[PATCH u-boot 5/5] aspeed: I2C driver.

Maxim Sloyko maxims at google.com
Thu Nov 24 06:15:35 AEDT 2016


All comments will be addressed for the next version.

On Wed, Nov 23, 2016 at 8:24 AM, Simon Glass <sjg at chromium.org> wrote:
> [resend from correct address]
>
> On 23 November 2016 at 09:13, Simon Glass <sjg at google.com> wrote:
>> Hi Maxim,
>>
>> On 22 November 2016 at 16:56,  <maxims at google.com> wrote:
>>> From: Maxim Sloyko <maxims at google.com>
>>>
>>> The driver is very limited: only single master mode is supported
>>> and only byte-by-byte synchronous reads and writes are supported,
>>> no Pool Buffers or DMA.
>>
>> Please add that into the Kconfig help too.

Done.

>>
>>>
>>> Signed-off-by: Maxim Sloyko <maxims at google.com>
>>> ---
>>>  drivers/i2c/Kconfig   |   7 ++
>>>  drivers/i2c/Makefile  |   1 +
>>>  drivers/i2c/ast_i2c.c | 305 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>>  drivers/i2c/ast_i2c.h | 143 +++++++++++++++++++++++
>>>  4 files changed, 456 insertions(+)
>>>  create mode 100644 drivers/i2c/ast_i2c.c
>>>  create mode 100644 drivers/i2c/ast_i2c.h
>>>
>>> diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
>>> index 6e22bba..720c475 100644
>>> --- a/drivers/i2c/Kconfig
>>> +++ b/drivers/i2c/Kconfig
>>> @@ -90,6 +90,13 @@ config SYS_I2C_DW_ENABLE_STATUS_UNSUPPORTED
>>>           enable status register. This config option can be enabled in such
>>>           cases.
>>>
>>> +config SYS_I2C_AST
>>> +       bool "Aspeed I2C Controller"
>>> +       depends on DM_I2C
>>> +       help
>>> +         Say yes here to select Aspeed I2C Host Controller. The driver
>>> +         supports AST2500 and AST2400 controllers.
>>> +
>>>  config SYS_I2C_INTEL
>>>         bool "Intel I2C/SMBUS driver"
>>>         depends on DM_I2C
>>> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
>>> index 167424d..89e046e 100644
>>> --- a/drivers/i2c/Makefile
>>> +++ b/drivers/i2c/Makefile
>>> @@ -16,6 +16,7 @@ obj-$(CONFIG_PCA9564_I2C) += pca9564_i2c.o
>>>  obj-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
>>>  obj-$(CONFIG_SH_SH7734_I2C) += sh_sh7734_i2c.o
>>>  obj-$(CONFIG_SYS_I2C) += i2c_core.o
>>> +obj-$(CONFIG_SYS_I2C_AST) += ast_i2c.o
>>>  obj-$(CONFIG_SYS_I2C_CADENCE) += i2c-cdns.o
>>>  obj-$(CONFIG_SYS_I2C_DAVINCI) += davinci_i2c.o
>>>  obj-$(CONFIG_SYS_I2C_DW) += designware_i2c.o
>>> diff --git a/drivers/i2c/ast_i2c.c b/drivers/i2c/ast_i2c.c
>>> new file mode 100644
>>> index 0000000..f2c132e
>>> --- /dev/null
>>> +++ b/drivers/i2c/ast_i2c.c
>>> @@ -0,0 +1,305 @@
>>> +/*
>>> + * Copyright (C) 2012-2020  ASPEED Technology Inc.
>>> + * Copyright 2016 IBM Corporation
>>> + * Copyright 2016 Google, Inc.
>>> + *
>>> + * SPDX-License-Identifier:    GPL-2.0+
>>> + */
>>> +
>>> +#include <common.h>
>>> +#include <dm.h>
>>> +#include <fdtdec.h>
>>> +#include <i2c.h>
>>> +
>>> +#include <asm/arch/ast_scu.h>
>>> +#include <asm/arch/regs-scu.h>
>>> +#include <asm/io.h>
>>> +
>>> +#include "ast_i2c.h"
>>> +
>>> +#define I2C_TIMEOUT_US (100000)
>>> +#define I2C_SLEEP_STEP (20)
>>
>> I2C_SLEEP_STEP_US
>>
>>> +#define EI2C_TIMEOUT (1001)
>>
>> EI2C_TIMEOUT_US
>>
>> Please drop the () on those
>>
>>> +
>>> +DECLARE_GLOBAL_DATA_PTR;
>>> +
>>> +struct ast_i2c {
>>
>> Please add a struct comment with member info.
>>
>>> +       u32 id;
>>> +       struct ast_i2c_regs *regs;
>>> +       int speed;
>>> +};
>>> +
>>> +static u32 get_clk_reg_val(u32 divider_ratio)
>>
>> Function comment. Consider returning ulong.

It calculates register value, so I think it makes sense for it to be u32.

>>
>>> +{
>>> +       unsigned int inc = 0, div;
>>> +       u32 scl_low, scl_high, data;
>>> +
>>> +       for (div = 0; divider_ratio >= 16; div++) {
>>> +               inc |= (divider_ratio & 1);
>>> +               divider_ratio >>= 1;
>>> +       }
>>> +       divider_ratio += inc;
>>> +       scl_low = (divider_ratio >> 1) - 1;
>>> +       scl_high = divider_ratio - scl_low - 2;
>>> +       data = 0x77700300 | (scl_high << 16) | (scl_low << 12) | div;
>>
>> blank link here. What is the magic 0x77700300 for? Should either have
>> a comment or a #define
>>
>>> +       return data;
>>> +}
>>> +
>>> +static inline void ast_i2c_clear_interrupts(struct ast_i2c_regs *i2c_base)
>>> +{
>>> +       writel(~0, &i2c_base->isr);
>>> +}
>>> +
>>> +static void ast_i2c_init_bus(struct ast_i2c *i2c_bus)
>>> +{
>>> +       /* Reset device */
>>> +       writel(0, &i2c_bus->regs->fcr);
>>> +       /* Enable Master Mode. Assuming single-master. */
>>
>> nit: Please avoid '.' at end of comments
>>
>>> +       debug("Enable Master for %p\n", i2c_bus->regs);
>>> +       writel(AST_I2CD_MASTER_EN
>>> +              | AST_I2CD_M_SDA_LOCK_EN
>>> +              | AST_I2CD_MULTI_MASTER_DIS | AST_I2CD_M_SCL_DRIVE_EN,
>>> +              &i2c_bus->regs->fcr);
>>> +       debug("FCR: %p\n", &i2c_bus->regs->fcr);
>>> +       /* Enable Interrupts */
>>> +       writel(AST_I2CD_INTR_TX_ACK
>>> +              | AST_I2CD_INTR_TX_NAK
>>> +              | AST_I2CD_INTR_RX_DONE
>>> +              | AST_I2CD_INTR_BUS_RECOVER_DONE
>>> +              | AST_I2CD_INTR_NORMAL_STOP
>>> +              | AST_I2CD_INTR_ABNORMAL, &i2c_bus->regs->icr);
>>> +}
>>> +
>>> +static int ast_i2c_probe(struct udevice *dev)
>>> +{
>>> +       struct ast_i2c *i2c_bus = dev_get_priv(dev);
>>> +
>>> +       debug("Enabling I2C%u\n", dev->seq);
>>> +       ast_scu_enable_i2c(dev->seq);
>>> +
>>> +       i2c_bus->id = dev->seq;
>>> +       struct ast_i2c_regs *i2c_base =
>>> +           (struct ast_i2c_regs *)dev_get_addr(dev);
>>
>> Can you use dev_get_addr_ptr()? Need to check for NULL and return
>> -EINVAL. Also, reading the device tree should really be in the
>> ofdata_to_platdata() method, not probe().
>>
>>> +       i2c_bus->regs = i2c_base;
>>> +
>>> +       ast_i2c_init_bus(i2c_bus);
>>> +       return 0;
>>> +}
>>> +
>>> +static inline int ast_i2c_wait_isr(struct ast_i2c_regs *i2c_base, u32 flag)
>>> +{
>>> +       int timeout = I2C_TIMEOUT_US;
>>
>> blank line here
>>
>>> +       while (!(readl(&i2c_base->isr) & flag) && timeout > 0) {
>>> +               udelay(I2C_SLEEP_STEP);
>>> +               timeout -= I2C_SLEEP_STEP;
>>> +       }
>>
>>
>>> +
>>> +       ast_i2c_clear_interrupts(i2c_base);
>>> +       if (timeout <= 0)
>>> +               return -EI2C_TIMEOUT;
>>
>> return -ETIMEDOUT
>>
>>> +       return 0;
>>> +}
>>> +
>>> +static inline int ast_i2c_send_stop(struct ast_i2c_regs *i2c_base)
>>> +{
>>> +       writel(AST_I2CD_M_STOP_CMD, &i2c_base->csr);
>>
>> blank line (please do this before each return)
>>
>>> +       return ast_i2c_wait_isr(i2c_base, AST_I2CD_INTR_NORMAL_STOP);
>>> +}
>>> +
>>> +static inline int ast_i2c_wait_tx(struct ast_i2c_regs *i2c_base)
>>> +{
>>> +       int timeout = I2C_TIMEOUT_US;
>>> +       u32 flag = AST_I2CD_INTR_TX_ACK | AST_I2CD_INTR_TX_NAK;
>>> +       u32 status = readl(&i2c_base->isr) & flag;
>>
>> blank line (please do this after all decl blocks)
>>
>>> +       while (!status && timeout > 0) {
>>> +               status = readl(&i2c_base->isr) & flag;
>>> +               udelay(I2C_SLEEP_STEP);
>>> +               timeout -= I2C_SLEEP_STEP;
>>> +       }
>>> +
>>> +       int ret = 0;
>>
>> Move this to top of function. Declarations should all be at the start
>> of the block.
>>
>>> +       if (status == AST_I2CD_INTR_TX_NAK)
>>> +               ret = -EREMOTEIO;
>>> +
>>> +       if (timeout <= 0)
>>> +               ret = -EI2C_TIMEOUT;
>>> +
>>> +       ast_i2c_clear_interrupts(i2c_base);
>>> +       return ret;
>>> +}
>>> +
>>> +static inline int ast_i2c_start_txn(struct ast_i2c_regs *i2c_base, u8 devaddr)
>>
>> Why inline? The compiler will do that anyway so I think you can drop
>> it. Also please use int or uint for devaddr - particularly on ARM it
>> isn't good to have non-register-sized parameters and return values.
>>
>>> +{
>>> +       /* Start and Send Device Address */
>>> +       writel(devaddr, &i2c_base->trbbr);
>>> +       writel(AST_I2CD_M_START_CMD | AST_I2CD_M_TX_CMD, &i2c_base->csr);
>>> +       return ast_i2c_wait_tx(i2c_base);
>>> +}
>>> +
>>> +static int ast_i2c_read_data(struct ast_i2c *i2c_bus, u8 chip_addr, u8 *buffer,
>>> +                            size_t len, bool send_stop)
>>> +{
>>> +       struct ast_i2c_regs *i2c_base = i2c_bus->regs;
>>> +
>>> +       int i2c_error =
>>> +           ast_i2c_start_txn(i2c_base, (chip_addr << 1) | I2C_M_RD);
>>> +       if (i2c_error < 0)
>>> +               return i2c_error;
>>> +
>>> +       u32 i2c_cmd = AST_I2CD_M_RX_CMD;
>>> +       for (; len > 0; len--, buffer++) {
>>> +               if (len == 1)
>>> +                       i2c_cmd |= AST_I2CD_M_S_RX_CMD_LAST;
>>> +               writel(i2c_cmd, &i2c_base->csr);
>>> +               i2c_error = ast_i2c_wait_isr(i2c_base, AST_I2CD_INTR_RX_DONE);
>>> +               if (i2c_error < 0)
>>> +                       return i2c_error;
>>> +               *buffer = AST_I2CD_RX_DATA_BUF_GET(readl(&i2c_base->trbbr));
>>
>> Instead of AST_I2CD_RX_DATA_BUF_GET(), please define something like
>> AST_I2CD_RX_DATA_SHIFT and _MASK and use then here.
>>
>> #define AST_I2CD_RX_DATA_SHIFT  8
>> #define AST_I2CD_RX_DATA_MASK  (0xff << AST_I2CD_RX_DATA_SHIFT)
>>
>>
>>> +       }
>>> +       ast_i2c_clear_interrupts(i2c_base);
>>> +
>>> +       if (send_stop)
>>> +               return ast_i2c_send_stop(i2c_base);
>>> +
>>> +       return 0;
>>> +}
>>> +
>>> +static int ast_i2c_write_data(struct ast_i2c *i2c_bus, u8 chip_addr, u8
>>> +                             *buffer, size_t len, bool send_stop)
>>> +{
>>> +       struct ast_i2c_regs *i2c_base = i2c_bus->regs;
>>> +
>>> +       int i2c_error = ast_i2c_start_txn(i2c_base, (chip_addr << 1));
>>> +       if (i2c_error < 0)
>>> +               return i2c_error;
>>> +
>>> +       for (; len > 0; len--, buffer++) {
>>> +               writel(*buffer, &i2c_base->trbbr);
>>> +               writel(AST_I2CD_M_TX_CMD, &i2c_base->csr);
>>> +               i2c_error = ast_i2c_wait_tx(i2c_base);
>>> +               if (i2c_error < 0)
>>> +                       return i2c_error;
>>> +       }
>>> +
>>> +       if (send_stop)
>>> +               return ast_i2c_send_stop(i2c_base);
>>> +
>>> +       return 0;
>>> +}
>>> +
>>> +static int ast_i2c_deblock(struct udevice *dev)
>>> +{
>>> +       struct ast_i2c *i2c_bus = dev_get_priv(dev);
>>> +       struct ast_i2c_regs *i2c_base = i2c_bus->regs;
>>> +
>>> +       u32 csr = readl(&i2c_base->csr);
>>> +
>>> +       int deblock_error = 0;
>>
>> Just 'ret' is good enough.
>>
>>> +       bool sda_high = csr & AST_I2CD_SDA_LINE_STS;
>>> +       bool scl_high = csr & AST_I2CD_SCL_LINE_STS;
>>> +       if (sda_high && scl_high) {
>>> +               /* Bus is idle, no deblocking needed. */
>>> +               return 0;
>>> +       } else if (sda_high) {
>>> +               /* Send stop command */
>>> +               debug("Unterminated TXN in (%x), sending stop\n", csr);
>>> +               deblock_error = ast_i2c_send_stop(i2c_base);
>>> +       } else if (scl_high) {
>>> +               /* Possibly stuck slave */
>>> +               debug("Bus stuck (%x), attempting recovery\n", csr);
>>> +               writel(AST_I2CD_BUS_RECOVER_CMD, &i2c_base->csr);
>>> +               deblock_error = ast_i2c_wait_isr(
>>> +                       i2c_base, AST_I2CD_INTR_BUS_RECOVER_DONE);
>>> +       } else {
>>> +               /* Just try to reinit the device. */
>>> +               ast_i2c_init_bus(i2c_bus);
>>> +       }
>>> +
>>> +       return deblock_error;
>>> +}
>>> +
>>> +static int ast_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)
>>> +{
>>> +       struct ast_i2c *i2c_bus = dev_get_priv(dev);
>>> +       int ret;
>>> +
>>> +       (void)ast_i2c_deblock(dev);
>>> +       debug("i2c_xfer: %d messages\n", nmsgs);
>>> +       for (; nmsgs > 0; nmsgs--, msg++) {
>>> +               if (msg->flags & I2C_M_RD) {
>>> +                       debug("i2c_read: chip=0x%x, len=0x%x, flags=0x%x\n",
>>> +                             msg->addr, msg->len, msg->flags);
>>> +                       ret =
>>
>> Can you break the line in the parameters instead of at '=' ?
>>
>>> +                           ast_i2c_read_data(i2c_bus, msg->addr, msg->buf,
>>> +                                               msg->len, (nmsgs == 1));
>>> +               } else {
>>> +                       debug("i2c_write: chip=0x%x, len=0x%x, flags=0x%x\n",
>>> +                             msg->addr, msg->len, msg->flags);
>>> +                       ret =
>>> +                           ast_i2c_write_data(i2c_bus, msg->addr, msg->buf,
>>> +                                                msg->len, (nmsgs == 1));
>>> +               }
>>> +               if (ret) {
>>> +                       debug("%s: error (%d)\n", __func__, ret);
>>> +                       return -EREMOTEIO;
>>> +               }
>>> +       }
>>> +
>>> +       return 0;
>>> +}
>>> +
>>> +static int ast_i2c_set_speed(struct udevice *dev, unsigned int speed)
>>> +{
>>> +       debug("Setting speed ofr I2C%d to <%u>\n", dev->seq, speed);
>>> +       if (!speed) {
>>> +               debug("No valid speed specified.\n");
>>
>> Drop '.'
>>
>>> +               return -EINVAL;
>>> +       }
>>> +       struct ast_i2c *i2c_bus = dev_get_priv(dev);
>>> +
>>> +       i2c_bus->speed = speed;
>>> +       /* TODO: get this from device tree */
>>> +       u32 pclk = ast_get_apbclk();
>>> +       u32 divider = pclk / speed;
>>> +
>>> +       struct ast_i2c_regs *i2c_base = i2c_bus->regs;
>>> +       if (speed > 400000) {
>>> +               debug("Enabling High Speed\n");
>>> +               setbits_le32(&i2c_base->fcr, AST_I2CD_M_HIGH_SPEED_EN
>>> +                            | AST_I2CD_M_SDA_DRIVE_1T_EN
>>> +                            | AST_I2CD_SDA_DRIVE_1T_EN);
>>> +               writel(0x3, &i2c_base->cactcr2);
>>> +               writel(get_clk_reg_val(divider), &i2c_base->cactcr1);
>>> +       } else {
>>> +               debug("Enabling Normal Speed\n");
>>> +               writel(get_clk_reg_val(divider), &i2c_base->cactcr1);
>>> +               writel(AST_NO_TIMEOUT_CTRL, &i2c_base->cactcr2);
>>> +       }
>>> +
>>> +       ast_i2c_clear_interrupts(i2c_base);
>>> +       return 0;
>>> +}
>>> +
>>> +static const struct dm_i2c_ops ast_i2c_ops = {
>>> +       .xfer = ast_i2c_xfer,
>>> +       .set_bus_speed = ast_i2c_set_speed,
>>> +       .deblock = ast_i2c_deblock,
>>> +};
>>> +
>>> +static const struct udevice_id ast_i2c_ids[] = {
>>> +       {.compatible = "aspeed,ast2400-i2c-controller",},
>>> +       {.compatible = "aspeed,ast2400-i2c-bus",},
>>> +       {},
>>> +};
>>> +
>>> +/* Tell GNU Indent to keep this as is: */
>>> +/* *INDENT-OFF* */
>>> +U_BOOT_DRIVER(i2c_aspeed) = {
>>> +       .name = "i2c_aspeed",
>>> +       .id = UCLASS_I2C,
>>> +       .of_match = ast_i2c_ids,
>>> +       .probe = ast_i2c_probe,
>>> +       .priv_auto_alloc_size = sizeof(struct ast_i2c),
>>> +       .ops = &ast_i2c_ops,
>>> +};
>>> +/* *INDENT-ON* */
>>> diff --git a/drivers/i2c/ast_i2c.h b/drivers/i2c/ast_i2c.h
>>> new file mode 100644
>>> index 0000000..8926fd2
>>> --- /dev/null
>>> +++ b/drivers/i2c/ast_i2c.h
>>> @@ -0,0 +1,143 @@
>>> +/*
>>> + * Copyright (C) 2012-2020  ASPEED Technology Inc.
>>> + * Copyright 2016 IBM Corporation
>>> + * Copyright 2016 Google, Inc.
>>> + *
>>> + * SPDX-License-Identifier:    GPL-2.0+
>>> + */
>>> +#ifndef __AST_I2C_H_
>>> +#define __AST_I2C_H_
>>> +
>>> +struct ast_i2c_regs {
>>> +       uint32_t fcr;
>>> +       uint32_t cactcr1;
>>> +       uint32_t cactcr2;
>>> +       uint32_t icr;
>>> +       uint32_t isr;
>>> +       uint32_t csr;
>>> +       uint32_t sdar;
>>> +       uint32_t pbcr;
>>> +       uint32_t trbbr;
>>> +#ifdef CONFIG_TARGET_AST_G5
>>> +       uint32_t dma_mbar;
>>> +       uint32_t dma_tlr;
>>> +#endif
>>> +};
>>> +
>>> +/* Device Register Definition */
>>> +/* 0x00 : I2CD Function Control Register  */
>>> +#define AST_I2CD_BUFF_SEL_MASK                         (0x7 << 20)
>>
>> It's fine to have the AST_I2CD_ prefix if you want it. But it does
>> make things longer, and this header will only be included in one file.
>> So feel free to prune to AST_ if you like.
>>
>>> +#define AST_I2CD_BUFF_SEL(x)                           (x << 20)
>>> +#define AST_I2CD_M_SDA_LOCK_EN                 (0x1 << 16)
>>> +#define AST_I2CD_MULTI_MASTER_DIS                      (0x1 << 15)
>>> +#define AST_I2CD_M_SCL_DRIVE_EN                (0x1 << 14)
>>> +#define AST_I2CD_MSB_STS                                       (0x1 << 9)
>>> +#define AST_I2CD_SDA_DRIVE_1T_EN                       (0x1 << 8)
>>> +#define AST_I2CD_M_SDA_DRIVE_1T_EN             (0x1 << 7)
>>> +#define AST_I2CD_M_HIGH_SPEED_EN               (0x1 << 6)
>>> +#define AST_I2CD_DEF_ADDR_EN                           (0x1 << 5)
>>> +#define AST_I2CD_DEF_ALERT_EN                          (0x1 << 4)
>>> +#define AST_I2CD_DEF_ARP_EN                                    (0x1 << 3)
>>> +#define AST_I2CD_DEF_GCALL_EN                          (0x1 << 2)
>>> +#define AST_I2CD_SLAVE_EN                                      (0x1 << 1)
>>> +#define AST_I2CD_MASTER_EN                                     (0x1)
>>
>> Avoid brackets around simple constants
>>
>>> +
>>> +/* 0x04 : I2CD Clock and AC Timing Control Register #1 */
>>> +#define AST_I2CD_tBUF                                          (0x1 << 28)
>>> +#define AST_I2CD_tHDSTA                                                (0x1 << 24)
>>> +#define AST_I2CD_tACST                                         (0x1 << 20)
>>> +#define AST_I2CD_tCKHIGH                                       (0x1 << 16)
>>> +#define AST_I2CD_tCKLOW                                                (0x1 << 12)
>>> +#define AST_I2CD_tHDDAT                                                (0x1 << 10)
>>> +#define AST_I2CD_CLK_TO_BASE_DIV                       (0x1 << 8)
>>> +#define AST_I2CD_CLK_BASE_DIV                          (0x1)
>>> +
>>> +/* 0x08 : I2CD Clock and AC Timing Control Register #2 */
>>> +#define AST_I2CD_tTIMEOUT                                      (0x1)
>>> +#define AST_NO_TIMEOUT_CTRL                                    0x0
>>> +
>>> +/* 0x0c : I2CD Interrupt Control Register &
>>> + * 0x10 : I2CD Interrupt Status Register
>>> + *
>>> + * These share bit definitions, so use the same values for the enable &
>>> + * status bits.
>>> + */
>>> +#define AST_I2CD_INTR_SDA_DL_TIMEOUT                   (0x1 << 14)
>>> +#define AST_I2CD_INTR_BUS_RECOVER_DONE                 (0x1 << 13)
>>> +#define AST_I2CD_INTR_SMBUS_ALERT                      (0x1 << 12)
>>> +#define AST_I2CD_INTR_SMBUS_ARP_ADDR                   (0x1 << 11)
>>> +#define AST_I2CD_INTR_SMBUS_DEV_ALERT_ADDR             (0x1 << 10)
>>> +#define AST_I2CD_INTR_SMBUS_DEF_ADDR                   (0x1 << 9)
>>> +#define AST_I2CD_INTR_GCALL_ADDR                       (0x1 << 8)
>>> +#define AST_I2CD_INTR_SLAVE_MATCH                      (0x1 << 7)
>>> +#define AST_I2CD_INTR_SCL_TIMEOUT                      (0x1 << 6)
>>> +#define AST_I2CD_INTR_ABNORMAL                         (0x1 << 5)
>>> +#define AST_I2CD_INTR_NORMAL_STOP                      (0x1 << 4)
>>> +#define AST_I2CD_INTR_ARBIT_LOSS                       (0x1 << 3)
>>> +#define AST_I2CD_INTR_RX_DONE                          (0x1 << 2)
>>> +#define AST_I2CD_INTR_TX_NAK                           (0x1 << 1)
>>> +#define AST_I2CD_INTR_TX_ACK                           (0x1 << 0)
>>> +
>>> +/* 0x14 : I2CD Command/Status Register   */
>>> +#define AST_I2CD_SDA_OE                                        (0x1 << 28)
>>> +#define AST_I2CD_SDA_O                                 (0x1 << 27)
>>> +#define AST_I2CD_SCL_OE                                        (0x1 << 26)
>>> +#define AST_I2CD_SCL_O                                 (0x1 << 25)
>>> +#define AST_I2CD_TX_TIMING                             (0x1 << 24)
>>> +#define AST_I2CD_TX_STATUS                             (0x1 << 23)
>>> +
>>> +/* Tx State Machine */
>>> +#define AST_I2CD_IDLE                                  0x0
>>> +#define AST_I2CD_MACTIVE                               0x8
>>> +#define AST_I2CD_MSTART                                        0x9
>>> +#define AST_I2CD_MSTARTR                               0xa
>>> +#define AST_I2CD_MSTOP                                 0xb
>>> +#define AST_I2CD_MTXD                                  0xc
>>> +#define AST_I2CD_MRXACK                                        0xd
>>> +#define AST_I2CD_MRXD                                  0xe
>>> +#define AST_I2CD_MTXACK                                0xf
>>> +#define AST_I2CD_SWAIT                                 0x1
>>> +#define AST_I2CD_SRXD                                  0x4
>>> +#define AST_I2CD_STXACK                                0x5
>>> +#define AST_I2CD_STXD                                  0x6
>>> +#define AST_I2CD_SRXACK                                0x7
>>> +#define AST_I2CD_RECOVER                               0x3
>>> +
>>> +#define AST_I2CD_SCL_LINE_STS                          (0x1 << 18)
>>> +#define AST_I2CD_SDA_LINE_STS                          (0x1 << 17)
>>> +#define AST_I2CD_BUS_BUSY_STS                          (0x1 << 16)
>>> +#define AST_I2CD_SDA_OE_OUT_DIR                                (0x1 << 15)
>>> +#define AST_I2CD_SDA_O_OUT_DIR                         (0x1 << 14)
>>> +#define AST_I2CD_SCL_OE_OUT_DIR                                (0x1 << 13)
>>> +#define AST_I2CD_SCL_O_OUT_DIR                         (0x1 << 12)
>>> +#define AST_I2CD_BUS_RECOVER_CMD                       (0x1 << 11)
>>> +#define AST_I2CD_S_ALT_EN                              (0x1 << 10)
>>> +#define AST_I2CD_RX_DMA_ENABLE                         (0x1 << 9)
>>> +#define AST_I2CD_TX_DMA_ENABLE                         (0x1 << 8)
>>> +
>>> +/* Command Bit */
>>> +#define AST_I2CD_RX_BUFF_ENABLE                                (0x1 << 7)
>>> +#define AST_I2CD_TX_BUFF_ENABLE                                (0x1 << 6)
>>> +#define AST_I2CD_M_STOP_CMD                                    (0x1 << 5)
>>> +#define AST_I2CD_M_S_RX_CMD_LAST                       (0x1 << 4)
>>> +#define AST_I2CD_M_RX_CMD                                      (0x1 << 3)
>>> +#define AST_I2CD_S_TX_CMD                                      (0x1 << 2)
>>> +#define AST_I2CD_M_TX_CMD                                      (0x1 << 1)
>>> +#define AST_I2CD_M_START_CMD                           (0x1)
>>> +
>>> +/* 0x18 : I2CD Slave Device Address Register   */
>>> +
>>> +/* 0x1C : I2CD Pool Buffer Control Register   */
>>> +#define AST_I2CD_RX_BUF_ADDR_GET(x)                    (((x) >> 24) & 0xff)
>>> +#define AST_I2CD_RX_BUF_END_ADDR_SET(x)                        ((x) << 16)
>>> +#define AST_I2CD_TX_DATA_BUF_END_SET(x)                        (((x) & 0xff) << 8)
>>> +#define AST_I2CD_RX_DATA_BUF_GET(x)                    (((x) >> 8) & 0xff)
>>> +#define AST_I2CD_BUF_BASE_ADDR_SET(x)                  ((x) & 0x3f)
>>
>> Just use simple shift and mask values, and put the logic in your C code.
>>
>>> +
>>> +/* 0x20 : I2CD Transmit/Receive Byte Buffer Register   */
>>> +#define AST_I2CD_GET_MODE(x)                           (((x) >> 8) & 0x1)
>>> +
>>> +#define AST_I2CD_RX_BYTE_BUFFER                                        (0xff << 8)
>>> +#define AST_I2CD_TX_BYTE_BUFFER                                        (0xff)
>>> +
>>> +#endif                         /* __AST_I2C_H_ */
>>> --
>>> 2.8.0.rc3.226.g39d4020
>>>
>>
>> Regards,
>> Simon



-- 
Maxim Sloyko


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