ARC: irqflags - Interrupt enabling/disabling at in-core intc
ARC700 has an in-core intc which provides 2 priorities (a.k.a.) "levels"
of interrupts (per IRQ) hencforth referred to as L1/L2 interrupts.
CPU flags register STATUS32 has Interrupt Enable bits per level (E1/E2)
to globally enable (or disable) all IRQs at a level. Hence the
implementation of arch_local_irq_{save,restore,enable,disable}( )
The STATUS32 reg can be r/w only using the AUX Interface of ARC, hence
the use of LR/SR instructions. Further, E1/E2 bits in there can only be
updated using the FLAG insn.
The intc supports 32 interrupts - and per IRQ enabling is controlled by
a bit in the AUX_IENABLE register, hence the implmentation of
arch_{,un}mask_irq( ) routines.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/arc/include/asm/arcregs.h b/arch/arc/include/asm/arcregs.h
new file mode 100644
index 0000000..8ca8faf
--- /dev/null
+++ b/arch/arc/include/asm/arcregs.h
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _ASM_ARC_ARCREGS_H
+#define _ASM_ARC_ARCREGS_H
+
+#ifdef __KERNEL__
+
+/* status32 Bits Positions */
+#define STATUS_H_BIT 0 /* CPU Halted */
+#define STATUS_E1_BIT 1 /* Int 1 enable */
+#define STATUS_E2_BIT 2 /* Int 2 enable */
+#define STATUS_A1_BIT 3 /* Int 1 active */
+#define STATUS_A2_BIT 4 /* Int 2 active */
+#define STATUS_AE_BIT 5 /* Exception active */
+#define STATUS_DE_BIT 6 /* PC is in delay slot */
+#define STATUS_U_BIT 7 /* User/Kernel mode */
+#define STATUS_L_BIT 12 /* Loop inhibit */
+
+/* These masks correspond to the status word(STATUS_32) bits */
+#define STATUS_H_MASK (1<<STATUS_H_BIT)
+#define STATUS_E1_MASK (1<<STATUS_E1_BIT)
+#define STATUS_E2_MASK (1<<STATUS_E2_BIT)
+#define STATUS_A1_MASK (1<<STATUS_A1_BIT)
+#define STATUS_A2_MASK (1<<STATUS_A2_BIT)
+#define STATUS_AE_MASK (1<<STATUS_AE_BIT)
+#define STATUS_DE_MASK (1<<STATUS_DE_BIT)
+#define STATUS_U_MASK (1<<STATUS_U_BIT)
+#define STATUS_L_MASK (1<<STATUS_L_BIT)
+
+/* Auxiliary registers */
+#define AUX_IDENTITY 4
+#define AUX_INTR_VEC_BASE 0x25
+#define AUX_IRQ_LEV 0x200 /* IRQ Priority: L1 or L2 */
+#define AUX_IRQ_HINT 0x201 /* For generating Soft Interrupts */
+#define AUX_IRQ_LV12 0x43 /* interrupt level register */
+
+#define AUX_IENABLE 0x40c
+#define AUX_ITRIGGER 0x40d
+#define AUX_IPULSE 0x415
+
+#ifndef __ASSEMBLY__
+
+/*
+ ******************************************************************
+ * Inline ASM macros to read/write AUX Regs
+ * Essentially invocation of lr/sr insns from "C"
+ */
+
+#if 1
+
+#define read_aux_reg(reg) __builtin_arc_lr(reg)
+
+/* gcc builtin sr needs reg param to be long immediate */
+#define write_aux_reg(reg_immed, val) \
+ __builtin_arc_sr((unsigned int)val, reg_immed)
+
+#else
+
+#define read_aux_reg(reg) \
+({ \
+ unsigned int __ret; \
+ __asm__ __volatile__( \
+ " lr %0, [%1]" \
+ : "=r"(__ret) \
+ : "i"(reg)); \
+ __ret; \
+})
+
+/*
+ * Aux Reg address is specified as long immediate by caller
+ * e.g.
+ * write_aux_reg(0x69, some_val);
+ * This generates tightest code.
+ */
+#define write_aux_reg(reg_imm, val) \
+({ \
+ __asm__ __volatile__( \
+ " sr %0, [%1] \n" \
+ : \
+ : "ir"(val), "i"(reg_imm)); \
+})
+
+/*
+ * Aux Reg address is specified in a variable
+ * * e.g.
+ * reg_num = 0x69
+ * write_aux_reg2(reg_num, some_val);
+ * This has to generate glue code to load the reg num from
+ * memory to a reg hence not recommended.
+ */
+#define write_aux_reg2(reg_in_var, val) \
+({ \
+ unsigned int tmp; \
+ \
+ __asm__ __volatile__( \
+ " ld %0, [%2] \n\t" \
+ " sr %1, [%0] \n\t" \
+ : "=&r"(tmp) \
+ : "r"(val), "memory"(®_in_var)); \
+})
+
+#endif
+
+#endif /* __ASEMBLY__ */
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_ARC_ARCREGS_H */