);
+        if (major < 0) {
+                pr_warn("VPE loader: unable to register character device\n");
+                return major;
+        }
+
+        err = class_register(&vpe_class);
+        if (err) {
+                pr_err("vpe_class registration failed\n");
+                goto out_chrdev;
+        }
+
+        device_initialize(&vpe_device);
+        vpe_device.class        = &vpe_class,
+        vpe_device.parent       = NULL,
+        dev_set_name(&vpe_device, "vpe_sp");
+        vpe_device.devt = MKDEV(major, VPE_MODULE_MINOR);
+        err = device_add(&vpe_device);
+        if (err) {
+                pr_err("Adding vpe_device failed\n");
+                goto out_class;
+        }
+
+        t = alloc_tc(aprp_cpu_index());
+        if (!t) {
+                pr_warn("VPE: unable to allocate TC\n");
+                err = -ENOMEM;
+                goto out_dev;
+        }
+
+        /* VPE */
+        v = alloc_vpe(aprp_cpu_index());
+        if (v == NULL) {
+                pr_warn("VPE: unable to allocate VPE\n");
+                kfree(t);
+                err = -ENOMEM;
+                goto out_dev;
+        }
+
+        v->ntcs = 1;
+
+        /* add the tc to the list of this vpe's tc's. */
+        list_add(&t->tc, &v->tc);
+
+        /* TC */
+        t->pvpe = v;    /* set the parent vpe */
+
+        return 0;
+
+out_dev:
+        device_del(&vpe_device);
+
+out_class:
+        class_unregister(&vpe_class);
+
+out_chrdev:
+        unregister_chrdev(major, VPE_MODULE_NAME);
+
+        return err;
+}
+
+void __exit vpe_module_exit(void)
+{
+        struct vpe *v, *n;
+
+        device_del(&vpe_device);
+        class_unregister(&vpe_class);
+        unregister_chrdev(major, VPE_MODULE_NAME);
+
+        /* No locking needed here */
+        list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list)
+                if (v->state != VPE_STATE_UNUSED)
+                        release_vpe(v);
+}