qemu/include/hw/ssi/bcm2835_spi.h
Rayhan Faizel 28004fb741 hw/ssi: Implement BCM2835 SPI Controller
This patch adds the SPI controller for the BCM2835. Polling and interrupt modes
of transfer are supported. DMA and LoSSI modes are currently unimplemented.

Signed-off-by: Rayhan Faizel <rayhan.faizel@gmail.com>
Message-id: 20240129221807.2983148-2-rayhan.faizel@gmail.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2024-02-02 13:51:59 +00:00

82 lines
2.6 KiB
C

/*
* BCM2835 SPI Master Controller
*
* Copyright (c) 2024 Rayhan Faizel <rayhan.faizel@gmail.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "hw/sysbus.h"
#include "hw/ssi/ssi.h"
#include "qom/object.h"
#include "qemu/fifo8.h"
#define TYPE_BCM2835_SPI "bcm2835-spi"
OBJECT_DECLARE_SIMPLE_TYPE(BCM2835SPIState, BCM2835_SPI)
/*
* Though BCM2835 documentation says FIFOs have a capacity of 16,
* FIFOs are actually 16 words in size or effectively 64 bytes when operating
* in non DMA mode.
*/
#define FIFO_SIZE 64
#define FIFO_SIZE_3_4 48
#define RO_MASK 0x1f0000
#define BCM2835_SPI_CS 0x00
#define BCM2835_SPI_FIFO 0x04
#define BCM2835_SPI_CLK 0x08
#define BCM2835_SPI_DLEN 0x0c
#define BCM2835_SPI_LTOH 0x10
#define BCM2835_SPI_DC 0x14
#define BCM2835_SPI_CS_RXF BIT(20)
#define BCM2835_SPI_CS_RXR BIT(19)
#define BCM2835_SPI_CS_TXD BIT(18)
#define BCM2835_SPI_CS_RXD BIT(17)
#define BCM2835_SPI_CS_DONE BIT(16)
#define BCM2835_SPI_CS_LEN BIT(13)
#define BCM2835_SPI_CS_REN BIT(12)
#define BCM2835_SPI_CS_INTR BIT(10)
#define BCM2835_SPI_CS_INTD BIT(9)
#define BCM2835_SPI_CS_DMAEN BIT(8)
#define BCM2835_SPI_CS_TA BIT(7)
#define BCM2835_SPI_CLEAR_RX BIT(5)
#define BCM2835_SPI_CLEAR_TX BIT(4)
struct BCM2835SPIState {
/* <private> */
SysBusDevice parent_obj;
/* <public> */
SSIBus *bus;
MemoryRegion iomem;
qemu_irq irq;
uint32_t cs;
uint32_t clk;
uint32_t dlen;
uint32_t ltoh;
uint32_t dc;
Fifo8 tx_fifo;
Fifo8 rx_fifo;
};