| 1 | /* |
| 2 | * BCM2835 SPI Master Controller |
| 3 | * |
| 4 | * Copyright (c) 2024 Rayhan Faizel <rayhan.faizel@gmail.com> |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | */ |
| 24 | |
| 25 | #include "hw/core/sysbus.h" |
| 26 | #include "hw/ssi/ssi.h" |
| 27 | #include "qom/object.h" |
| 28 | #include "qemu/fifo8.h" |
| 29 | |
| 30 | #define TYPE_BCM2835_SPI "bcm2835-spi" |
| 31 | OBJECT_DECLARE_SIMPLE_TYPE(BCM2835SPIState, BCM2835_SPI) |
| 32 | |
| 33 | /* |
| 34 | * Though BCM2835 documentation says FIFOs have a capacity of 16, |
| 35 | * FIFOs are actually 16 words in size or effectively 64 bytes when operating |
| 36 | * in non DMA mode. |
| 37 | */ |
| 38 | #define FIFO_SIZE 64 |
| 39 | #define FIFO_SIZE_3_4 48 |
| 40 | |
| 41 | #define RO_MASK 0x1f0000 |
| 42 | |
| 43 | #define BCM2835_SPI_CS 0x00 |
| 44 | #define BCM2835_SPI_FIFO 0x04 |
| 45 | #define BCM2835_SPI_CLK 0x08 |
| 46 | #define BCM2835_SPI_DLEN 0x0c |
| 47 | #define BCM2835_SPI_LTOH 0x10 |
| 48 | #define BCM2835_SPI_DC 0x14 |
| 49 | |
| 50 | #define BCM2835_SPI_CS_RXF BIT(20) |
| 51 | #define BCM2835_SPI_CS_RXR BIT(19) |
| 52 | #define BCM2835_SPI_CS_TXD BIT(18) |
| 53 | #define BCM2835_SPI_CS_RXD BIT(17) |
| 54 | #define BCM2835_SPI_CS_DONE BIT(16) |
| 55 | #define BCM2835_SPI_CS_LEN BIT(13) |
| 56 | #define BCM2835_SPI_CS_REN BIT(12) |
| 57 | #define BCM2835_SPI_CS_INTR BIT(10) |
| 58 | #define BCM2835_SPI_CS_INTD BIT(9) |
| 59 | #define BCM2835_SPI_CS_DMAEN BIT(8) |
| 60 | #define BCM2835_SPI_CS_TA BIT(7) |
| 61 | #define BCM2835_SPI_CLEAR_RX BIT(5) |
| 62 | #define BCM2835_SPI_CLEAR_TX BIT(4) |
| 63 | |
| 64 | struct BCM2835SPIState { |
| 65 | /* <private> */ |
| 66 | SysBusDevice parent_obj; |
| 67 | |
| 68 | /* <public> */ |
| 69 | SSIBus *bus; |
| 70 | MemoryRegion iomem; |
| 71 | qemu_irq irq; |
| 72 | |
| 73 | uint32_t cs; |
| 74 | uint32_t clk; |
| 75 | uint32_t dlen; |
| 76 | uint32_t ltoh; |
| 77 | uint32_t dc; |
| 78 | |
| 79 | Fifo8 tx_fifo; |
| 80 | Fifo8 rx_fifo; |
| 81 | }; |