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| 1 | +#include "hardware/structs/ioqspi.h" |
| 2 | +#include "hardware/structs/qmi.h" |
| 3 | +#include "hardware/structs/xip_ctrl.h" |
| 4 | +#include "hardware/sync.h" |
| 5 | +#include "rp2_psram.h" |
| 6 | + |
| 7 | + |
| 8 | +void __no_inline_not_in_flash_func(psram_set_qmi_timing)() { |
| 9 | + // Make sure flash is deselected - QMI doesn't appear to have a busy flag(!) |
| 10 | + while ((ioqspi_hw->io[1].status & IO_QSPI_GPIO_QSPI_SS_STATUS_OUTTOPAD_BITS) != IO_QSPI_GPIO_QSPI_SS_STATUS_OUTTOPAD_BITS) { |
| 11 | + ; |
| 12 | + } |
| 13 | + |
| 14 | + // For > 133 MHz |
| 15 | + qmi_hw->m[0].timing = 0x40000202; |
| 16 | + |
| 17 | + // For <= 133 MHz |
| 18 | + // qmi_hw->m[0].timing = 0x40000101; |
| 19 | + |
| 20 | + // Force a read through XIP to ensure the timing is applied |
| 21 | + volatile uint32_t *ptr = (volatile uint32_t *)0x14000000; |
| 22 | + (void)*ptr; |
| 23 | +} |
| 24 | + |
| 25 | +size_t __no_inline_not_in_flash_func(psram_detect)() { |
| 26 | + int psram_size = 0; |
| 27 | + |
| 28 | + uint32_t intr_stash = save_and_disable_interrupts(); |
| 29 | + |
| 30 | + // Try and read the PSRAM ID via direct_csr. |
| 31 | + qmi_hw->direct_csr = 30 << QMI_DIRECT_CSR_CLKDIV_LSB | QMI_DIRECT_CSR_EN_BITS; |
| 32 | + |
| 33 | + // Need to poll for the cooldown on the last XIP transfer to expire |
| 34 | + // (via direct-mode BUSY flag) before it is safe to perform the first |
| 35 | + // direct-mode operation |
| 36 | + while ((qmi_hw->direct_csr & QMI_DIRECT_CSR_BUSY_BITS) != 0) { |
| 37 | + } |
| 38 | + |
| 39 | + // Exit out of QMI in case we've inited already |
| 40 | + qmi_hw->direct_csr |= QMI_DIRECT_CSR_ASSERT_CS1N_BITS; |
| 41 | + |
| 42 | + // Transmit as quad. |
| 43 | + qmi_hw->direct_tx = QMI_DIRECT_TX_OE_BITS | QMI_DIRECT_TX_IWIDTH_VALUE_Q << QMI_DIRECT_TX_IWIDTH_LSB | 0xf5; |
| 44 | + |
| 45 | + while ((qmi_hw->direct_csr & QMI_DIRECT_CSR_BUSY_BITS) != 0) { |
| 46 | + } |
| 47 | + |
| 48 | + (void)qmi_hw->direct_rx; |
| 49 | + |
| 50 | + qmi_hw->direct_csr &= ~(QMI_DIRECT_CSR_ASSERT_CS1N_BITS); |
| 51 | + |
| 52 | + // Read the id |
| 53 | + qmi_hw->direct_csr |= QMI_DIRECT_CSR_ASSERT_CS1N_BITS; |
| 54 | + uint8_t kgd = 0; |
| 55 | + uint8_t eid = 0; |
| 56 | + |
| 57 | + for (size_t i = 0; i < 7; i++) |
| 58 | + { |
| 59 | + if (i == 0) { |
| 60 | + qmi_hw->direct_tx = 0x9f; |
| 61 | + } else { |
| 62 | + qmi_hw->direct_tx = 0xff; |
| 63 | + } |
| 64 | + |
| 65 | + while ((qmi_hw->direct_csr & QMI_DIRECT_CSR_TXEMPTY_BITS) == 0) { |
| 66 | + } |
| 67 | + |
| 68 | + while ((qmi_hw->direct_csr & QMI_DIRECT_CSR_BUSY_BITS) != 0) { |
| 69 | + } |
| 70 | + |
| 71 | + if (i == 5) { |
| 72 | + kgd = qmi_hw->direct_rx; |
| 73 | + } else if (i == 6) { |
| 74 | + eid = qmi_hw->direct_rx; |
| 75 | + } else { |
| 76 | + (void)qmi_hw->direct_rx; |
| 77 | + } |
| 78 | + } |
| 79 | + |
| 80 | + // Disable direct csr. |
| 81 | + qmi_hw->direct_csr &= ~(QMI_DIRECT_CSR_ASSERT_CS1N_BITS | QMI_DIRECT_CSR_EN_BITS); |
| 82 | + |
| 83 | + if (kgd == 0x5D) { |
| 84 | + psram_size = 1024 * 1024; // 1 MiB |
| 85 | + uint8_t size_id = eid >> 5; |
| 86 | + if (eid == 0x26 || size_id == 2) { |
| 87 | + psram_size *= 8; // 8 MiB |
| 88 | + } else if (size_id == 0) { |
| 89 | + psram_size *= 2; // 2 MiB |
| 90 | + } else if (size_id == 1) { |
| 91 | + psram_size *= 4; // 4 MiB |
| 92 | + } |
| 93 | + } |
| 94 | + |
| 95 | + restore_interrupts(intr_stash); |
| 96 | + return psram_size; |
| 97 | +} |
| 98 | + |
| 99 | +size_t __no_inline_not_in_flash_func(psram_init)(uint cs_pin) { |
| 100 | + gpio_set_function(cs_pin, GPIO_FUNC_XIP_CS1); |
| 101 | + |
| 102 | + size_t psram_size = psram_detect(); |
| 103 | + |
| 104 | + if (!psram_size) { |
| 105 | + return 0; |
| 106 | + } |
| 107 | + |
| 108 | + psram_set_qmi_timing(); |
| 109 | + |
| 110 | + // Enable direct mode, PSRAM CS, clkdiv of 10. |
| 111 | + qmi_hw->direct_csr = 10 << QMI_DIRECT_CSR_CLKDIV_LSB | \ |
| 112 | + QMI_DIRECT_CSR_EN_BITS | \ |
| 113 | + QMI_DIRECT_CSR_AUTO_CS1N_BITS; |
| 114 | + while (qmi_hw->direct_csr & QMI_DIRECT_CSR_BUSY_BITS) { |
| 115 | + ; |
| 116 | + } |
| 117 | + |
| 118 | + // Enable QPI mode on the PSRAM |
| 119 | + const uint CMD_QPI_EN = 0x35; |
| 120 | + qmi_hw->direct_tx = QMI_DIRECT_TX_NOPUSH_BITS | CMD_QPI_EN; |
| 121 | + |
| 122 | + while (qmi_hw->direct_csr & QMI_DIRECT_CSR_BUSY_BITS) { |
| 123 | + ; |
| 124 | + } |
| 125 | + |
| 126 | + #if 0 |
| 127 | + // Set PSRAM timing for APS6404: |
| 128 | + // - Max select assumes a sys clock speed >= 240MHz |
| 129 | + // - Min deselect assumes a sys clock speed <= 305MHz |
| 130 | + // - Clkdiv of 2 is OK up to 266MHz. |
| 131 | + qmi_hw->m[1].timing = 1 << QMI_M1_TIMING_COOLDOWN_LSB | |
| 132 | + QMI_M1_TIMING_PAGEBREAK_VALUE_1024 << QMI_M1_TIMING_PAGEBREAK_LSB | |
| 133 | + 30 << QMI_M1_TIMING_MAX_SELECT_LSB | |
| 134 | + 5 << QMI_M1_TIMING_MIN_DESELECT_LSB | |
| 135 | + 3 << QMI_M1_TIMING_RXDELAY_LSB | |
| 136 | + 2 << QMI_M1_TIMING_CLKDIV_LSB; |
| 137 | + #else |
| 138 | + // Set PSRAM timing for APS6404: |
| 139 | + // - Max select assumes a sys clock speed >= 120MHz |
| 140 | + // - Min deselect assumes a sys clock speed <= 138MHz |
| 141 | + // - Clkdiv of 1 is OK up to 133MHz. |
| 142 | + qmi_hw->m[1].timing = 1 << QMI_M1_TIMING_COOLDOWN_LSB | |
| 143 | + QMI_M1_TIMING_PAGEBREAK_VALUE_1024 << QMI_M1_TIMING_PAGEBREAK_LSB | |
| 144 | + 15 << QMI_M1_TIMING_MAX_SELECT_LSB | |
| 145 | + 2 << QMI_M1_TIMING_MIN_DESELECT_LSB | |
| 146 | + 2 << QMI_M1_TIMING_RXDELAY_LSB | |
| 147 | + 1 << QMI_M1_TIMING_CLKDIV_LSB; |
| 148 | + #endif |
| 149 | + |
| 150 | + // Set PSRAM commands and formats |
| 151 | + qmi_hw->m[1].rfmt = |
| 152 | + QMI_M0_RFMT_PREFIX_WIDTH_VALUE_Q << QMI_M0_RFMT_PREFIX_WIDTH_LSB | \ |
| 153 | + QMI_M0_RFMT_ADDR_WIDTH_VALUE_Q << QMI_M0_RFMT_ADDR_WIDTH_LSB | \ |
| 154 | + QMI_M0_RFMT_SUFFIX_WIDTH_VALUE_Q << QMI_M0_RFMT_SUFFIX_WIDTH_LSB | \ |
| 155 | + QMI_M0_RFMT_DUMMY_WIDTH_VALUE_Q << QMI_M0_RFMT_DUMMY_WIDTH_LSB | \ |
| 156 | + QMI_M0_RFMT_DATA_WIDTH_VALUE_Q << QMI_M0_RFMT_DATA_WIDTH_LSB | \ |
| 157 | + QMI_M0_RFMT_PREFIX_LEN_VALUE_8 << QMI_M0_RFMT_PREFIX_LEN_LSB | \ |
| 158 | + 6 << QMI_M0_RFMT_DUMMY_LEN_LSB; |
| 159 | + |
| 160 | + qmi_hw->m[1].rcmd = 0xEB; |
| 161 | + |
| 162 | + qmi_hw->m[1].wfmt = |
| 163 | + QMI_M0_WFMT_PREFIX_WIDTH_VALUE_Q << QMI_M0_WFMT_PREFIX_WIDTH_LSB | \ |
| 164 | + QMI_M0_WFMT_ADDR_WIDTH_VALUE_Q << QMI_M0_WFMT_ADDR_WIDTH_LSB | \ |
| 165 | + QMI_M0_WFMT_SUFFIX_WIDTH_VALUE_Q << QMI_M0_WFMT_SUFFIX_WIDTH_LSB | \ |
| 166 | + QMI_M0_WFMT_DUMMY_WIDTH_VALUE_Q << QMI_M0_WFMT_DUMMY_WIDTH_LSB | \ |
| 167 | + QMI_M0_WFMT_DATA_WIDTH_VALUE_Q << QMI_M0_WFMT_DATA_WIDTH_LSB | \ |
| 168 | + QMI_M0_WFMT_PREFIX_LEN_VALUE_8 << QMI_M0_WFMT_PREFIX_LEN_LSB; |
| 169 | + |
| 170 | + qmi_hw->m[1].wcmd = 0x38; |
| 171 | + |
| 172 | + // Disable direct mode |
| 173 | + qmi_hw->direct_csr = 0; |
| 174 | + |
| 175 | + // Enable writes to PSRAM |
| 176 | + hw_set_bits(&xip_ctrl_hw->ctrl, XIP_CTRL_WRITABLE_M1_BITS); |
| 177 | + |
| 178 | + // TODO: Detect PSRAM ID and size |
| 179 | + return psram_size; |
| 180 | +} |
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