1 /*
2 * Copyright (c) 2015, Freescale Semiconductor, Inc.
3 * Copyright 2016-2020 NXP
4 * All rights reserved.
5 *
6 * SPDX-License-Identifier: BSD-3-Clause
7 */
8
9 #include "fsl_sdram.h"
10
11 /*******************************************************************************
12 * Definitions
13 ******************************************************************************/
14
15 /* Defines the sdram nop delay counts in initialize sequence. */
16 #define SDRAM_DELAY_COUNTS (125U)
17
18 /*******************************************************************************
19 * Prototypes
20 ******************************************************************************/
21
22 static status_t SDRAM_InitSequence(SDRAM_Type *base,
23 uint32_t address,
24 sdramc_block_selection_t whichBlock,
25 sdram_burst_len_t burstLen,
26 sdram_burst_type_t burstType,
27 sdram_cas_latency_t casLatency,
28 sdram_operation_mode_t opMode,
29 sdram_write_burst_mode_t writeBurstMode);
30
31 /*******************************************************************************
32 * Code
33 ******************************************************************************/
34
SDRAM_Init(SDRAM_Type * base,uint32_t address,uint32_t busClock_Hz)35 status_t SDRAM_Init(SDRAM_Type *base, uint32_t address, uint32_t busClock_Hz)
36 {
37 assert(address);
38
39 sdramc_config_t config;
40 sdramc_refresh_config_t refConfig;
41 sdramc_blockctl_config_t ctlConfig;
42
43 /* SDRAM refresh timing configuration. */
44 refConfig.refreshTime = kSDRAMC_RefreshThreeClocks;
45 /* Refresh time 4096 rows/ 64ms. */
46 refConfig.sdramRefreshRow = 15625;
47 refConfig.busClock_Hz = busClock_Hz;
48
49 /* SDRAM controller configuration. */
50 /* Port size: 16 bit, Command bit location: bit 20. */
51 ctlConfig.portSize = kSDRAMC_PortSize16Bit;
52 ctlConfig.location = kSDRAMC_Commandbit20;
53 ctlConfig.block = kSDRAMC_Block0;
54 /* SDRAM with trcd-15ns(min), trp-15ns(min), tras-37ns (min). */
55 ctlConfig.latency = kSDRAMC_LatencyOne;
56 ctlConfig.address = address;
57 ctlConfig.addressMask = 0xfc0000;
58
59 config.refreshConfig = &refConfig;
60 config.blockConfig = &ctlConfig;
61 config.numBlockConfig = 1;
62
63 /* SDRAM controller initialization. */
64 SDRAMC_Init(base, &config);
65
66 /* SDRAM initialization sequence. */
67 return SDRAM_InitSequence(base, address, kSDRAMC_Block0, kSDRAM_MrsBurstLenOne, kSDRAM_MrsSequential,
68 kSDRAM_MrsLatencyTwo, kSDRAM_MrsStandOperation, kSDRAM_MrsWriteBurst);
69 }
70
71 /*!
72 * @brief The SDRAM Initializes sequence.
73 *
74 */
SDRAM_InitSequence(SDRAM_Type * base,uint32_t address,sdramc_block_selection_t whichBlock,sdram_burst_len_t burstLen,sdram_burst_type_t burstType,sdram_cas_latency_t casLatency,sdram_operation_mode_t opMode,sdram_write_burst_mode_t writeBurstMode)75 static status_t SDRAM_InitSequence(SDRAM_Type *base,
76 uint32_t address,
77 sdramc_block_selection_t whichBlock,
78 sdram_burst_len_t burstLen,
79 sdram_burst_type_t burstType,
80 sdram_cas_latency_t casLatency,
81 sdram_operation_mode_t opMode,
82 sdram_write_burst_mode_t writeBurstMode)
83 {
84 uint32_t count = SDRAM_DELAY_COUNTS;
85 uint8_t *mrsAddr = NULL;
86 uint32_t addr = 0U;
87
88 /* Issue a PALL command. */
89 SDRAMC_SendCommand(base, whichBlock, kSDRAMC_PrechargeCommand);
90
91 /* Accessing a SDRAM location. */
92 *(uint8_t *)(address) = SDRAM_COMMAND_ACCESSVALUE;
93
94 /* Enable the refresh. */
95 SDRAMC_SendCommand(base, whichBlock, kSDRAMC_AutoRefreshEnableCommand);
96
97 /* Wait for at least 8 refresh cycles. */
98 while (count != 0U)
99 {
100 __NOP();
101 count--;
102 }
103
104 /* Issue MSR command. */
105 SDRAMC_SendCommand(base, whichBlock, kSDRAMC_ImrsCommand);
106
107 /* Put the right value on SDRAM address bus for SDRAM mode register,
108 * The address of SDRAM Pins is as below:
109 * A2 ~ A0: burst length 0
110 * 000->1
111 * 001->2
112 * 010->4
113 * 011->8
114 * res
115 * A3: burst type
116 * 0 -> seq
117 * 1 -> Interleave
118 *
119 * A6 ~ A4: CAS latency (should be set to equal to the tcasl in "sdram_latency_t")
120 * 000-> res
121 * 001-> 1
122 * 010-> 2
123 * 011-> 3
124 * res
125 * A8 ~ A7: Operationg Mode
126 * 00->Stardard Operation
127 * res
128 * A9: Write Burst Mode
129 * 0-> Programmed Burst Length
130 * 1-> Single Location Access
131 */
132 /* A2-A0. */
133 if (((uint8_t)burstLen & 0x1U) != 0x00U)
134 {
135 addr |= 1UL << SDRAM_A0;
136 }
137 if (((uint8_t)burstLen & 0x2U) != 0x00U)
138 {
139 addr |= 1UL << SDRAM_A1;
140 }
141 if (((uint8_t)burstLen & 0x4U) != 0x00U)
142 {
143 addr |= 1UL << SDRAM_A2;
144 }
145
146 /* Sdram address A3. */
147 if (((uint8_t)burstType & 0x1U) != 0x00U)
148 {
149 addr |= 1UL << SDRAM_A3;
150 }
151
152 /* Sdram address A6-A4. */
153 if (((uint8_t)casLatency & 0x1U) != 0x00U)
154 {
155 addr |= 1UL << SDRAM_A4;
156 }
157 if (((uint8_t)casLatency & 0x2U) != 0x00U)
158 {
159 addr |= 1UL << SDRAM_A5;
160 }
161 if (((uint8_t)casLatency & 0x4U) != 0x00U)
162 {
163 addr |= 1UL << SDRAM_A6;
164 }
165
166 /* Sdram address A8-A7. */
167 if (((uint8_t)opMode & 0x1U) != 0x00U)
168 {
169 addr |= 1UL << SDRAM_A7;
170 }
171 if (((uint8_t)opMode & 0x2U) != 0x00U)
172 {
173 addr |= 1UL << SDRAM_A8;
174 }
175
176 /* Sdram address A9. */
177 if (((uint8_t)writeBurstMode & 0x1U) != 0x00U)
178 {
179 addr |= 1UL << SDRAM_A9;
180 }
181 /* Set MRS register. */
182 mrsAddr = (uint8_t *)(address + addr);
183 /* Access sdram location. */
184 *mrsAddr = SDRAM_COMMAND_ACCESSVALUE;
185
186 return kStatus_Success;
187 }
188
