Add read and write functions for accessing registers of I2C devices connected to the Aspeed I2C controller.
Signed-off-by: Stefan Berger <stef...@linux.ibm.com> Reviewed-by: Cédric Le Goater <c...@kaod.org> Reviewed-by: Ninad Palsule <ni...@linux.ibm.com> --- include/hw/i2c/aspeed_i2c.h | 7 +++ tests/qtest/qtest_aspeed.c | 109 ++++++++++++++++++++++++++++++++++++ tests/qtest/qtest_aspeed.h | 36 ++++++++++++ 3 files changed, 152 insertions(+) create mode 100644 tests/qtest/qtest_aspeed.c create mode 100644 tests/qtest/qtest_aspeed.h diff --git a/include/hw/i2c/aspeed_i2c.h b/include/hw/i2c/aspeed_i2c.h index adc904d6c1..51c944efea 100644 --- a/include/hw/i2c/aspeed_i2c.h +++ b/include/hw/i2c/aspeed_i2c.h @@ -38,6 +38,13 @@ OBJECT_DECLARE_TYPE(AspeedI2CState, AspeedI2CClass, ASPEED_I2C) #define ASPEED_I2C_OLD_NUM_REG 11 #define ASPEED_I2C_NEW_NUM_REG 22 +#define A_I2CD_M_STOP_CMD BIT(5) +#define A_I2CD_M_RX_CMD BIT(3) +#define A_I2CD_M_TX_CMD BIT(1) +#define A_I2CD_M_START_CMD BIT(0) + +#define A_I2CD_MASTER_EN BIT(0) + /* Tx State Machine */ #define I2CD_TX_STATE_MASK 0xf #define I2CD_IDLE 0x0 diff --git a/tests/qtest/qtest_aspeed.c b/tests/qtest/qtest_aspeed.c new file mode 100644 index 0000000000..2fcafc22fc --- /dev/null +++ b/tests/qtest/qtest_aspeed.c @@ -0,0 +1,109 @@ +/* + * Aspeed i2c bus interface for reading from and writing to i2c device registers + * + * Copyright (c) 2023 IBM Corporation + * + * Authors: + * Stefan Berger <stef...@linux.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" + +#include "qtest_aspeed.h" +#include "hw/i2c/aspeed_i2c.h" +#include "libqtest-single.h" + +static void aspeed_i2c_startup(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg) +{ + uint32_t v; + static int once; + + if (!once) { + /* one time: enable master */ + writel(baseaddr + A_I2CC_FUN_CTRL, 0); + v = readl(baseaddr + A_I2CC_FUN_CTRL) | A_I2CD_MASTER_EN; + writel(baseaddr + A_I2CC_FUN_CTRL, v); + once = 1; + } + + /* select device */ + writel(baseaddr + A_I2CD_BYTE_BUF, slave_addr << 1); + writel(baseaddr + A_I2CD_CMD, A_I2CD_M_START_CMD | A_I2CD_M_RX_CMD); + + /* select the register to write to */ + writel(baseaddr + A_I2CD_BYTE_BUF, reg); + writel(baseaddr + A_I2CD_CMD, A_I2CD_M_TX_CMD); +} + +static uint32_t aspeed_i2c_read_n(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, size_t nbytes) +{ + uint32_t res = 0; + uint32_t v; + size_t i; + + aspeed_i2c_startup(baseaddr, slave_addr, reg); + + for (i = 0; i < nbytes; i++) { + writel(baseaddr + A_I2CD_CMD, A_I2CD_M_RX_CMD); + v = readl(baseaddr + A_I2CD_BYTE_BUF) >> 8; + res |= (v & 0xff) << (i * 8); + } + + writel(baseaddr + A_I2CD_CMD, A_I2CD_M_STOP_CMD); + + return res; +} + +uint32_t aspeed_i2c_readl(uint32_t baseaddr, uint8_t slave_addr, uint8_t reg) +{ + return aspeed_i2c_read_n(baseaddr, slave_addr, reg, sizeof(uint32_t)); +} + +uint16_t aspeed_i2c_readw(uint32_t baseaddr, uint8_t slave_addr, uint8_t reg) +{ + return aspeed_i2c_read_n(baseaddr, slave_addr, reg, sizeof(uint16_t)); +} + +uint8_t aspeed_i2c_readb(uint32_t baseaddr, uint8_t slave_addr, uint8_t reg) +{ + return aspeed_i2c_read_n(baseaddr, slave_addr, reg, sizeof(uint8_t)); +} + +static void aspeed_i2c_write_n(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint32_t v, size_t nbytes) +{ + size_t i; + + aspeed_i2c_startup(baseaddr, slave_addr, reg); + + for (i = 0; i < nbytes; i++) { + writel(baseaddr + A_I2CD_BYTE_BUF, v & 0xff); + v >>= 8; + writel(baseaddr + A_I2CD_CMD, A_I2CD_M_TX_CMD); + } + + writel(baseaddr + A_I2CD_CMD, A_I2CD_M_STOP_CMD); +} + +void aspeed_i2c_writel(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint32_t v) +{ + aspeed_i2c_write_n(baseaddr, slave_addr, reg, v, sizeof(v)); +} + +void aspeed_i2c_writew(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint16_t v) +{ + aspeed_i2c_write_n(baseaddr, slave_addr, reg, v, sizeof(v)); +} + +void aspeed_i2c_writeb(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint8_t v) +{ + aspeed_i2c_write_n(baseaddr, slave_addr, reg, v, sizeof(v)); +} diff --git a/tests/qtest/qtest_aspeed.h b/tests/qtest/qtest_aspeed.h new file mode 100644 index 0000000000..a988c0a8a2 --- /dev/null +++ b/tests/qtest/qtest_aspeed.h @@ -0,0 +1,36 @@ +/* + * Aspeed i2c bus interface to reading and writing to i2c device registers + * + * Copyright (c) 2023 IBM Corporation + * + * Authors: + * Stefan Berger <stef...@linux.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ +#ifndef QTEST_ASPEED_H +#define QTEST_ASPEED_H + +#include <stdint.h> + +#define AST2600_ASPEED_I2C_BASE_ADDR 0x1e78a000 + +/* Implements only AST2600 I2C controller */ + +static inline uint32_t ast2600_i2c_calc_bus_addr(uint8_t bus_num) +{ + return AST2600_ASPEED_I2C_BASE_ADDR + 0x80 + bus_num * 0x80; +} + +uint8_t aspeed_i2c_readb(uint32_t baseaddr, uint8_t slave_addr, uint8_t reg); +uint16_t aspeed_i2c_readw(uint32_t baseaddr, uint8_t slave_addr, uint8_t reg); +uint32_t aspeed_i2c_readl(uint32_t baseaddr, uint8_t slave_addr, uint8_t reg); +void aspeed_i2c_writeb(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint8_t v); +void aspeed_i2c_writew(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint16_t v); +void aspeed_i2c_writel(uint32_t baseaddr, uint8_t slave_addr, + uint8_t reg, uint32_t v); + +#endif -- 2.39.2