diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-mv64xxx.c')
-rw-r--r-- | drivers/i2c/busses/i2c-mv64xxx.c | 219 |
1 files changed, 200 insertions, 19 deletions
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c index b1f42bf40963..d3e9cc3153a9 100644 --- a/drivers/i2c/busses/i2c-mv64xxx.c +++ b/drivers/i2c/busses/i2c-mv64xxx.c @@ -21,9 +21,9 @@ #include <linux/of.h> #include <linux/of_device.h> #include <linux/of_irq.h> -#include <linux/of_i2c.h> #include <linux/clk.h> #include <linux/err.h> +#include <linux/delay.h> #define MV64XXX_I2C_ADDR_ADDR(val) ((val & 0x7f) << 1) #define MV64XXX_I2C_BAUD_DIV_N(val) (val & 0x7) @@ -55,6 +55,32 @@ #define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8 #define MV64XXX_I2C_STATUS_NO_STATUS 0xf8 +/* Register defines (I2C bridge) */ +#define MV64XXX_I2C_REG_TX_DATA_LO 0xc0 +#define MV64XXX_I2C_REG_TX_DATA_HI 0xc4 +#define MV64XXX_I2C_REG_RX_DATA_LO 0xc8 +#define MV64XXX_I2C_REG_RX_DATA_HI 0xcc +#define MV64XXX_I2C_REG_BRIDGE_CONTROL 0xd0 +#define MV64XXX_I2C_REG_BRIDGE_STATUS 0xd4 +#define MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE 0xd8 +#define MV64XXX_I2C_REG_BRIDGE_INTR_MASK 0xdC +#define MV64XXX_I2C_REG_BRIDGE_TIMING 0xe0 + +/* Bridge Control values */ +#define MV64XXX_I2C_BRIDGE_CONTROL_WR 0x00000001 +#define MV64XXX_I2C_BRIDGE_CONTROL_RD 0x00000002 +#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT 2 +#define MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT 0x00001000 +#define MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT 13 +#define MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT 16 +#define MV64XXX_I2C_BRIDGE_CONTROL_ENABLE 0x00080000 + +/* Bridge Status values */ +#define MV64XXX_I2C_BRIDGE_STATUS_ERROR 0x00000001 +#define MV64XXX_I2C_STATUS_OFFLOAD_ERROR 0xf0000001 +#define MV64XXX_I2C_STATUS_OFFLOAD_OK 0xf0000000 + + /* Driver states */ enum { MV64XXX_I2C_STATE_INVALID, @@ -71,14 +97,17 @@ enum { enum { MV64XXX_I2C_ACTION_INVALID, MV64XXX_I2C_ACTION_CONTINUE, + MV64XXX_I2C_ACTION_OFFLOAD_SEND_START, MV64XXX_I2C_ACTION_SEND_START, MV64XXX_I2C_ACTION_SEND_RESTART, + MV64XXX_I2C_ACTION_OFFLOAD_RESTART, MV64XXX_I2C_ACTION_SEND_ADDR_1, MV64XXX_I2C_ACTION_SEND_ADDR_2, MV64XXX_I2C_ACTION_SEND_DATA, MV64XXX_I2C_ACTION_RCV_DATA, MV64XXX_I2C_ACTION_RCV_DATA_STOP, MV64XXX_I2C_ACTION_SEND_STOP, + MV64XXX_I2C_ACTION_OFFLOAD_SEND_STOP, }; struct mv64xxx_i2c_regs { @@ -117,6 +146,9 @@ struct mv64xxx_i2c_data { spinlock_t lock; struct i2c_msg *msg; struct i2c_adapter adapter; + bool offload_enabled; +/* 5us delay in order to avoid repeated start timing violation */ + bool errata_delay; }; static struct mv64xxx_i2c_regs mv64xxx_i2c_regs_mv64xxx = { @@ -165,6 +197,77 @@ mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data, } } +static int mv64xxx_i2c_offload_msg(struct mv64xxx_i2c_data *drv_data) +{ + unsigned long data_reg_hi = 0; + unsigned long data_reg_lo = 0; + unsigned long ctrl_reg; + struct i2c_msg *msg = drv_data->msgs; + + drv_data->msg = msg; + drv_data->byte_posn = 0; + drv_data->bytes_left = msg->len; + drv_data->aborting = 0; + drv_data->rc = 0; + /* Only regular transactions can be offloaded */ + if ((msg->flags & ~(I2C_M_TEN | I2C_M_RD)) != 0) + return -EINVAL; + + /* Only 1-8 byte transfers can be offloaded */ + if (msg->len < 1 || msg->len > 8) + return -EINVAL; + + /* Build transaction */ + ctrl_reg = MV64XXX_I2C_BRIDGE_CONTROL_ENABLE | + (msg->addr << MV64XXX_I2C_BRIDGE_CONTROL_ADDR_SHIFT); + + if ((msg->flags & I2C_M_TEN) != 0) + ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_ADDR_EXT; + + if ((msg->flags & I2C_M_RD) == 0) { + u8 local_buf[8] = { 0 }; + + memcpy(local_buf, msg->buf, msg->len); + data_reg_lo = cpu_to_le32(*((u32 *)local_buf)); + data_reg_hi = cpu_to_le32(*((u32 *)(local_buf+4))); + + ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_WR | + (msg->len - 1) << MV64XXX_I2C_BRIDGE_CONTROL_TX_SIZE_SHIFT; + + writel(data_reg_lo, + drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_LO); + writel(data_reg_hi, + drv_data->reg_base + MV64XXX_I2C_REG_TX_DATA_HI); + + } else { + ctrl_reg |= MV64XXX_I2C_BRIDGE_CONTROL_RD | + (msg->len - 1) << MV64XXX_I2C_BRIDGE_CONTROL_RX_SIZE_SHIFT; + } + + /* Execute transaction */ + writel(ctrl_reg, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + + return 0; +} + +static void +mv64xxx_i2c_update_offload_data(struct mv64xxx_i2c_data *drv_data) +{ + struct i2c_msg *msg = drv_data->msg; + + if (msg->flags & I2C_M_RD) { + u32 data_reg_lo = readl(drv_data->reg_base + + MV64XXX_I2C_REG_RX_DATA_LO); + u32 data_reg_hi = readl(drv_data->reg_base + + MV64XXX_I2C_REG_RX_DATA_HI); + u8 local_buf[8] = { 0 }; + + *((u32 *)local_buf) = le32_to_cpu(data_reg_lo); + *((u32 *)(local_buf+4)) = le32_to_cpu(data_reg_hi); + memcpy(msg->buf, local_buf, msg->len); + } + +} /* ***************************************************************************** * @@ -177,6 +280,15 @@ mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data, static void mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data) { + if (drv_data->offload_enabled) { + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_TIMING); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_MASK); + } + writel(0, drv_data->reg_base + drv_data->reg_offsets.soft_reset); writel(MV64XXX_I2C_BAUD_DIV_M(drv_data->freq_m) | MV64XXX_I2C_BAUD_DIV_N(drv_data->freq_n), drv_data->reg_base + drv_data->reg_offsets.clock); @@ -283,6 +395,16 @@ mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status) drv_data->rc = -ENXIO; break; + case MV64XXX_I2C_STATUS_OFFLOAD_OK: + if (drv_data->send_stop || drv_data->aborting) { + drv_data->action = MV64XXX_I2C_ACTION_OFFLOAD_SEND_STOP; + drv_data->state = MV64XXX_I2C_STATE_IDLE; + } else { + drv_data->action = MV64XXX_I2C_ACTION_OFFLOAD_RESTART; + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_RESTART; + } + break; + default: dev_err(&drv_data->adapter.dev, "mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, " @@ -299,19 +421,29 @@ static void mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) { switch(drv_data->action) { + case MV64XXX_I2C_ACTION_OFFLOAD_RESTART: + mv64xxx_i2c_update_offload_data(drv_data); + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE); + /* FALLTHRU */ case MV64XXX_I2C_ACTION_SEND_RESTART: /* We should only get here if we have further messages */ BUG_ON(drv_data->num_msgs == 0); - drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START; - writel(drv_data->cntl_bits, - drv_data->reg_base + drv_data->reg_offsets.control); - drv_data->msgs++; drv_data->num_msgs--; + if (!(drv_data->offload_enabled && + mv64xxx_i2c_offload_msg(drv_data))) { + drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START; + writel(drv_data->cntl_bits, + drv_data->reg_base + drv_data->reg_offsets.control); - /* Setup for the next message */ - mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs); + /* Setup for the next message */ + mv64xxx_i2c_prepare_for_io(drv_data, drv_data->msgs); + } + if (drv_data->errata_delay) + udelay(5); /* * We're never at the start of the message here, and by this @@ -326,6 +458,12 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) drv_data->reg_base + drv_data->reg_offsets.control); break; + case MV64XXX_I2C_ACTION_OFFLOAD_SEND_START: + if (!mv64xxx_i2c_offload_msg(drv_data)) + break; + else + drv_data->action = MV64XXX_I2C_ACTION_SEND_START; + /* FALLTHRU */ case MV64XXX_I2C_ACTION_SEND_START: writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START, drv_data->reg_base + drv_data->reg_offsets.control); @@ -366,6 +504,9 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP, drv_data->reg_base + drv_data->reg_offsets.control); drv_data->block = 0; + if (drv_data->errata_delay) + udelay(5); + wake_up(&drv_data->waitq); break; @@ -375,6 +516,7 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) "mv64xxx_i2c_do_action: Invalid action: %d\n", drv_data->action); drv_data->rc = -EIO; + /* FALLTHRU */ case MV64XXX_I2C_ACTION_SEND_STOP: drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN; @@ -383,6 +525,15 @@ mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data) drv_data->block = 0; wake_up(&drv_data->waitq); break; + + case MV64XXX_I2C_ACTION_OFFLOAD_SEND_STOP: + mv64xxx_i2c_update_offload_data(drv_data); + writel(0, drv_data->reg_base + MV64XXX_I2C_REG_BRIDGE_CONTROL); + writel(0, drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE); + drv_data->block = 0; + wake_up(&drv_data->waitq); + break; } } @@ -395,6 +546,21 @@ mv64xxx_i2c_intr(int irq, void *dev_id) irqreturn_t rc = IRQ_NONE; spin_lock_irqsave(&drv_data->lock, flags); + + if (drv_data->offload_enabled) { + while (readl(drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_INTR_CAUSE)) { + int reg_status = readl(drv_data->reg_base + + MV64XXX_I2C_REG_BRIDGE_STATUS); + if (reg_status & MV64XXX_I2C_BRIDGE_STATUS_ERROR) + status = MV64XXX_I2C_STATUS_OFFLOAD_ERROR; + else + status = MV64XXX_I2C_STATUS_OFFLOAD_OK; + mv64xxx_i2c_fsm(drv_data, status); + mv64xxx_i2c_do_action(drv_data); + rc = IRQ_HANDLED; + } + } while (readl(drv_data->reg_base + drv_data->reg_offsets.control) & MV64XXX_I2C_REG_CONTROL_IFLG) { status = readl(drv_data->reg_base + drv_data->reg_offsets.status); @@ -459,11 +625,15 @@ mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg, unsigned long flags; spin_lock_irqsave(&drv_data->lock, flags); - mv64xxx_i2c_prepare_for_io(drv_data, msg); - - drv_data->action = MV64XXX_I2C_ACTION_SEND_START; - drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; + if (drv_data->offload_enabled) { + drv_data->action = MV64XXX_I2C_ACTION_OFFLOAD_SEND_START; + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; + } else { + mv64xxx_i2c_prepare_for_io(drv_data, msg); + drv_data->action = MV64XXX_I2C_ACTION_SEND_START; + drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_START_COND; + } drv_data->send_stop = is_last; drv_data->block = 1; mv64xxx_i2c_do_action(drv_data); @@ -521,11 +691,13 @@ static const struct i2c_algorithm mv64xxx_i2c_algo = { static const struct of_device_id mv64xxx_i2c_of_match_table[] = { { .compatible = "allwinner,sun4i-i2c", .data = &mv64xxx_i2c_regs_sun4i}, { .compatible = "marvell,mv64xxx-i2c", .data = &mv64xxx_i2c_regs_mv64xxx}, + { .compatible = "marvell,mv78230-i2c", .data = &mv64xxx_i2c_regs_mv64xxx}, {} }; MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table); #ifdef CONFIG_OF +#ifdef CONFIG_HAVE_CLK static int mv64xxx_calc_freq(const int tclk, const int n, const int m) { @@ -555,16 +727,12 @@ mv64xxx_find_baud_factors(const u32 req_freq, const u32 tclk, u32 *best_n, return false; return true; } +#endif /* CONFIG_HAVE_CLK */ static int mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, struct device *dev) { - const struct of_device_id *device; - struct device_node *np = dev->of_node; - u32 bus_freq, tclk; - int rc = 0; - /* CLK is mandatory when using DT to describe the i2c bus. We * need to know tclk in order to calculate bus clock * factors. @@ -573,6 +741,11 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, /* Have OF but no CLK */ return -ENODEV; #else + const struct of_device_id *device; + struct device_node *np = dev->of_node; + u32 bus_freq, tclk; + int rc = 0; + if (IS_ERR(drv_data->clk)) { rc = -ENODEV; goto out; @@ -601,6 +774,15 @@ mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data, memcpy(&drv_data->reg_offsets, device->data, sizeof(drv_data->reg_offsets)); + /* + * For controllers embedded in new SoCs activate the + * Transaction Generator support and the errata fix. + */ + if (of_device_is_compatible(np, "marvell,mv78230-i2c")) { + drv_data->offload_enabled = true; + drv_data->errata_delay = true; + } + out: return rc; #endif @@ -618,7 +800,7 @@ static int mv64xxx_i2c_probe(struct platform_device *pd) { struct mv64xxx_i2c_data *drv_data; - struct mv64xxx_i2c_pdata *pdata = pd->dev.platform_data; + struct mv64xxx_i2c_pdata *pdata = dev_get_platdata(&pd->dev); struct resource *r; int rc; @@ -654,6 +836,7 @@ mv64xxx_i2c_probe(struct platform_device *pd) drv_data->freq_n = pdata->freq_n; drv_data->irq = platform_get_irq(pd, 0); drv_data->adapter.timeout = msecs_to_jiffies(pdata->timeout); + drv_data->offload_enabled = false; memcpy(&drv_data->reg_offsets, &mv64xxx_i2c_regs_mv64xxx, sizeof(drv_data->reg_offsets)); } else if (pd->dev.of_node) { rc = mv64xxx_of_config(drv_data, &pd->dev); @@ -689,8 +872,6 @@ mv64xxx_i2c_probe(struct platform_device *pd) goto exit_free_irq; } - of_i2c_register_devices(&drv_data->adapter); - return 0; exit_free_irq: |