1  /* SPDX-License-Identifier: GPL-2.0-or-later */
 2  
 3  /*
 4   * sdram_mode.h: Definitions for SDRAM Mode Register and Extended Mode Register
 5   */
 6  
 7  #ifndef __SDRAMMODE_H_DEFINED
 8  #define __SDRAMMODE_H_DEFINED
 9  
10  // SDRAM Mode Register definitions, per JESD79D
11  // These are transmitted via A0-A13
12  
13  // Burst length
14  #define SDRAM_BURST_2     (1<<0)
15  #define SDRAM_BURST_4     (2<<0)
16  #define SDRAM_BURST_8     (3<<0)
17  
18  #define SDRAM_BURST_SEQUENTIAL  (0<<3)
19  #define SDRAM_BURST_INTERLEAVED	(1<<3)
20  
21  #define SDRAM_CAS_2_0	  (2<<4)
22  #define SDRAM_CAS_3_0     (3<<4)	/* Optional for DDR 200-333 */
23  #define SDRAM_CAS_1_5     (5<<4)	/* Optional */
24  #define SDRAM_CAS_2_5     (6<<4)
25  #define SDRAM_CAS_MASK    (7<<4)
26  
27  #define SDRAM_MODE_NORMAL		(0 << 7)
28  #define SDRAM_MODE_TEST         (1 << 7)
29  #define SDRAM_MODE_DLL_RESET    (2 << 7)
30  
31  // Extended Mode Register
32  
33  #define SDRAM_EXTMODE_DLL_ENABLE	(0 << 0)
34  #define SDRAM_EXTMODE_DLL_DISABLE	(1 << 0)
35  
36  #define SDRAM_EXTMODE_DRIVE_NORMAL	(0 << 1)
37  #define SDRAM_EXTMODE_DRIVE_WEAK	(1 << 1)	/* Optional */
38  
39  #endif	// __SDRAMMODE_H_DEFINED