[U-Boot] [RFC/RESEND 12/22] i2c: add thunderx I2C driver
Tim Harvey
tharvey at gateworks.com
Mon Mar 4 17:34:27 UTC 2019
Signed-off-by: Tim Harvey <tharvey at gateworks.com>
---
configs/thunderx_81xx_defconfig | 2 +
drivers/i2c/Kconfig | 7 +
drivers/i2c/Makefile | 1 +
drivers/i2c/thunderx_i2c.c | 878 ++++++++++++++++++++++++++++++++
include/configs/thunderx_81xx.h | 2 +
5 files changed, 890 insertions(+)
create mode 100644 drivers/i2c/thunderx_i2c.c
diff --git a/configs/thunderx_81xx_defconfig b/configs/thunderx_81xx_defconfig
index d07b0e5804..e43aa9750d 100644
--- a/configs/thunderx_81xx_defconfig
+++ b/configs/thunderx_81xx_defconfig
@@ -22,11 +22,13 @@ CONFIG_SYS_PROMPT="ThunderX_81XX> "
# CONFIG_CMD_ENV_EXISTS is not set
# CONFIG_CMD_FLASH is not set
CONFIG_CMD_GPIO=y
+CONFIG_CMD_I2C=y
CONFIG_CMD_PCI=y
# CONFIG_CMD_NET is not set
CONFIG_DEFAULT_DEVICE_TREE="thunderx-81xx"
CONFIG_DM=y
CONFIG_DM_GPIO=y
+CONFIG_DM_I2C=y
CONFIG_LED=y
CONFIG_LED_GPIO=y
# CONFIG_MMC is not set
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index 1ef22e6bcd..0424b54eb4 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -374,6 +374,13 @@ config SYS_I2C_SANDBOX
bus. Devices can be attached to the bus using the device tree
which specifies the driver to use. See sandbox.dts as an example.
+config SYS_I2C_THUNDERX
+ bool "ThunderX i2c driver"
+ depends on ARCH_THUNDERX && DM_I2C
+ default y
+ help
+ Enable I2C support for Cavium ThunderX line of processors.
+
config SYS_I2C_S3C24X0
bool "Samsung I2C driver"
depends on ARCH_EXYNOS4 && DM_I2C
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index d3637bcd8d..27087f1814 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -34,6 +34,7 @@ obj-$(CONFIG_SYS_I2C_SH) += sh_i2c.o
obj-$(CONFIG_SYS_I2C_SOFT) += soft_i2c.o
obj-$(CONFIG_SYS_I2C_STM32F7) += stm32f7_i2c.o
obj-$(CONFIG_SYS_I2C_TEGRA) += tegra_i2c.o
+obj-$(CONFIG_SYS_I2C_THUNDERX) += thunderx_i2c.o
obj-$(CONFIG_SYS_I2C_UNIPHIER) += i2c-uniphier.o
obj-$(CONFIG_SYS_I2C_UNIPHIER_F) += i2c-uniphier-f.o
obj-$(CONFIG_SYS_I2C_VERSATILE) += i2c-versatile.o
diff --git a/drivers/i2c/thunderx_i2c.c b/drivers/i2c/thunderx_i2c.c
new file mode 100644
index 0000000000..bac442d3fa
--- /dev/null
+++ b/drivers/i2c/thunderx_i2c.c
@@ -0,0 +1,878 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, Cavium Inc.
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <dm.h>
+#include <asm/io.h>
+#include <asm/arch-thunderx/thunderx.h>
+
+/*
+ * Slave address to use for Thunder when accessed by another master
+ */
+#ifndef CONFIG_SYS_I2C_THUNDERX_SLAVE_ADDR
+# define CONFIG_SYS_I2C_THUNDERX_SLAVE_ADDR 0x77
+#endif
+
+#define TWSI_THP 24
+
+#define TWSI_SW_TWSI 0x1000
+#define TWSI_TWSI_SW 0x1008
+#define TWSI_INT 0x1010
+#define TWSI_SW_TWSI_EXT 0x1018
+
+union twsx_sw_twsi {
+ u64 u;
+ struct {
+ u64 data:32;
+ u64 eop_ia:3;
+ u64 ia:5;
+ u64 addr:10;
+ u64 scr:2;
+ u64 size:3;
+ u64 sovr:1;
+ u64 r:1;
+ u64 op:4;
+ u64 eia:1;
+ u64 slonly:1;
+ u64 v:1;
+ } s;
+};
+
+union twsx_sw_twsi_ext {
+ u64 u;
+ struct {
+ u64 data:32;
+ u64 ia:8;
+ u64 :24;
+ } s;
+};
+
+union twsx_int {
+ u64 u;
+ struct {
+ u64 st_int:1; /** TWSX_SW_TWSI register update int */
+ u64 ts_int:1; /** TWSX_TWSI_SW register update int */
+ u64 core_int:1; /** TWSI core interrupt, ignored for HLC */
+ u64 :5; /** Reserved */
+ u64 sda_ovr:1; /** SDA testing override */
+ u64 scl_ovr:1; /** SCL testing override */
+ u64 sda:1; /** SDA signal */
+ u64 scl:1; /** SCL signal */
+ u64 :52; /** Reserved */
+ } s;
+};
+
+enum {
+ TWSI_OP_WRITE = 0,
+ TWSI_OP_READ = 1,
+};
+
+enum {
+ TWSI_EOP_SLAVE_ADDR = 0,
+ TWSI_EOP_CLK_CTL = 3,
+ TWSI_SW_EOP_IA = 6,
+};
+
+enum {
+ TWSI_SLAVEADD = 0,
+ TWSI_DATA = 1,
+ TWSI_CTL = 2,
+ TWSI_CLKCTL = 3,
+ TWSI_STAT = 3,
+ TWSI_SLAVEADD_EXT = 4,
+ TWSI_RST = 7,
+};
+
+enum {
+ TWSI_CTL_AAK = BIT(2),
+ TWSI_CTL_IFLG = BIT(3),
+ TWSI_CTL_STP = BIT(4),
+ TWSI_CTL_STA = BIT(5),
+ TWSI_CTL_ENAB = BIT(6),
+ TWSI_CTL_CE = BIT(7),
+};
+
+enum {
+ /** Bus error */
+ TWSI_STAT_BUS_ERROR = 0x00,
+ /** Start condition transmitted */
+ TWSI_STAT_START = 0x08,
+ /** Repeat start condition transmitted */
+ TWSI_STAT_RSTART = 0x10,
+ /** Address + write bit transmitted, ACK received */
+ TWSI_STAT_TXADDR_ACK = 0x18,
+ /** Address + write bit transmitted, /ACK received */
+ TWSI_STAT_TXADDR_NAK = 0x20,
+ /** Data byte transmitted in master mode, ACK received */
+ TWSI_STAT_TXDATA_ACK = 0x28,
+ /** Data byte transmitted in master mode, ACK received */
+ TWSI_STAT_TXDATA_NAK = 0x30,
+ /** Arbitration lost in address or data byte */
+ TWSI_STAT_TX_ARB_LOST = 0x38,
+ /** Address + read bit transmitted, ACK received */
+ TWSI_STAT_RXADDR_ACK = 0x40,
+ /** Address + read bit transmitted, /ACK received */
+ TWSI_STAT_RXADDR_NAK = 0x48,
+ /** Data byte received in master mode, ACK transmitted */
+ TWSI_STAT_RXDATA_ACK_SENT = 0x50,
+ /** Data byte received, NACK transmitted */
+ TWSI_STAT_RXDATA_NAK_SENT = 0x58,
+ /** Slave address received, sent ACK */
+ TWSI_STAT_SLAVE_RXADDR_ACK = 0x60,
+ /**
+ * Arbitration lost in address as master, slave address + write bit
+ * received, ACK transmitted
+ */
+ TWSI_STAT_TX_ACK_ARB_LOST = 0x68,
+ /** General call address received, ACK transmitted */
+ TWSI_STAT_RX_GEN_ADDR_ACK = 0x70,
+ /**
+ * Arbitration lost in address as master, general call address
+ * received, ACK transmitted
+ */
+ TWSI_STAT_RX_GEN_ADDR_ARB_LOST = 0x78,
+ /** Data byte received after slave address received, ACK transmitted */
+ TWSI_STAT_SLAVE_RXDATA_ACK = 0x80,
+ /** Data byte received after slave address received, /ACK transmitted */
+ TWSI_STAT_SLAVE_RXDATA_NAK = 0x88,
+ /**
+ * Data byte received after general call address received, ACK
+ * transmitted
+ */
+ TWSI_STAT_GEN_RXADDR_ACK = 0x90,
+ /**
+ * Data byte received after general call address received, /ACK
+ * transmitted
+ */
+ TWSI_STAT_GEN_RXADDR_NAK = 0x98,
+ /** STOP or repeated START condition received in slave mode */
+ TWSI_STAT_STOP_MULTI_START = 0xA0,
+ /** Slave address + read bit received, ACK transmitted */
+ TWSI_STAT_SLAVE_RXADDR2_ACK = 0xA8,
+ /**
+ * Arbitration lost in address as master, slave address + read bit
+ * received, ACK transmitted
+ */
+ TWSI_STAT_RXDATA_ACK_ARB_LOST = 0xB0,
+ /** Data byte transmitted in slave mode, ACK received */
+ TWSI_STAT_SLAVE_TXDATA_ACK = 0xB8,
+ /** Data byte transmitted in slave mode, /ACK received */
+ TWSI_STAT_SLAVE_TXDATA_NAK = 0xC0,
+ /** Last byte transmitted in slave mode, ACK received */
+ TWSI_STAT_SLAVE_TXDATA_END_ACK = 0xC8,
+ /** Second address byte + write bit transmitted, ACK received */
+ TWSI_STAT_TXADDR2DATA_ACK = 0xD0,
+ /** Second address byte + write bit transmitted, /ACK received */
+ TWSI_STAT_TXADDR2DATA_NAK = 0xD8,
+ /** No relevant status information */
+ TWSI_STAT_IDLE = 0xF8
+};
+
+struct thunderx_twsi {
+ int id;
+ int speed;
+ void *baseaddr;
+};
+
+/** Last i2c id assigned */
+static int last_id = 0;
+
+static void twsi_unblock(void *baseaddr);
+static int twsi_stop(void *baseaddr);
+
+
+/**
+ * Converts the i2c status to a meaningful string
+ *
+ * @param status status to convert
+ *
+ * @return string representation of the status
+ */
+static const char *twsi_i2c_status_str(uint8_t status)
+{
+ switch (status) {
+ case TWSI_STAT_BUS_ERROR:
+ return "Bus error";
+ case TWSI_STAT_START:
+ return "START condition transmitted";
+ case TWSI_STAT_RSTART:
+ return "Repeated START condition transmitted";
+ case TWSI_STAT_TXADDR_ACK:
+ return "Address + write bit transmitted, ACK received";
+ case TWSI_STAT_TXADDR_NAK:
+ return "Address + write bit transmitted, NAK received";
+ case TWSI_STAT_TXDATA_ACK:
+ return "Data byte transmitted in master mode, ACK received";
+ case TWSI_STAT_TXDATA_NAK:
+ return "Data byte transmitted in master mode, NAK received";
+ case TWSI_STAT_TX_ARB_LOST:
+ return "Arbitration lost in address or data byte";
+ case TWSI_STAT_RXADDR_ACK:
+ return "Address + read bit transmitted, ACK received";
+ case TWSI_STAT_RXADDR_NAK:
+ return "Address + read bit transmitted, NAK received";
+ case TWSI_STAT_RXDATA_ACK_SENT:
+ return "Data byte received in master mode, ACK transmitted";
+ case TWSI_STAT_RXDATA_NAK_SENT:
+ return "Data byte received in master mode, NAK transmitted";
+ case TWSI_STAT_SLAVE_RXADDR_ACK:
+ return "Slave address + write bit received, ACK transmitted";
+ case TWSI_STAT_TX_ACK_ARB_LOST:
+ return "Arbitration lost in address as master, slave address + write bit received, ACK transmitted";
+ case TWSI_STAT_RX_GEN_ADDR_ACK:
+ return "General call address received, ACK transmitted";
+ case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
+ return "Arbitration lost in address as master, general call address received, ACK transmitted";
+ case TWSI_STAT_SLAVE_RXDATA_ACK:
+ return "Data byte received after slave address received, ACK transmitted";
+ case TWSI_STAT_SLAVE_RXDATA_NAK:
+ return "Data byte received after slave address received, NAK transmitted";
+ case TWSI_STAT_GEN_RXADDR_ACK:
+ return "Data byte received after general call address received, ACK transmitted";
+ case TWSI_STAT_GEN_RXADDR_NAK:
+ return "Data byte received after general call address received, NAK transmitted";
+ case TWSI_STAT_STOP_MULTI_START:
+ return "STOP or repeated START condition received in slave mode";
+ case TWSI_STAT_SLAVE_RXADDR2_ACK:
+ return "Slave address + read bit received, ACK transmitted";
+ case TWSI_STAT_RXDATA_ACK_ARB_LOST:
+ return "Arbitration lost in address as master, slave address + read bit received, ACK transmitted";
+ case TWSI_STAT_SLAVE_TXDATA_ACK:
+ return "Data byte transmitted in slave mode, ACK received";
+ case TWSI_STAT_SLAVE_TXDATA_NAK:
+ return "Data byte transmitted in slave mode, NAK received";
+ case TWSI_STAT_SLAVE_TXDATA_END_ACK:
+ return "Last byte transmitted in slave mode, ACK received";
+ case TWSI_STAT_TXADDR2DATA_ACK:
+ return "Second address byte + write bit transmitted, ACK received";
+ case TWSI_STAT_TXADDR2DATA_NAK:
+ return "Second address byte + write bit transmitted, NAK received";
+ case TWSI_STAT_IDLE:
+ return "Idle";
+ default:
+ return "Unknown status code";
+ }
+}
+
+/**
+ * Returns true if we lost arbitration
+ *
+ * @param code status code
+ * @param final_read true if this is the final read operation
+ *
+ * @return true if arbitration has been lost, false if it hasn't been lost.
+ */
+static int twsi_i2c_lost_arb(u8 code, int final_read)
+{
+ switch (code) {
+ /* Arbitration lost */
+ case TWSI_STAT_TX_ARB_LOST:
+ case TWSI_STAT_TX_ACK_ARB_LOST:
+ case TWSI_STAT_RX_GEN_ADDR_ARB_LOST:
+ case TWSI_STAT_RXDATA_ACK_ARB_LOST:
+ return -EAGAIN;
+
+ /* Being addressed as slave, should back off and listen */
+ case TWSI_STAT_SLAVE_RXADDR_ACK:
+ case TWSI_STAT_RX_GEN_ADDR_ACK:
+ case TWSI_STAT_GEN_RXADDR_ACK:
+ case TWSI_STAT_GEN_RXADDR_NAK:
+ return -EIO;
+
+ /* Core busy as slave */
+ case TWSI_STAT_SLAVE_RXDATA_ACK:
+ case TWSI_STAT_SLAVE_RXDATA_NAK:
+ case TWSI_STAT_STOP_MULTI_START:
+ case TWSI_STAT_SLAVE_RXADDR2_ACK:
+ case TWSI_STAT_SLAVE_TXDATA_ACK:
+ case TWSI_STAT_SLAVE_TXDATA_NAK:
+ case TWSI_STAT_SLAVE_TXDATA_END_ACK:
+ return -EIO;
+
+ /* Ack allowed on pre-terminal bytes only */
+ case TWSI_STAT_RXDATA_ACK_SENT:
+ if (!final_read)
+ return 0;
+ return -EAGAIN;
+
+ /* NAK allowed on terminal byte only */
+ case TWSI_STAT_RXDATA_NAK_SENT:
+ if (!final_read)
+ return 0;
+ return -EAGAIN;
+
+ case TWSI_STAT_TXDATA_NAK:
+ case TWSI_STAT_TXADDR_NAK:
+ case TWSI_STAT_RXADDR_NAK:
+ case TWSI_STAT_TXADDR2DATA_NAK:
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+/**
+ * Writes to the MIO_TWS(0..5)_SW_TWSI register
+ *
+ * @param baseaddr Base address of i2c registers
+ * @param sw_twsi value to write
+ *
+ * @return 0 for success, otherwise error
+ */
+static u64 twsi_write_sw(void *baseaddr, union twsx_sw_twsi sw_twsi)
+{
+ unsigned long start = get_timer(0);
+
+ sw_twsi.s.r = 0;
+ sw_twsi.s.v = 1;
+
+ debug("%s(%p, 0x%llx)\n", __func__, baseaddr, sw_twsi.u);
+ writeq(sw_twsi.u, baseaddr + TWSI_SW_TWSI);
+ do {
+ sw_twsi.u = readq(baseaddr + TWSI_SW_TWSI);
+ } while (sw_twsi.s.v != 0 && get_timer(start) < 50);
+
+ if (sw_twsi.s.v)
+ debug("%s: timed out\n", __func__);
+ return sw_twsi.u;
+}
+
+/**
+ * Reads the MIO_TWS(0..5)_SW_TWSI register
+ *
+ * @param baseaddr Base address of i2c registers
+ * @param sw_twsi value for eia and op, etc. to read
+ *
+ * @return value of the register
+ */
+static u64 twsi_read_sw(void *baseaddr, union twsx_sw_twsi sw_twsi)
+{
+ unsigned long start = get_timer(0);
+ sw_twsi.s.r = 1;
+ sw_twsi.s.v = 1;
+
+ debug("%s(%p, 0x%llx)\n", __func__, baseaddr, sw_twsi.u);
+ writeq(sw_twsi.u, baseaddr + TWSI_SW_TWSI);
+
+ do {
+ sw_twsi.u = readq(baseaddr + TWSI_SW_TWSI);
+ } while (sw_twsi.s.v != 0 && get_timer(start) < 50);
+
+ if (sw_twsi.s.v)
+ debug("%s: Error writing 0x%llx\n", __func__, sw_twsi.u);
+
+ debug("%s: Returning 0x%llx\n", __func__, sw_twsi.u);
+ return sw_twsi.u;
+}
+
+/**
+ * Write control register
+ *
+ * @param baseaddr Base address for i2c registers
+ * @param data data to write
+ */
+static void twsi_write_ctl(void *baseaddr, u8 data)
+{
+ union twsx_sw_twsi twsi_sw;
+
+ debug("%s(%p, 0x%x)\n", __func__, baseaddr, data);
+ twsi_sw.u = 0;
+
+ twsi_sw.s.op = TWSI_SW_EOP_IA;
+ twsi_sw.s.eop_ia = TWSI_CTL;
+ twsi_sw.s.data = data;
+
+ twsi_write_sw(baseaddr, twsi_sw);
+}
+
+/**
+ * Reads the TWSI Control Register
+ *
+ * @param[in] baseaddr Base address for i2c
+ *
+ * @return 8-bit TWSI control register
+ */
+static u32 twsi_read_ctl(void *baseaddr)
+{
+ union twsx_sw_twsi sw_twsi;
+
+ sw_twsi.u = 0;
+ sw_twsi.s.op = TWSI_SW_EOP_IA;
+ sw_twsi.s.eop_ia = TWSI_CTL;
+
+ sw_twsi.u = twsi_read_sw(baseaddr, sw_twsi);
+ debug("%s(%p): 0x%x\n", __func__, baseaddr, sw_twsi.s.data);
+ return sw_twsi.s.data;
+}
+
+/**
+ * Read i2c status register
+ *
+ * @param baseaddr Base address of i2c registers
+ *
+ * @return value of status register
+ */
+static u8 twsi_read_status(void *baseaddr)
+{
+ union twsx_sw_twsi twsi_sw;
+
+ twsi_sw.u = 0;
+ twsi_sw.s.op = TWSI_SW_EOP_IA;
+ twsi_sw.s.eop_ia = TWSI_STAT;
+
+ return twsi_read_sw(baseaddr, twsi_sw);
+}
+
+/**
+ * Waits for an i2c operation to complete
+ *
+ * @param baseaddr Base address of registers
+ *
+ * @return 0 for success, 1 if timeout
+ */
+static int twsi_wait(void *baseaddr)
+{
+ unsigned long start = get_timer(0);
+ u8 twsi_ctl;
+
+ debug("%s(%p)\n", __func__, baseaddr);
+ do {
+ twsi_ctl = twsi_read_ctl(baseaddr);
+ twsi_ctl &= TWSI_CTL_IFLG;
+ } while (!twsi_ctl && get_timer(start) < 50);
+
+ debug(" return: %u\n", !twsi_ctl);
+ return !twsi_ctl;
+}
+
+/**
+ * Unsticks the i2c bus
+ *
+ * @param baseaddr base address of registers
+ */
+static int twsi_start_unstick(void *baseaddr)
+{
+ twsi_stop(baseaddr);
+
+ twsi_unblock(baseaddr);
+
+ return 0;
+}
+
+/**
+ * Sends an i2c start condition
+ *
+ * @param baseaddr base address of registers
+ *
+ * @return 0 for success, otherwise error
+ */
+static int twsi_start(void *baseaddr)
+{
+ int result;
+ u8 stat;
+
+ debug("%s(%p)\n", __func__, baseaddr);
+ twsi_write_ctl(baseaddr, TWSI_CTL_STA | TWSI_CTL_ENAB);
+ result = twsi_wait(baseaddr);
+ if (result) {
+ stat = twsi_read_status(baseaddr);
+ debug("%s: result: 0x%x, status: 0x%x\n", __func__,
+ result, stat);
+ switch (stat) {
+ case TWSI_STAT_START:
+ case TWSI_STAT_RSTART:
+ return 0;
+ case TWSI_STAT_RXADDR_ACK:
+ default:
+ return twsi_start_unstick(baseaddr);
+ }
+ }
+ debug("%s: success\n", __func__);
+ return 0;
+}
+
+/**
+ * Sends an i2c stop condition
+ *
+ * @param baseaddr register base address
+ *
+ * @return 0 for success, -1 if error
+ */
+static int twsi_stop(void *baseaddr)
+{
+ u8 stat;
+ twsi_write_ctl(baseaddr, TWSI_CTL_STP | TWSI_CTL_ENAB);
+
+ stat = twsi_read_status(baseaddr);
+ if (stat != TWSI_STAT_IDLE) {
+ debug("%s: Bad status on bus@%p\n", __func__, baseaddr);
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ * Writes data to the i2c bus
+ *
+ * @param baseraddr register base address
+ * @param slave_addr address of slave to write to
+ * @param buffer Pointer to buffer to write
+ * @param length Number of bytes in buffer to write
+ *
+ * @return 0 for success, otherwise error
+ */
+static int twsi_write_data(void *baseaddr, u8 slave_addr,
+ u8 *buffer, unsigned int length)
+{
+ union twsx_sw_twsi twsi_sw;
+ unsigned int curr = 0;
+ int result;
+
+ debug("%s(%p, 0x%x, %p, 0x%x)\n", __func__, baseaddr, slave_addr,
+ buffer, length);
+ result = twsi_start(baseaddr);
+ if (result) {
+ debug("%s: Could not start BUS transaction\n", __func__);
+ return -1;
+ }
+
+ result = twsi_wait(baseaddr);
+ if (result) {
+ debug("%s: wait failed\n", __func__);
+ return result;
+ }
+
+ twsi_sw.u = 0;
+ twsi_sw.s.op = TWSI_SW_EOP_IA;
+ twsi_sw.s.eop_ia = TWSI_DATA;
+ twsi_sw.s.data = (u32) (slave_addr << 1) | TWSI_OP_WRITE;
+
+ twsi_write_sw(baseaddr, twsi_sw);
+ twsi_write_ctl(baseaddr, TWSI_CTL_ENAB);
+
+ debug("%s: Waiting\n", __func__);
+ result = twsi_wait(baseaddr);
+ if (result) {
+ debug("%s: Timed out writing slave address 0x%x to target\n",
+ __func__, slave_addr);
+ return result;
+ }
+ result = twsi_read_status(baseaddr);
+ debug("%s: status: (%d) %s\n", __func__, result,
+ twsi_i2c_status_str(result));
+ if ((result = twsi_read_status(baseaddr)) != TWSI_STAT_TXADDR_ACK) {
+ debug("%s: status: (%d) %s\n", __func__, result,
+ twsi_i2c_status_str(result));
+ twsi_stop(baseaddr);
+ return twsi_i2c_lost_arb(result, 0);
+ }
+
+ while (curr < length) {
+ twsi_sw.u = 0;
+ twsi_sw.s.op = TWSI_SW_EOP_IA;
+ twsi_sw.s.eop_ia = TWSI_DATA;
+ twsi_sw.s.data = buffer[curr++];
+
+ twsi_write_sw(baseaddr, twsi_sw);
+ twsi_write_ctl(baseaddr, TWSI_CTL_ENAB);
+
+ debug("%s: Writing 0x%x\n", __func__, twsi_sw.s.data);
+
+ result = twsi_wait(baseaddr);
+ if (result) {
+ debug("%s: Timed out writing data to 0x%x\n",
+ __func__, slave_addr);
+ return result;
+ }
+ result = twsi_read_status(baseaddr);
+ debug("%s: status: (%d) %s\n", __func__, result,
+ twsi_i2c_status_str(result));
+ }
+
+ debug("%s: Stopping\n", __func__);
+ return twsi_stop(baseaddr);
+}
+
+/**
+ * Manually clear the I2C bus and send a stop
+ */
+static void twsi_unblock(void *baseaddr)
+{
+ int i;
+ union twsx_int int_reg;
+
+ int_reg.u = 0;
+ for (i = 0; i < 9; i++) {
+ int_reg.s.scl_ovr = 0;
+ writeq(int_reg.u, baseaddr + TWSI_INT);
+ udelay(5);
+ int_reg.s.scl_ovr = 1;
+ writeq(int_reg.u, baseaddr + TWSI_INT);
+ udelay(5);
+ }
+ int_reg.s.sda_ovr = 1;
+ writeq(int_reg.u, baseaddr + TWSI_INT);
+ udelay(5);
+ int_reg.s.scl_ovr = 0;
+ writeq(int_reg.u, baseaddr + TWSI_INT);
+ udelay(5);
+ int_reg.u = 0;
+ writeq(int_reg.u, baseaddr + TWSI_INT);
+ udelay(5);
+}
+
+/**
+ * Performs a read transaction on the i2c bus
+ *
+ * @param baseaddr Base address of twsi registers
+ * @param slave_addr i2c bus address to read from
+ * @param buffer buffer to read into
+ * @param length number of bytes to read
+ *
+ * @return 0 for success, otherwise error
+ */
+static int twsi_read_data(void *baseaddr, u8 slave_addr,
+ u8 *buffer, unsigned int length)
+{
+ union twsx_sw_twsi twsi_sw;
+ unsigned int curr = 0;
+ int result;
+
+ debug("%s(%p, 0x%x, %p, %u)\n", __func__, baseaddr, slave_addr,
+ buffer, length);
+ result = twsi_start(baseaddr);
+ if (result) {
+ debug("%s: start failed\n", __func__);
+ return result;
+ }
+
+ result = twsi_wait(baseaddr);
+ if (result) {
+ debug("%s: wait failed\n", __func__);
+ return result;
+ }
+
+ twsi_sw.u = 0;
+ twsi_sw.s.op = TWSI_SW_EOP_IA;
+ twsi_sw.s.eop_ia = TWSI_DATA;
+
+ twsi_sw.s.data = (u32) (slave_addr << 1) | TWSI_OP_READ;
+
+ twsi_write_sw(baseaddr, twsi_sw);
+ twsi_write_ctl(baseaddr, TWSI_CTL_ENAB);
+
+ result = twsi_wait(baseaddr);
+ if (result) {
+ debug("%s: waiting for sending addr failed\n", __func__);
+ return result;
+ }
+
+ result = twsi_read_status(baseaddr);
+ debug("%s: status: (%d) %s\n", __func__, result,
+ twsi_i2c_status_str(result));
+ if (result != TWSI_STAT_RXADDR_ACK) {
+ debug("%s: status: (%d) %s\n", __func__, result,
+ twsi_i2c_status_str(result));
+ twsi_stop(baseaddr);
+ return twsi_i2c_lost_arb(result, 0);
+ }
+
+ while (curr < length) {
+ twsi_write_ctl(baseaddr, TWSI_CTL_ENAB |
+ ((curr < length - 1) ? TWSI_CTL_AAK : 0));
+
+ result = twsi_wait(baseaddr);
+ if (result) {
+ debug("%s: waiting for data failed\n", __func__);
+ return result;
+ }
+
+ twsi_sw.u = twsi_read_sw(baseaddr, twsi_sw);
+ buffer[curr++] = twsi_sw.s.data;
+ }
+
+ twsi_stop(baseaddr);
+
+ return 0;
+}
+
+static int twsi_init(void *baseaddr, unsigned int speed, int slaveaddr)
+{
+ int io_clock_hz;
+ int n_div;
+ int m_div;
+ union twsx_sw_twsi sw_twsi;
+
+ debug("%s(%p, %u, 0x%x)\n", __func__, baseaddr, speed, slaveaddr);
+ io_clock_hz = thunderx_get_io_clock();
+
+ /* Set the TWSI clock to a conservative TWSI_BUS_FREQ. Compute the
+ * clocks M divider based on the SCLK.
+ * TWSI freq = (core freq) / (20 x (M+1) x (thp+1) x 2^N)
+ * M = ((core freq) / (20 x (TWSI freq) x (thp+1) x 2^N)) - 1
+ */
+ for (n_div = 0; n_div < 8; n_div++) {
+ m_div = io_clock_hz / (20 * speed * (TWSI_THP + 1));
+ m_div /= 1 << n_div;
+ m_div -= 1;
+ if (m_div < 16)
+ break;
+ }
+ if (m_div >= 16)
+ return -1;
+
+ sw_twsi.u = 0;
+ sw_twsi.s.v = 1; /* Clear valid bit */
+ sw_twsi.s.op = 0x6; /* See EOP field */
+ sw_twsi.s.r = 0; /* Select CLKCTL when R = 0 */
+ sw_twsi.s.eop_ia = 3; /* R=0 selects CLKCTL, R=1 selects STAT */
+ sw_twsi.s.data = ((m_div & 0xf) << 3) | ((n_div & 0x7) << 0);
+
+ twsi_write_sw(baseaddr, sw_twsi);
+ /* Only init non-slave ports */
+ debug("%s: Writing 0x%llx to sw_twsi, m_div: 0x%x, n_div: 0x%x\n",
+ __func__, sw_twsi.u, m_div, n_div);
+
+
+ sw_twsi.u = 0;
+ sw_twsi.s.v = 1;
+ sw_twsi.s.op = TWSI_SW_EOP_IA;
+ sw_twsi.s.r = 0;
+ sw_twsi.s.eop_ia = 0;
+ sw_twsi.s.data = slaveaddr << 1;
+
+ twsi_write_sw(baseaddr, sw_twsi);
+
+ /* Set slave address */
+ sw_twsi.u = 0;
+ sw_twsi.s.v = 1;
+ sw_twsi.s.op = TWSI_SW_EOP_IA;
+ sw_twsi.s.r = 0;
+ sw_twsi.s.eop_ia = TWSI_EOP_SLAVE_ADDR;
+ sw_twsi.s.data = slaveaddr;
+ twsi_write_sw(baseaddr, sw_twsi);
+
+ return 0;
+}
+
+/**
+ * Transfers data over the i2c bus
+ *
+ * @param bus i2c bus to transfer data over
+ * @param msg Array of i2c messages
+ * @param nmsgs Number of messages to send/receive
+ *
+ * @return 0 for success, otherwise error
+ */
+static int thunderx_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
+ int nmsgs)
+{
+ struct thunderx_twsi *twsi = dev_get_priv(bus);
+ int result;
+
+ debug("thunderx_i2c_xfer: %d messages\n", nmsgs);
+ for (; nmsgs > 0; nmsgs--, msg++) {
+ debug("thunderx_i2c_xfer: chip=0x%x, len=0x%x\n",
+ msg->addr, msg->len);
+ if (msg->flags & I2C_M_RD) {
+ debug("%s: Reading data\n", __func__);
+ result = twsi_read_data(twsi->baseaddr, msg->addr,
+ msg->buf, msg->len);
+ } else {
+ debug("%s: Writing data\n", __func__);
+ result = twsi_write_data(twsi->baseaddr, msg->addr,
+ msg->buf, msg->len);
+ }
+ if (result) {
+ debug("thunderx_i2c_xfer: error sending\n");
+ return -EREMOTEIO;
+ }
+ }
+
+ return 0;
+}
+
+static int thunderx_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+{
+ struct thunderx_twsi *twsi = dev_get_priv(bus);
+ int m_div, n_div;
+ unsigned io_clock_hz;
+ union twsx_sw_twsi sw_twsi;
+ void *baseaddr = twsi->baseaddr;
+
+ io_clock_hz = thunderx_get_io_clock();
+ debug("%s(%p, %u) io clock: %u\n", __func__, bus, speed, io_clock_hz);
+
+ /* Set the TWSI clock to a conservative TWSI_BUS_FREQ. Compute the
+ * clocks M divider based on the SCLK.
+ * TWSI freq = (core freq) / (20 x (M+1) x (thp+1) x 2^N)
+ * M = ((core freq) / (20 x (TWSI freq) x (thp+1) x 2^N)) - 1 */
+ for (n_div = 0; n_div < 8; n_div++) {
+ m_div = io_clock_hz / (20 * speed * (TWSI_THP + 1));
+ m_div /= 1 << n_div;
+ m_div -= 1;
+ if (m_div < 16)
+ break;
+ }
+ if (m_div >= 16)
+ return -1;
+
+ sw_twsi.u = 0;
+ sw_twsi.s.v = 1; /* Clear valid bit */
+ sw_twsi.s.op = TWSI_SW_EOP_IA; /* See EOP field */
+ sw_twsi.s.r = 0; /* Select CLKCTL when R = 0 */
+ sw_twsi.s.eop_ia = TWSI_CLKCTL; /* R=0 selects CLKCTL, R=1 selects STAT */
+ sw_twsi.s.data = ((m_div & 0xf) << 3) | ((n_div & 0x7) << 0);
+
+ /* Only init non-slave ports */
+ writeq(sw_twsi.u, baseaddr + TWSI_SW_TWSI);
+
+ debug("%s: Wrote 0x%llx to sw_twsi\n", __func__, sw_twsi.u);
+ return 0;
+}
+
+static int thunderx_pci_i2c_probe(struct udevice *dev)
+{
+ struct thunderx_twsi *twsi = dev_get_priv(dev);
+ size_t size;
+ pci_dev_t bdf = dm_pci_get_bdf(dev);
+
+ debug("TWSI PCI device: %x\n", bdf);
+ dev->req_seq = PCI_FUNC(bdf);
+
+ twsi->baseaddr = dm_pci_map_bar(dev, 0, &size, PCI_REGION_MEM);
+ twsi->id = last_id++;
+
+ debug("TWSI bus %d at %p\n",dev->seq, twsi->baseaddr);
+
+ return twsi_init(twsi->baseaddr, CONFIG_SYS_I2C_SPEED,
+ CONFIG_SYS_I2C_THUNDERX_SLAVE_ADDR);
+}
+
+static const struct dm_i2c_ops thunderx_i2c_ops = {
+ .xfer = thunderx_i2c_xfer,
+ .set_bus_speed = thunderx_i2c_set_bus_speed,
+};
+
+static const struct udevice_id thunderx_i2c_ids[] = {
+ { .compatible = "cavium,thunder-8890-twsi" },
+ { }
+};
+
+U_BOOT_DRIVER(thunderx_pci_twsi) = {
+ .name = "i2c_thunderx",
+ .id = UCLASS_I2C,
+ .of_match = thunderx_i2c_ids,
+ .probe = thunderx_pci_i2c_probe,
+ .priv_auto_alloc_size = sizeof(struct thunderx_twsi),
+ .ops = &thunderx_i2c_ops,
+};
+
+static struct pci_device_id thunderx_pci_twsi_supported[] = {
+ { PCI_VDEVICE(CAVIUM, PCI_DEVICE_ID_THUNDERX_TWSI) },
+ { },
+};
+
+U_BOOT_PCI_DEVICE(thunderx_pci_twsi, thunderx_pci_twsi_supported);
diff --git a/include/configs/thunderx_81xx.h b/include/configs/thunderx_81xx.h
index 10c4a89232..7a2c0adde2 100644
--- a/include/configs/thunderx_81xx.h
+++ b/include/configs/thunderx_81xx.h
@@ -68,4 +68,6 @@
#define PLL_REF_CLK 50000000 /* 50 MHz */
#define NS_PER_REF_CLK_TICK (1000000000/PLL_REF_CLK)
+#define CONFIG_SYS_I2C_SPEED 100000
+
#endif /* __THUNDERX_81XX_H__ */
--
2.17.1
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