[net-next-2.6.git] / drivers / mtd / devices / ms02-nv.h

/*
 *	Copyright (c) 2001, 2003  Maciej W. Rozycki
 *
 *	DEC MS02-NV (54-20948-01) battery backed-up NVRAM module for
 *	DECstation/DECsystem 5000/2x0 and DECsystem 5900 and 5900/260
 *	systems.
 *
 *	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.
 */

#include <linux/ioport.h>
#include <linux/mtd/mtd.h>

/*
 * Addresses are decoded as follows:
 *
 * 0x000000 - 0x3fffff	SRAM
 * 0x400000 - 0x7fffff	CSR
 *
 * Within the SRAM area the following ranges are forced by the system
 * firmware:
 *
 * 0x000000 - 0x0003ff	diagnostic area, destroyed upon a reboot
 * 0x000400 - ENDofRAM	storage area, available to operating systems
 *
 * but we can't really use the available area right from 0x000400 as
 * the first word is used by the firmware as a status flag passed
 * from an operating system.  If anything but the valid data magic
 * ID value is found, the firmware considers the SRAM clean, i.e.
 * containing no valid data, and disables the battery resulting in
 * data being erased as soon as power is switched off.  So the choice
 * for the start address of the user-available is 0x001000 which is
 * nicely page aligned.  The area between 0x000404 and 0x000fff may
 * be used by the driver for own needs.
 *
 * The diagnostic area defines two status words to be read by an
 * operating system, a magic ID to distinguish a MS02-NV board from
 * anything else and a status information providing results of tests
 * as well as the size of SRAM available, which can be 1MiB or 2MiB
 * (that's what the firmware handles; no idea if 2MiB modules ever
 * existed).
 *
 * The firmware only handles the MS02-NV board if installed in the
 * last (15th) slot, so for any other location the status information
 * stored in the SRAM cannot be relied upon.  But from the hardware
 * point of view there is no problem using up to 14 such boards in a
 * system -- only the 1st slot needs to be filled with a DRAM module.
 * The MS02-NV board is ECC-protected, like other MS02 memory boards.
 *
 * The state of the battery as provided by the CSR is reflected on
 * the two onboard LEDs.  When facing the battery side of the board,
 * with the LEDs at the top left and the battery at the bottom right
 * (i.e. looking from the back side of the system box), their meaning
 * is as follows (the system has to be powered on):
 *
 * left LED		battery disable status: lit = enabled
 * right LED		battery condition status: lit = OK
 */

/* MS02-NV iomem register offsets. */
#define MS02NV_CSR		0x400000	/* control & status register */

/* MS02-NV CSR status bits. */
#define MS02NV_CSR_BATT_OK	0x01		/* battery OK */
#define MS02NV_CSR_BATT_OFF	0x02		/* battery disabled */


/* MS02-NV memory offsets. */
#define MS02NV_DIAG		0x0003f8	/* diagnostic status */
#define MS02NV_MAGIC		0x0003fc	/* MS02-NV magic ID */
#define MS02NV_VALID		0x000400	/* valid data magic ID */
#define MS02NV_RAM		0x001000	/* user-exposed RAM start */

/* MS02-NV diagnostic status bits. */
#define MS02NV_DIAG_TEST	0x01		/* SRAM test done (?) */
#define MS02NV_DIAG_RO		0x02		/* SRAM r/o test done */
#define MS02NV_DIAG_RW		0x04		/* SRAM r/w test done */
#define MS02NV_DIAG_FAIL	0x08		/* SRAM test failed */
#define MS02NV_DIAG_SIZE_MASK	0xf0		/* SRAM size mask */
#define MS02NV_DIAG_SIZE_SHIFT	0x10		/* SRAM size shift (left) */

/* MS02-NV general constants. */
#define MS02NV_ID		0x03021966	/* MS02-NV magic ID value */
#define MS02NV_VALID_ID		0xbd100248	/* valid data magic ID value */
#define MS02NV_SLOT_SIZE	0x800000	/* size of the address space
						   decoded by the module */


typedef volatile u32 ms02nv_uint;

struct ms02nv_private {
	struct mtd_info *next;
	struct {
		struct resource *module;
		struct resource *diag_ram;
		struct resource *user_ram;
		struct resource *csr;
	} resource;
	u_char *addr;
	size_t size;
	u_char *uaddr;
};
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (c) 2001, 2003 Maciej W. Rozycki
	3	*
	4	* DEC MS02-NV (54-20948-01) battery backed-up NVRAM module for
	5	* DECstation/DECsystem 5000/2x0 and DECsystem 5900 and 5900/260
	6	* systems.
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version
	11	* 2 of the License, or (at your option) any later version.
1da177e4 LT	12	*/
	13
	14	#include <linux/ioport.h>
	15	#include <linux/mtd/mtd.h>
	16
	17	/*
	18	* Addresses are decoded as follows:
	19	*
	20	* 0x000000 - 0x3fffff SRAM
	21	* 0x400000 - 0x7fffff CSR
	22	*
	23	* Within the SRAM area the following ranges are forced by the system
	24	* firmware:
	25	*
	26	* 0x000000 - 0x0003ff diagnostic area, destroyed upon a reboot
	27	* 0x000400 - ENDofRAM storage area, available to operating systems
	28	*
	29	* but we can't really use the available area right from 0x000400 as
	30	* the first word is used by the firmware as a status flag passed
	31	* from an operating system. If anything but the valid data magic
	32	* ID value is found, the firmware considers the SRAM clean, i.e.
	33	* containing no valid data, and disables the battery resulting in
	34	* data being erased as soon as power is switched off. So the choice
	35	* for the start address of the user-available is 0x001000 which is
	36	* nicely page aligned. The area between 0x000404 and 0x000fff may
	37	* be used by the driver for own needs.
	38	*
	39	* The diagnostic area defines two status words to be read by an
	40	* operating system, a magic ID to distinguish a MS02-NV board from
	41	* anything else and a status information providing results of tests
	42	* as well as the size of SRAM available, which can be 1MiB or 2MiB
	43	* (that's what the firmware handles; no idea if 2MiB modules ever
	44	* existed).
	45	*
	46	* The firmware only handles the MS02-NV board if installed in the
	47	* last (15th) slot, so for any other location the status information
	48	* stored in the SRAM cannot be relied upon. But from the hardware
	49	* point of view there is no problem using up to 14 such boards in a
	50	* system -- only the 1st slot needs to be filled with a DRAM module.
	51	* The MS02-NV board is ECC-protected, like other MS02 memory boards.
	52	*
	53	* The state of the battery as provided by the CSR is reflected on
	54	* the two onboard LEDs. When facing the battery side of the board,
	55	* with the LEDs at the top left and the battery at the bottom right
	56	* (i.e. looking from the back side of the system box), their meaning
	57	* is as follows (the system has to be powered on):
	58	*
	59	* left LED battery disable status: lit = enabled
	60	* right LED battery condition status: lit = OK
	61	*/
	62
	63	/* MS02-NV iomem register offsets. */
	64	#define MS02NV_CSR 0x400000 /* control & status register */
	65
	66	/* MS02-NV CSR status bits. */
	67	#define MS02NV_CSR_BATT_OK 0x01 /* battery OK */
	68	#define MS02NV_CSR_BATT_OFF 0x02 /* battery disabled */
	69
	70
	71	/* MS02-NV memory offsets. */
	72	#define MS02NV_DIAG 0x0003f8 /* diagnostic status */
	73	#define MS02NV_MAGIC 0x0003fc /* MS02-NV magic ID */
	74	#define MS02NV_VALID 0x000400 /* valid data magic ID */
	75	#define MS02NV_RAM 0x001000 /* user-exposed RAM start */
76
77	/* MS02-NV diagnostic status bits. */
78	#define MS02NV_DIAG_TEST 0x01 /* SRAM test done (?) */
79	#define MS02NV_DIAG_RO 0x02 /* SRAM r/o test done */
80	#define MS02NV_DIAG_RW 0x04 /* SRAM r/w test done */
81	#define MS02NV_DIAG_FAIL 0x08 /* SRAM test failed */
82	#define MS02NV_DIAG_SIZE_MASK 0xf0 /* SRAM size mask */
83	#define MS02NV_DIAG_SIZE_SHIFT 0x10 /* SRAM size shift (left) */
84
85	/* MS02-NV general constants. */
86	#define MS02NV_ID 0x03021966 /* MS02-NV magic ID value */
87	#define MS02NV_VALID_ID 0xbd100248 /* valid data magic ID value */
88	#define MS02NV_SLOT_SIZE 0x800000 /* size of the address space
89	decoded by the module */
90
91
92	typedef volatile u32 ms02nv_uint;
93
94	struct ms02nv_private {
95	struct mtd_info *next;
96	struct {
97	struct resource *module;
98	struct resource *diag_ram;
99	struct resource *user_ram;
100	struct resource *csr;
101	} resource;
102	u_char *addr;
103	size_t size;
104	u_char *uaddr;
105	};