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Diffstat (limited to 'drivers/i2c/busses/i2c-octeon-core.h')
-rw-r--r--drivers/i2c/busses/i2c-octeon-core.h219
1 files changed, 219 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-octeon-core.h b/drivers/i2c/busses/i2c-octeon-core.h
new file mode 100644
index 000000000..9bb9f64fd
--- /dev/null
+++ b/drivers/i2c/busses/i2c-octeon-core.h
@@ -0,0 +1,219 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/atomic.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+
+/* Controller command patterns */
+#define SW_TWSI_V BIT_ULL(63) /* Valid bit */
+#define SW_TWSI_EIA BIT_ULL(61) /* Extended internal address */
+#define SW_TWSI_R BIT_ULL(56) /* Result or read bit */
+#define SW_TWSI_SOVR BIT_ULL(55) /* Size override */
+#define SW_TWSI_SIZE_SHIFT 52
+#define SW_TWSI_ADDR_SHIFT 40
+#define SW_TWSI_IA_SHIFT 32 /* Internal address */
+
+/* Controller opcode word (bits 60:57) */
+#define SW_TWSI_OP_SHIFT 57
+#define SW_TWSI_OP_7 (0ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_7_IA (1ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_10 (2ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_10_IA (3ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_TWSI_CLK (4ULL << SW_TWSI_OP_SHIFT)
+#define SW_TWSI_OP_EOP (6ULL << SW_TWSI_OP_SHIFT) /* Extended opcode */
+
+/* Controller extended opcode word (bits 34:32) */
+#define SW_TWSI_EOP_SHIFT 32
+#define SW_TWSI_EOP_TWSI_DATA (SW_TWSI_OP_EOP | 1ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_CTL (SW_TWSI_OP_EOP | 2ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_CLKCTL (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_STAT (SW_TWSI_OP_EOP | 3ULL << SW_TWSI_EOP_SHIFT)
+#define SW_TWSI_EOP_TWSI_RST (SW_TWSI_OP_EOP | 7ULL << SW_TWSI_EOP_SHIFT)
+
+/* Controller command and status bits */
+#define TWSI_CTL_CE 0x80 /* High level controller enable */
+#define TWSI_CTL_ENAB 0x40 /* Bus enable */
+#define TWSI_CTL_STA 0x20 /* Master-mode start, HW clears when done */
+#define TWSI_CTL_STP 0x10 /* Master-mode stop, HW clears when done */
+#define TWSI_CTL_IFLG 0x08 /* HW event, SW writes 0 to ACK */
+#define TWSI_CTL_AAK 0x04 /* Assert ACK */
+
+/* Status values */
+#define STAT_BUS_ERROR 0x00
+#define STAT_START 0x08
+#define STAT_REP_START 0x10
+#define STAT_TXADDR_ACK 0x18
+#define STAT_TXADDR_NAK 0x20
+#define STAT_TXDATA_ACK 0x28
+#define STAT_TXDATA_NAK 0x30
+#define STAT_LOST_ARB_38 0x38
+#define STAT_RXADDR_ACK 0x40
+#define STAT_RXADDR_NAK 0x48
+#define STAT_RXDATA_ACK 0x50
+#define STAT_RXDATA_NAK 0x58
+#define STAT_SLAVE_60 0x60
+#define STAT_LOST_ARB_68 0x68
+#define STAT_SLAVE_70 0x70
+#define STAT_LOST_ARB_78 0x78
+#define STAT_SLAVE_80 0x80
+#define STAT_SLAVE_88 0x88
+#define STAT_GENDATA_ACK 0x90
+#define STAT_GENDATA_NAK 0x98
+#define STAT_SLAVE_A0 0xA0
+#define STAT_SLAVE_A8 0xA8
+#define STAT_LOST_ARB_B0 0xB0
+#define STAT_SLAVE_LOST 0xB8
+#define STAT_SLAVE_NAK 0xC0
+#define STAT_SLAVE_ACK 0xC8
+#define STAT_AD2W_ACK 0xD0
+#define STAT_AD2W_NAK 0xD8
+#define STAT_IDLE 0xF8
+
+/* TWSI_INT values */
+#define TWSI_INT_ST_INT BIT_ULL(0)
+#define TWSI_INT_TS_INT BIT_ULL(1)
+#define TWSI_INT_CORE_INT BIT_ULL(2)
+#define TWSI_INT_ST_EN BIT_ULL(4)
+#define TWSI_INT_TS_EN BIT_ULL(5)
+#define TWSI_INT_CORE_EN BIT_ULL(6)
+#define TWSI_INT_SDA_OVR BIT_ULL(8)
+#define TWSI_INT_SCL_OVR BIT_ULL(9)
+#define TWSI_INT_SDA BIT_ULL(10)
+#define TWSI_INT_SCL BIT_ULL(11)
+
+#define I2C_OCTEON_EVENT_WAIT 80 /* microseconds */
+
+/* Register offsets */
+struct octeon_i2c_reg_offset {
+ unsigned int sw_twsi;
+ unsigned int twsi_int;
+ unsigned int sw_twsi_ext;
+};
+
+#define SW_TWSI(x) (x->roff.sw_twsi)
+#define TWSI_INT(x) (x->roff.twsi_int)
+#define SW_TWSI_EXT(x) (x->roff.sw_twsi_ext)
+
+struct octeon_i2c {
+ wait_queue_head_t queue;
+ struct i2c_adapter adap;
+ struct octeon_i2c_reg_offset roff;
+ struct clk *clk;
+ int irq;
+ int hlc_irq; /* For cn7890 only */
+ u32 twsi_freq;
+ int sys_freq;
+ void __iomem *twsi_base;
+ struct device *dev;
+ bool hlc_enabled;
+ bool broken_irq_mode;
+ bool broken_irq_check;
+ void (*int_enable)(struct octeon_i2c *);
+ void (*int_disable)(struct octeon_i2c *);
+ void (*hlc_int_enable)(struct octeon_i2c *);
+ void (*hlc_int_disable)(struct octeon_i2c *);
+ atomic_t int_enable_cnt;
+ atomic_t hlc_int_enable_cnt;
+ struct i2c_smbus_alert_setup alert_data;
+ struct i2c_client *ara;
+};
+
+static inline void octeon_i2c_writeq_flush(u64 val, void __iomem *addr)
+{
+ __raw_writeq(val, addr);
+ __raw_readq(addr); /* wait for write to land */
+}
+
+/**
+ * octeon_i2c_reg_write - write an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ * @data: Value to be written
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static inline void octeon_i2c_reg_write(struct octeon_i2c *i2c, u64 eop_reg, u8 data)
+{
+ int tries = 1000;
+ u64 tmp;
+
+ __raw_writeq(SW_TWSI_V | eop_reg | data, i2c->twsi_base + SW_TWSI(i2c));
+ do {
+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ if (--tries < 0)
+ return;
+ } while ((tmp & SW_TWSI_V) != 0);
+}
+
+#define octeon_i2c_ctl_write(i2c, val) \
+ octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_CTL, val)
+#define octeon_i2c_data_write(i2c, val) \
+ octeon_i2c_reg_write(i2c, SW_TWSI_EOP_TWSI_DATA, val)
+
+/**
+ * octeon_i2c_reg_read - read lower bits of an I2C core register
+ * @i2c: The struct octeon_i2c
+ * @eop_reg: Register selector
+ *
+ * Returns the data.
+ *
+ * The I2C core registers are accessed indirectly via the SW_TWSI CSR.
+ */
+static inline int octeon_i2c_reg_read(struct octeon_i2c *i2c, u64 eop_reg,
+ int *error)
+{
+ int tries = 1000;
+ u64 tmp;
+
+ __raw_writeq(SW_TWSI_V | eop_reg | SW_TWSI_R, i2c->twsi_base + SW_TWSI(i2c));
+ do {
+ tmp = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+ if (--tries < 0) {
+ /* signal that the returned data is invalid */
+ if (error)
+ *error = -EIO;
+ return 0;
+ }
+ } while ((tmp & SW_TWSI_V) != 0);
+
+ return tmp & 0xFF;
+}
+
+#define octeon_i2c_ctl_read(i2c) \
+ octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_CTL, NULL)
+#define octeon_i2c_data_read(i2c, error) \
+ octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_DATA, error)
+#define octeon_i2c_stat_read(i2c) \
+ octeon_i2c_reg_read(i2c, SW_TWSI_EOP_TWSI_STAT, NULL)
+
+/**
+ * octeon_i2c_read_int - read the TWSI_INT register
+ * @i2c: The struct octeon_i2c
+ *
+ * Returns the value of the register.
+ */
+static inline u64 octeon_i2c_read_int(struct octeon_i2c *i2c)
+{
+ return __raw_readq(i2c->twsi_base + TWSI_INT(i2c));
+}
+
+/**
+ * octeon_i2c_write_int - write the TWSI_INT register
+ * @i2c: The struct octeon_i2c
+ * @data: Value to be written
+ */
+static inline void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
+{
+ octeon_i2c_writeq_flush(data, i2c->twsi_base + TWSI_INT(i2c));
+}
+
+/* Prototypes */
+irqreturn_t octeon_i2c_isr(int irq, void *dev_id);
+int octeon_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num);
+int octeon_i2c_init_lowlevel(struct octeon_i2c *i2c);
+void octeon_i2c_set_clock(struct octeon_i2c *i2c);
+extern struct i2c_bus_recovery_info octeon_i2c_recovery_info;