Latest AMDGPU NAVI cards have USB Type-C interface which can be accessed over I2C. The Type-C controller has integrated designware i2c which is exposed as a PCI device to the AMD platform. Also there exists couple of notable IP problems that are dealt as a workaround: - I2C transactions work on a polling mode as IP does not generate interrupt. - I2C reads commands are sent twice to address the IP issues. Reviewed-by: Shyam Sundar S K <Shyam-sundar.S-k@xxxxxxx> Co-developed-by: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@xxxxxxx> Signed-off-by: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@xxxxxxx> Signed-off-by: Sanket Goswami <Sanket.Goswami@xxxxxxx> --- drivers/i2c/busses/i2c-designware-common.c | 3 + drivers/i2c/busses/i2c-designware-core.h | 3 + drivers/i2c/busses/i2c-designware-master.c | 175 +++++++++++++++++++++ drivers/i2c/busses/i2c-designware-pcidrv.c | 56 +++++++ 4 files changed, 237 insertions(+) diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c index 3c19aada4b30..50883a70b482 100644 --- a/drivers/i2c/busses/i2c-designware-common.c +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -150,6 +150,9 @@ int i2c_dw_init_regmap(struct dw_i2c_dev *dev) reg = readl(dev->base + DW_IC_COMP_TYPE); i2c_dw_release_lock(dev); + if (dev->flags & AMD_NON_INTR_MODE) + map_cfg.max_register = AMD_UCSI_INTR_REG; + if (reg == swab32(DW_IC_COMP_TYPE_VALUE)) { map_cfg.reg_read = dw_reg_read_swab; map_cfg.reg_write = dw_reg_write_swab; diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 85307cfa7109..0cce4144b9ac 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -291,9 +291,12 @@ struct dw_i2c_dev { #define ACCESS_INTR_MASK BIT(0) #define ACCESS_NO_IRQ_SUSPEND BIT(1) +#define AMD_NON_INTR_MODE BIT(2) #define MODEL_MSCC_OCELOT BIT(8) #define MODEL_BAIKAL_BT1 BIT(9) #define MODEL_MASK GENMASK(11, 8) +#define AMD_UCSI_INTR_EN 0xD +#define AMD_UCSI_INTR_REG 0x474 int i2c_dw_init_regmap(struct dw_i2c_dev *dev); u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset); diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index d6425ad6e6a3..35c894a01381 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -22,6 +22,10 @@ #include <linux/reset.h> #include "i2c-designware-core.h" +#define AMD_TIMEOUT_MSEC_MIN 10000 +#define AMD_TIMEOUT_MSEC_MAX 11000 +#define AMD_FIFO_SIZE 0x20 +#define AMD_MASTERCFG_MASK GENMASK(15, 0) static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev) { @@ -33,6 +37,154 @@ static void i2c_dw_configure_fifo_master(struct dw_i2c_dev *dev) regmap_write(dev->map, DW_IC_CON, dev->master_cfg); } +static void i2c_dw_configure_bus(struct dw_i2c_dev *i2cd) +{ + int master_cfg; + u16 icon; + u32 reg; + + /* First disable the controller */ + __i2c_dw_disable_nowait(i2cd); + master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | DW_IC_CON_SPEED_STD; + + /* Clear all the interrupts */ + regmap_read(i2cd->map, DW_IC_CLR_INTR, ®); + regmap_write(i2cd->map, DW_IC_INTR_MASK, STATUS_IDLE); + + icon = master_cfg & AMD_MASTERCFG_MASK; + icon &= ~DW_IC_CON_10BITADDR_MASTER; + icon = icon | DW_IC_CON_SPEED_STD; + + /* Configure the master */ + regmap_write(i2cd->map, DW_IC_CON, icon); + /* Configure the FIFO */ + regmap_write(i2cd->map, DW_IC_TX_TL, AMD_FIFO_SIZE); + regmap_write(i2cd->map, DW_IC_RX_TL, AMD_FIFO_SIZE); + + /* Setup 100k Speed */ + regmap_write(i2cd->map, DW_IC_SS_SCL_HCNT, i2cd->ss_hcnt); + regmap_write(i2cd->map, DW_IC_SS_SCL_LCNT, i2cd->ss_lcnt); + regmap_write(i2cd->map, DW_IC_TAR, 0x08); + + /* Now enable the controller */ + __i2c_dw_enable(i2cd); +} + +static int i2c_dw_check_stopbit(struct dw_i2c_dev *i2cd) +{ + u32 val; + int ret; + + ret = regmap_read_poll_timeout(i2cd->map, DW_IC_INTR_STAT, val, + !(val & DW_IC_INTR_STOP_DET), + 1100, 20000); + if (ret) { + dev_err(i2cd->dev, "i2c timeout error %d\n", ret); + return -ETIMEDOUT; + } + + regmap_read(i2cd->map, DW_IC_CLR_INTR, &val); + if (val & DW_IC_INTR_STOP_DET) + return -ETIMEDOUT; + + return 0; +} + +static int i2c_dw_status(struct dw_i2c_dev *i2cd) +{ + int status; + + status = i2c_dw_wait_bus_not_busy(i2cd); + if (status) + return -ETIMEDOUT; + + status = i2c_dw_check_stopbit(i2cd); + if (status) + return -ETIMEDOUT; + + return status; +} + +/* Initiate and continue master read/write transaction with polling + * based transfer routine and write messages into the tx buffer. + */ +static int amd_i2c_dw_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num_msgs) +{ + struct dw_i2c_dev *i2cd = i2c_get_adapdata(adap); + int msg_wrt_idx, msg_itr_lmt, buf_len, data_idx; + int cmd = 0, ret, status; + u8 *tx_buf; + u32 val; + + ret = i2c_dw_acquire_lock(i2cd); + if (ret) { + dev_err(i2cd->dev, "Failed to get bus ownership\n"); + return ret; + } + + i2c_dw_configure_bus(i2cd); + + /* Initiate messages read/write transaction */ + for (msg_wrt_idx = 0; msg_wrt_idx < num_msgs; msg_wrt_idx++) { + tx_buf = msgs[msg_wrt_idx].buf; + buf_len = msgs[msg_wrt_idx].len; + + if (!(msgs[msg_wrt_idx].flags & I2C_M_RD)) + regmap_write(i2cd->map, DW_IC_TX_TL, buf_len - 1); + + /* Initiate the i2c read/write transition of buffer length, + * and poll for bus busy status. For the last message transfer, + * update the command with stopbit enable. + */ + for (msg_itr_lmt = buf_len; msg_itr_lmt > 0; msg_itr_lmt--) { + if (msg_wrt_idx == num_msgs - 1 && msg_itr_lmt == 1) + cmd |= BIT(9); + + if (msgs[msg_wrt_idx].flags & I2C_M_RD) { + /* Due to hardware bug, need to write command two times. */ + regmap_write(i2cd->map, DW_IC_DATA_CMD, 0x100); + regmap_write(i2cd->map, DW_IC_DATA_CMD, 0x100 | cmd); + if (cmd) { + regmap_write(i2cd->map, DW_IC_TX_TL, 2 * (buf_len - 1)); + regmap_write(i2cd->map, DW_IC_RX_TL, 2 * (buf_len - 1)); + + /* Need to check the stop bit. However, it cannot be + * detected from the registers so we check it always + * when read/write the last byte. + */ + status = i2c_dw_status(i2cd); + if (status) { + ret = -ETIMEDOUT; + goto lock_release; + } + for (data_idx = 0; data_idx < buf_len; data_idx++) { + regmap_read(i2cd->map, DW_IC_DATA_CMD, &val); + tx_buf[data_idx] = val; + } + status = i2c_dw_check_stopbit(i2cd); + if (status) { + ret = -ETIMEDOUT; + goto lock_release; + } + } + } else { + regmap_write(i2cd->map, DW_IC_DATA_CMD, *tx_buf++ | cmd); + usleep_range(AMD_TIMEOUT_MSEC_MIN, AMD_TIMEOUT_MSEC_MAX); + } + } + status = i2c_dw_check_stopbit(i2cd); + if (status) { + ret = -ETIMEDOUT; + goto lock_release; + } + } + +lock_release: + i2c_dw_release_lock(i2cd); + + return ret; +} + static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev) { const char *mode_str, *fp_str = ""; @@ -208,6 +360,9 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev) if (dev->sda_hold_time) regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time); + /* Enable ucsi interrupt */ + if (dev->flags & AMD_NON_INTR_MODE) + regmap_write(dev->map, AMD_UCSI_INTR_REG, AMD_UCSI_INTR_EN); i2c_dw_configure_fifo_master(dev); i2c_dw_release_lock(dev); @@ -462,6 +617,9 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) pm_runtime_get_sync(dev->dev); + if (dev->flags & AMD_NON_INTR_MODE) + return amd_i2c_dw_master_xfer(adap, msgs, num); + if (dev_WARN_ONCE(dev->dev, dev->suspended, "Transfer while suspended\n")) { ret = -ESHUTDOWN; goto done_nolock; @@ -738,6 +896,19 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev) return 0; } +int amd_i2c_adap_quirk(struct dw_i2c_dev *amdev) +{ + struct i2c_adapter *amdap = &amdev->adapter; + int ret; + + if (!(amdev->flags & AMD_NON_INTR_MODE)) + return -ENODEV; + + return i2c_add_numbered_adapter(amdap); + + return ret; +} + int i2c_dw_probe_master(struct dw_i2c_dev *dev) { struct i2c_adapter *adap = &dev->adapter; @@ -774,6 +945,10 @@ int i2c_dw_probe_master(struct dw_i2c_dev *dev) adap->dev.parent = dev->dev; i2c_set_adapdata(adap, dev); + ret = amd_i2c_adap_quirk(dev); + if (ret != -ENODEV) + return ret; + if (dev->flags & ACCESS_NO_IRQ_SUSPEND) { irq_flags = IRQF_NO_SUSPEND; } else { diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c index 55c83a7a24f3..69ea6f206ab2 100644 --- a/drivers/i2c/busses/i2c-designware-pcidrv.c +++ b/drivers/i2c/busses/i2c-designware-pcidrv.c @@ -26,6 +26,7 @@ #include "i2c-designware-core.h" #define DRIVER_NAME "i2c-designware-pci" +#define AMD_CLK_RATE 100000 enum dw_pci_ctl_id_t { medfield, @@ -34,6 +35,7 @@ enum dw_pci_ctl_id_t { cherrytrail, haswell, elkhartlake, + navi_amd, }; struct dw_scl_sda_cfg { @@ -78,11 +80,23 @@ static struct dw_scl_sda_cfg hsw_config = { .sda_hold = 0x9, }; +/* NAVI-AMD HCNT/LCNT/SDA hold time */ +static struct dw_scl_sda_cfg navi_amd_config = { + .ss_hcnt = 0x1ae, + .ss_lcnt = 0x23a, + .sda_hold = 0x9, +}; + static u32 mfld_get_clk_rate_khz(struct dw_i2c_dev *dev) { return 25000; } +static u32 navi_amd_get_clk_rate_khz(struct dw_i2c_dev *dev) +{ + return AMD_CLK_RATE; +} + static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c) { struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev); @@ -104,6 +118,35 @@ static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c) return -ENODEV; } +static int i2c_dw_populate_client(struct dw_i2c_dev *i2cd) +{ + struct i2c_board_info *i2c_dw_ccgx_ucsi; + struct i2c_client *ccgx_client; + + i2c_dw_ccgx_ucsi = devm_kzalloc(i2cd->dev, sizeof(*i2c_dw_ccgx_ucsi), GFP_KERNEL); + if (!i2c_dw_ccgx_ucsi) + return -ENOMEM; + + strscpy(i2c_dw_ccgx_ucsi->type, "ccgx-ucsi", sizeof(i2c_dw_ccgx_ucsi->type)); + i2c_dw_ccgx_ucsi->addr = 0x08; + i2c_dw_ccgx_ucsi->irq = i2cd->irq; + + ccgx_client = i2c_new_client_device(&i2cd->adapter, i2c_dw_ccgx_ucsi); + if (!ccgx_client) + return -ENODEV; + + return 0; +} + +static int navi_amd_setup(struct pci_dev *pdev, struct dw_pci_controller *c) +{ + struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev); + + dev->flags |= AMD_NON_INTR_MODE; + dev->timings.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; + return 0; +} + static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c) { /* @@ -155,6 +198,12 @@ static struct dw_pci_controller dw_pci_controllers[] = { .bus_num = -1, .get_clk_rate_khz = ehl_get_clk_rate_khz, }, + [navi_amd] = { + .bus_num = -1, + .scl_sda_cfg = &navi_amd_config, + .setup = navi_amd_setup, + .get_clk_rate_khz = navi_amd_get_clk_rate_khz, + }, }; #ifdef CONFIG_PM @@ -274,6 +323,9 @@ static int i2c_dw_pci_probe(struct pci_dev *pdev, return r; } + if (dev->flags & AMD_NON_INTR_MODE) + i2c_dw_populate_client(dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, 1000); pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_put_autosuspend(&pdev->dev); @@ -337,6 +389,10 @@ static const struct pci_device_id i2_designware_pci_ids[] = { { PCI_VDEVICE(INTEL, 0x4bbe), elkhartlake }, { PCI_VDEVICE(INTEL, 0x4bbf), elkhartlake }, { PCI_VDEVICE(INTEL, 0x4bc0), elkhartlake }, + { PCI_VDEVICE(ATI, 0x7314), navi_amd }, + { PCI_VDEVICE(ATI, 0x73a4), navi_amd }, + { PCI_VDEVICE(ATI, 0x73e4), navi_amd }, + { PCI_VDEVICE(ATI, 0x73c4), navi_amd }, { 0,} }; MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids); -- 2.25.1