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-rw-r--r--arch/mips/netlogic/xlp/cop2-ex.c118
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/mips/netlogic/xlp/cop2-ex.c b/arch/mips/netlogic/xlp/cop2-ex.c
new file mode 100644
index 000000000000..52bc5de42005
--- /dev/null
+++ b/arch/mips/netlogic/xlp/cop2-ex.c
@@ -0,0 +1,118 @@
+/*
+ * 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) 2013 Broadcom Corporation.
+ *
+ * based on arch/mips/cavium-octeon/cpu.c
+ * Copyright (C) 2009 Wind River Systems,
+ * written by Ralf Baechle <ralf@linux-mips.org>
+ */
+#include <linux/init.h>
+#include <linux/irqflags.h>
+#include <linux/notifier.h>
+#include <linux/prefetch.h>
+#include <linux/sched.h>
+
+#include <asm/cop2.h>
+#include <asm/current.h>
+#include <asm/mipsregs.h>
+#include <asm/page.h>
+
+#include <asm/netlogic/mips-extns.h>
+
+/*
+ * 64 bit ops are done in inline assembly to support 32 bit
+ * compilation
+ */
+void nlm_cop2_save(struct nlm_cop2_state *r)
+{
+ asm volatile(
+ ".set push\n"
+ ".set noat\n"
+ "dmfc2 $1, $0, 0\n"
+ "sd $1, 0(%1)\n"
+ "dmfc2 $1, $0, 1\n"
+ "sd $1, 8(%1)\n"
+ "dmfc2 $1, $0, 2\n"
+ "sd $1, 16(%1)\n"
+ "dmfc2 $1, $0, 3\n"
+ "sd $1, 24(%1)\n"
+ "dmfc2 $1, $1, 0\n"
+ "sd $1, 0(%2)\n"
+ "dmfc2 $1, $1, 1\n"
+ "sd $1, 8(%2)\n"
+ "dmfc2 $1, $1, 2\n"
+ "sd $1, 16(%2)\n"
+ "dmfc2 $1, $1, 3\n"
+ "sd $1, 24(%2)\n"
+ ".set pop\n"
+ : "=m"(*r)
+ : "r"(r->tx), "r"(r->rx));
+
+ r->tx_msg_status = __read_32bit_c2_register($2, 0);
+ r->rx_msg_status = __read_32bit_c2_register($3, 0) & 0x0fffffff;
+}
+
+void nlm_cop2_restore(struct nlm_cop2_state *r)
+{
+ u32 rstat;
+
+ asm volatile(
+ ".set push\n"
+ ".set noat\n"
+ "ld $1, 0(%1)\n"
+ "dmtc2 $1, $0, 0\n"
+ "ld $1, 8(%1)\n"
+ "dmtc2 $1, $0, 1\n"
+ "ld $1, 16(%1)\n"
+ "dmtc2 $1, $0, 2\n"
+ "ld $1, 24(%1)\n"
+ "dmtc2 $1, $0, 3\n"
+ "ld $1, 0(%2)\n"
+ "dmtc2 $1, $1, 0\n"
+ "ld $1, 8(%2)\n"
+ "dmtc2 $1, $1, 1\n"
+ "ld $1, 16(%2)\n"
+ "dmtc2 $1, $1, 2\n"
+ "ld $1, 24(%2)\n"
+ "dmtc2 $1, $1, 3\n"
+ ".set pop\n"
+ : : "m"(*r), "r"(r->tx), "r"(r->rx));
+
+ __write_32bit_c2_register($2, 0, r->tx_msg_status);
+ rstat = __read_32bit_c2_register($3, 0) & 0xf0000000u;
+ __write_32bit_c2_register($3, 0, r->rx_msg_status | rstat);
+}
+
+static int nlm_cu2_call(struct notifier_block *nfb, unsigned long action,
+ void *data)
+{
+ unsigned long flags;
+ unsigned int status;
+
+ switch (action) {
+ case CU2_EXCEPTION:
+ if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
+ break;
+ local_irq_save(flags);
+ KSTK_STATUS(current) |= ST0_CU2;
+ status = read_c0_status();
+ write_c0_status(status | ST0_CU2);
+ nlm_cop2_restore(&(current->thread.cp2));
+ write_c0_status(status & ~ST0_CU2);
+ local_irq_restore(flags);
+ pr_info("COP2 access enabled for pid %d (%s)\n",
+ current->pid, current->comm);
+ return NOTIFY_BAD; /* Don't call default notifier */
+ }
+
+ return NOTIFY_OK; /* Let default notifier send signals */
+}
+
+static int __init nlm_cu2_setup(void)
+{
+ return cu2_notifier(nlm_cu2_call, 0);
+}
+early_initcall(nlm_cu2_setup);