Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932145AbcDKP3X (ORCPT ); Mon, 11 Apr 2016 11:29:23 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:33127 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755325AbcDKP3T (ORCPT ); Mon, 11 Apr 2016 11:29:19 -0400 From: Jan Glauber To: Wolfram Sang Cc: linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, David Daney , Jan Glauber Subject: [PATCH v6 17/19] i2c: thunderx: Add i2c driver for ThunderX SOC Date: Mon, 11 Apr 2016 17:28:48 +0200 Message-Id: X-Mailer: git-send-email 1.9.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10076 Lines: 367 The ThunderX SOC uses the same i2c block as the Octeon SOC. The main difference is that on ThunderX the device is a PCI device so device probing is done via PCI, interrupts are MSIX and the clock is taken from device tree. Signed-off-by: Jan Glauber --- drivers/i2c/busses/Kconfig | 10 ++ drivers/i2c/busses/Makefile | 2 + drivers/i2c/busses/i2c-cavium.h | 17 ++- drivers/i2c/busses/i2c-thunderx-core.c | 269 +++++++++++++++++++++++++++++++++ 4 files changed, 295 insertions(+), 3 deletions(-) create mode 100644 drivers/i2c/busses/i2c-thunderx-core.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index faa8e68..92d23de 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -953,6 +953,16 @@ config I2C_OCTEON This driver can also be built as a module. If so, the module will be called i2c-octeon. +config I2C_THUNDERX + tristate "Cavium ThunderX I2C bus support" + depends on 64BIT && PCI && !CAVIUM_OCTEON_SOC + help + Say yes if you want to support the I2C serial bus on Cavium + ThunderX SOC. + + This driver can also be built as a module. If so, the module + will be called i2c-thunderx. + config I2C_XILINX tristate "Xilinx I2C Controller" depends on HAS_IOMEM diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 282f781..a32ff14 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -93,6 +93,8 @@ obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o obj-$(CONFIG_I2C_WMT) += i2c-wmt.o i2c-octeon-objs := i2c-cavium.o i2c-octeon-core.o obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o +i2c-thunderx-objs := i2c-cavium.o i2c-thunderx-core.o +obj-$(CONFIG_I2C_THUNDERX) += i2c-thunderx.o obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o obj-$(CONFIG_I2C_XLR) += i2c-xlr.o obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o diff --git a/drivers/i2c/busses/i2c-cavium.h b/drivers/i2c/busses/i2c-cavium.h index e17f2dc..d8d4e0b 100644 --- a/drivers/i2c/busses/i2c-cavium.h +++ b/drivers/i2c/busses/i2c-cavium.h @@ -8,9 +8,15 @@ #include /* Register offsets */ -#define SW_TWSI 0x00 -#define TWSI_INT 0x10 -#define SW_TWSI_EXT 0x18 +#if IS_ENABLED(CONFIG_I2C_THUNDERX) + #define SW_TWSI 0x1000 + #define TWSI_INT 0x1010 + #define SW_TWSI_EXT 0x1018 +#else + #define SW_TWSI 0x00 + #define TWSI_INT 0x10 + #define SW_TWSI_EXT 0x18 +#endif /* Controller command patterns */ #define SW_TWSI_V BIT_ULL(63) /* Valid bit */ @@ -92,6 +98,7 @@ struct octeon_i2c { wait_queue_head_t queue; struct i2c_adapter adap; + struct clk *clk; int irq; int hlc_irq; /* For cn7890 only */ u32 twsi_freq; @@ -107,6 +114,10 @@ struct octeon_i2c { void (*hlc_int_dis)(struct octeon_i2c *); atomic_t int_en_cnt; atomic_t hlc_int_en_cnt; + +#if IS_ENABLED(CONFIG_I2C_THUNDERX) + struct msix_entry i2c_msix; +#endif }; static inline void writeqflush(u64 val, void __iomem *addr) diff --git a/drivers/i2c/busses/i2c-thunderx-core.c b/drivers/i2c/busses/i2c-thunderx-core.c new file mode 100644 index 0000000..99006a4 --- /dev/null +++ b/drivers/i2c/busses/i2c-thunderx-core.c @@ -0,0 +1,269 @@ +/* + * Cavium ThunderX i2c driver. + * + * Copyright (C) 2015,2016 Cavium Inc. + * Authors: Fred Martin + * Jan Glauber + */ + +#include +#include +#include +#include +#include +#include +#include + +#include "i2c-cavium.h" + +#define DRV_NAME "i2c-thunderx" + +#define PCI_CFG_REG_BAR_NUM 0 +#define PCI_DEVICE_ID_THUNDER_TWSI 0xa012 + +#define TWSI_DFL_RATE 100000 +#define SYS_FREQ_DEFAULT 800000000 + +#define TWSI_INT_ENA_W1C 0x1028 +#define TWSI_INT_ENA_W1S 0x1030 + +/* + * Enable the CORE interrupt. + * The interrupt will be asserted when there is non-STAT_IDLE state in the + * SW_TWSI_EOP_TWSI_STAT register. + */ +static void thunder_i2c_int_enable(struct octeon_i2c *i2c) +{ + __raw_writeq(TWSI_INT_CORE_INT, i2c->twsi_base + TWSI_INT_ENA_W1S); + __raw_readq(i2c->twsi_base + TWSI_INT_ENA_W1S); +} + +/* + * Disable the CORE interrupt. + */ +static void thunder_i2c_int_disable(struct octeon_i2c *i2c) +{ + __raw_writeq(TWSI_INT_CORE_INT, i2c->twsi_base + TWSI_INT_ENA_W1C); + __raw_readq(i2c->twsi_base + TWSI_INT_ENA_W1C); +} + +static void thunder_i2c_hlc_int_enable(struct octeon_i2c *i2c) +{ + __raw_writeq(TWSI_INT_ST_INT | TWSI_INT_TS_INT, + i2c->twsi_base + TWSI_INT_ENA_W1S); + __raw_readq(i2c->twsi_base + TWSI_INT_ENA_W1S); +} + +static void thunder_i2c_hlc_int_disable(struct octeon_i2c *i2c) +{ + __raw_writeq(TWSI_INT_ST_INT | TWSI_INT_TS_INT, + i2c->twsi_base + TWSI_INT_ENA_W1C); + __raw_readq(i2c->twsi_base + TWSI_INT_ENA_W1C); +} + +static u32 thunderx_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL; +} + +static const struct i2c_algorithm thunderx_i2c_algo = { + .master_xfer = octeon_i2c_xfer, + .functionality = thunderx_i2c_functionality, +}; + +static struct i2c_adapter thunderx_i2c_ops = { + .owner = THIS_MODULE, + .name = "ThunderX adapter", + .algo = &thunderx_i2c_algo, +}; + +static void thunder_i2c_clock_enable(struct device *dev, struct octeon_i2c *i2c) +{ + int ret; + + i2c->clk = devm_clk_get(dev, NULL); + if (IS_ERR(i2c->clk)) { + i2c->clk = NULL; + goto skip; + } + + ret = clk_prepare_enable(i2c->clk); + if (ret) + goto skip; + i2c->sys_freq = clk_get_rate(i2c->clk); + +skip: + if (!i2c->sys_freq) + i2c->sys_freq = SYS_FREQ_DEFAULT; + + dev_info(dev, "Set system clock to %u\n", i2c->sys_freq); +} + +static void thunder_i2c_clock_disable(struct device *dev, struct clk *clk) +{ + if (!clk) + return; + clk_disable_unprepare(clk); + devm_clk_put(dev, clk); +} + +static void thunder_i2c_set_name(struct pci_dev *pdev, struct octeon_i2c *i2c, + char *name) +{ + u8 i2c_bus_id, soc_node; + resource_size_t start; + + start = pci_resource_start(pdev, PCI_CFG_REG_BAR_NUM); + soc_node = (start >> 44) & 0x3; + i2c_bus_id = (start >> 24) & 0x7; + snprintf(name, 10, "i2c%d", soc_node * 6 + i2c_bus_id); + + snprintf(i2c->adap.name, sizeof(i2c->adap.name), "thunderx-i2c-%d.%d", + soc_node, i2c_bus_id); +} + +static int thunder_i2c_probe_pci(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + struct device *dev = &pdev->dev; + struct device_node *node = NULL; + struct octeon_i2c *i2c; + char i2c_name[10]; + int ret = 0; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->dev = dev; + pci_set_drvdata(pdev, i2c); + ret = pci_enable_device(pdev); + if (ret) { + dev_err(dev, "Failed to enable PCI device\n"); + goto out_free_i2c; + } + + ret = pci_request_regions(pdev, DRV_NAME); + if (ret) { + dev_err(dev, "PCI request regions failed 0x%x\n", ret); + goto out_disable_device; + } + + i2c->twsi_base = pci_ioremap_bar(pdev, PCI_CFG_REG_BAR_NUM); + if (!i2c->twsi_base) { + dev_err(dev, "Cannot map CSR memory space\n"); + ret = -EINVAL; + goto out_release_regions; + } + + thunder_i2c_clock_enable(dev, i2c); + + thunder_i2c_set_name(pdev, i2c, i2c_name); + node = of_find_node_by_name(NULL, i2c_name); + if (!node || of_property_read_u32(node, "clock-frequency", + &i2c->twsi_freq)) + i2c->twsi_freq = TWSI_DFL_RATE; + + init_waitqueue_head(&i2c->queue); + + i2c->int_en = thunder_i2c_int_enable; + i2c->int_dis = thunder_i2c_int_disable; + i2c->hlc_int_en = thunder_i2c_hlc_int_enable; + i2c->hlc_int_dis = thunder_i2c_hlc_int_disable; + + ret = pci_enable_msix(pdev, &i2c->i2c_msix, 1); + if (ret) { + dev_err(dev, "Unable to enable MSI-X\n"); + goto out_unmap; + } + + ret = devm_request_irq(dev, i2c->i2c_msix.vector, octeon_i2c_isr, 0, + DRV_NAME, i2c); + if (ret < 0) { + dev_err(dev, "Failed to attach i2c interrupt\n"); + goto out_msix; + } + + ret = octeon_i2c_init_lowlevel(i2c); + if (ret) { + dev_err(dev, "Init low level failed\n"); + goto out_msix; + } + + octeon_i2c_set_clock(i2c); + + i2c->adap = thunderx_i2c_ops; + i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; + i2c->adap.timeout = msecs_to_jiffies(5); + i2c->adap.retries = 5; + i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info; + i2c->adap.dev.parent = dev; + i2c->adap.dev.of_node = pdev->dev.of_node; + i2c_set_adapdata(&i2c->adap, i2c); + + ret = i2c_add_adapter(&i2c->adap); + if (ret < 0) { + dev_err(dev, "Failed to add i2c adapter\n"); + goto out_irq; + } + + dev_info(i2c->dev, "probed\n"); + return 0; + +out_irq: + devm_free_irq(dev, i2c->i2c_msix.vector, i2c); +out_msix: + pci_disable_msix(pdev); +out_unmap: + iounmap(i2c->twsi_base); + thunder_i2c_clock_disable(dev, i2c->clk); +out_release_regions: + pci_release_regions(pdev); +out_disable_device: + pci_disable_device(pdev); +out_free_i2c: + pci_set_drvdata(pdev, NULL); + devm_kfree(dev, i2c); + return ret; +} + +static void thunder_i2c_remove_pci(struct pci_dev *pdev) +{ + struct octeon_i2c *i2c = pci_get_drvdata(pdev); + struct device *dev; + + if (!i2c) + return; + + dev = i2c->dev; + thunder_i2c_clock_disable(dev, i2c->clk); + i2c_del_adapter(&i2c->adap); + devm_free_irq(dev, i2c->i2c_msix.vector, i2c); + pci_disable_msix(pdev); + iounmap(i2c->twsi_base); + pci_release_regions(pdev); + pci_disable_device(pdev); + pci_set_drvdata(pdev, NULL); + devm_kfree(dev, i2c); +} + +static const struct pci_device_id thunder_i2c_pci_id_table[] = { + { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_THUNDER_TWSI) }, + { 0, } +}; + +MODULE_DEVICE_TABLE(pci, thunder_i2c_pci_id_table); + +static struct pci_driver thunder_i2c_pci_driver = { + .name = DRV_NAME, + .id_table = thunder_i2c_pci_id_table, + .probe = thunder_i2c_probe_pci, + .remove = thunder_i2c_remove_pci, +}; + +module_pci_driver(thunder_i2c_pci_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Fred Martin "); +MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC"); -- 1.9.1