xref: /openbmc/linux/arch/arm/mach-omap1/mtd-xip.h (revision 89aba575)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * MTD primitives for XIP support. Architecture specific functions.
4  *
5  * Do not include this file directly. It's included from linux/mtd/xip.h
6  *
7  * Author: Vladimir Barinov <vbarinov@embeddedalley.com>
8  *
9  * (c) 2005 MontaVista Software, Inc.
10  */
11 
12 #ifndef __ARCH_OMAP_MTD_XIP_H__
13 #define __ARCH_OMAP_MTD_XIP_H__
14 
15 #include "hardware.h"
16 #include <linux/soc/ti/omap1-io.h>
17 #define OMAP_MPU_TIMER_BASE	(0xfffec500)
18 #define OMAP_MPU_TIMER_OFFSET	0x100
19 
20 typedef struct {
21 	u32 cntl;			/* CNTL_TIMER, R/W */
22 	u32 load_tim;			/* LOAD_TIM,   W */
23 	u32 read_tim;			/* READ_TIM,   R */
24 } xip_omap_mpu_timer_regs_t;
25 
26 #define xip_omap_mpu_timer_base(n)					\
27 ((volatile xip_omap_mpu_timer_regs_t*)OMAP1_IO_ADDRESS(OMAP_MPU_TIMER_BASE +	\
28 	(n)*OMAP_MPU_TIMER_OFFSET))
29 
30 static inline unsigned long xip_omap_mpu_timer_read(int nr)
31 {
32 	volatile xip_omap_mpu_timer_regs_t* timer = xip_omap_mpu_timer_base(nr);
33 	return timer->read_tim;
34 }
35 
36 #define xip_irqpending()	\
37 	(omap_readl(OMAP_IH1_ITR) & ~omap_readl(OMAP_IH1_MIR))
38 #define xip_currtime()		(~xip_omap_mpu_timer_read(0))
39 
40 /*
41  * It's permitted to do approximation for xip_elapsed_since macro
42  * (see linux/mtd/xip.h)
43  */
44 
45 #ifdef CONFIG_MACH_OMAP_PERSEUS2
46 #define xip_elapsed_since(x)	(signed)((~xip_omap_mpu_timer_read(0) - (x)) / 7)
47 #else
48 #define xip_elapsed_since(x)	(signed)((~xip_omap_mpu_timer_read(0) - (x)) / 6)
49 #endif
50 
51 /*
52  * xip_cpu_idle() is used when waiting for a delay equal or larger than
53  * the system timer tick period.  This should put the CPU into idle mode
54  * to save power and to be woken up only when some interrupts are pending.
55  * As above, this should not rely upon standard kernel code.
56  */
57 
58 #define xip_cpu_idle()  asm volatile ("mcr p15, 0, %0, c7, c0, 4" :: "r" (1))
59 
60 #endif /* __ARCH_OMAP_MTD_XIP_H__ */
61