Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752310AbdFZTaY (ORCPT ); Mon, 26 Jun 2017 15:30:24 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:60057 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751615AbdFZT3v (ORCPT ); Mon, 26 Jun 2017 15:29:51 -0400 From: Eddie James To: linux-kernel@vger.kernel.org Cc: linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, wsa@the-dreams.de, robh+dt@kernel.org, gregkh@linuxfoundation.org, jk@ozlabs.org, joel@jms.id.au, andrew@aj.id.au, eajames@linux.vnet.ibm.com, "Edward A. James" Subject: [PATCH 1/6] drivers/i2c: Add FSI-attached I2C master algorithm Date: Mon, 26 Jun 2017 14:29:30 -0500 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1498505375-1454-1-git-send-email-eajames@linux.vnet.ibm.com> References: <1498505375-1454-1-git-send-email-eajames@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17062619-0020-0000-0000-00000C3E4A83 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007281; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000214; SDB=6.00879079; UDB=6.00438095; IPR=6.00659233; BA=6.00005443; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015957; XFM=3.00000015; UTC=2017-06-26 19:29:47 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17062619-0021-0000-0000-00005CF8A18E Message-Id: <1498505375-1454-2-git-send-email-eajames@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-06-26_15:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1706260319 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8344 Lines: 298 From: "Edward A. James" Add register definitions for FSI-attached I2C master and functions to access those registers over FSI. Add an FSI driver so that our I2C bus is probed up during an FSI scan. Signed-off-by: Edward A. James --- drivers/i2c/busses/Kconfig | 11 ++ drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-fsi.c | 245 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 257 insertions(+) create mode 100644 drivers/i2c/busses/i2c-fsi.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index ed7106e..47bba71 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -1260,4 +1260,15 @@ config I2C_OPAL This driver can also be built as a module. If so, the module will be called as i2c-opal. +config I2C_FSI + tristate "FSI I2C driver" + depends on FSI + help + Driver for FSI bus attached I2C masters. These are I2C masters that + are connected to the system over a FSI bus, instead of the more + common PCI or MMIO interface. + + This driver can also be built as a module. If so, the module will be + called as i2c-fsi. + endmenu diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index c89a431..f99ea5d 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -126,5 +126,6 @@ obj-$(CONFIG_I2C_PCA_ISA) += i2c-pca-isa.o obj-$(CONFIG_I2C_SIBYTE) += i2c-sibyte.o obj-$(CONFIG_I2C_XGENE_SLIMPRO) += i2c-xgene-slimpro.o obj-$(CONFIG_SCx200_ACB) += scx200_acb.o +obj-$(CONFIG_I2C_FSI) += i2c-fsi.o ccflags-$(CONFIG_I2C_DEBUG_BUS) := -DDEBUG diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c new file mode 100644 index 0000000..f8ea94e --- /dev/null +++ b/drivers/i2c/busses/i2c-fsi.c @@ -0,0 +1,245 @@ +/* + * Copyright 2017 IBM Corporation + * + * Eddie James + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define FSI_ENGID_I2C 0x7 + +/* Find left shift from first set bit in m */ +#define MASK_TO_LSH(m) (__builtin_ffsll(m) - 1ULL) + +/* Extract field m from v */ +#define GETFIELD(m, v) (((v) & (m)) >> MASK_TO_LSH(m)) + +/* Set field m of v to val */ +#define SETFIELD(m, v, val) \ + (((v) & ~(m)) | ((((typeof(v))(val)) << MASK_TO_LSH(m)) & (m))) + +#define I2C_DEFAULT_CLK_DIV 6 + +/* i2c registers */ +#define I2C_FSI_FIFO 0x00 +#define I2C_FSI_CMD 0x04 +#define I2C_FSI_MODE 0x08 +#define I2C_FSI_WATER_MARK 0x0C +#define I2C_FSI_INT_MASK 0x10 +#define I2C_FSI_INT_COND 0x14 +#define I2C_FSI_OR_INT_MASK 0x14 +#define I2C_FSI_INTS 0x18 +#define I2C_FSI_AND_INT_MASK 0x18 +#define I2C_FSI_STAT 0x1C +#define I2C_FSI_RESET_I2C 0x1C +#define I2C_FSI_ESTAT 0x20 +#define I2C_FSI_RESET_ERR 0x20 +#define I2C_FSI_RESID_LEN 0x24 +#define I2C_FSI_SET_SCL 0x24 +#define I2C_FSI_PORT_BUSY 0x28 +#define I2C_FSI_RESET_SCL 0x2C +#define I2C_FSI_SET_SDA 0x30 +#define I2C_FSI_RESET_SDA 0x34 + +/* cmd register */ +#define I2C_CMD_WITH_START 0x80000000 +#define I2C_CMD_WITH_ADDR 0x40000000 +#define I2C_CMD_RD_CONT 0x20000000 +#define I2C_CMD_WITH_STOP 0x10000000 +#define I2C_CMD_FORCELAUNCH 0x08000000 +#define I2C_CMD_ADDR 0x00fe0000 +#define I2C_CMD_READ 0x00010000 +#define I2C_CMD_LEN 0x0000ffff + +/* mode register */ +#define I2C_MODE_CLKDIV 0xffff0000 +#define I2C_MODE_PORT 0x0000fc00 +#define I2C_MODE_ENHANCED 0x00000008 +#define I2C_MODE_DIAG 0x00000004 +#define I2C_MODE_PACE_ALLOW 0x00000002 +#define I2C_MODE_WRAP 0x00000001 + +/* watermark register */ +#define I2C_WATERMARK_HI 0x0000f000 +#define I2C_WATERMARK_LO 0x000000f0 + +#define I2C_FIFO_HI_LVL 4 +#define I2C_FIFO_LO_LVL 4 + +/* interrupt register */ +#define I2C_INT_INV_CMD 0x00008000 +#define I2C_INT_PARITY 0x00004000 +#define I2C_INT_BE_OVERRUN 0x00002000 +#define I2C_INT_BE_ACCESS 0x00001000 +#define I2C_INT_LOST_ARB 0x00000800 +#define I2C_INT_NACK 0x00000400 +#define I2C_INT_DAT_REQ 0x00000200 +#define I2C_INT_CMD_COMP 0x00000100 +#define I2C_INT_STOP_ERR 0x00000080 +#define I2C_INT_BUSY 0x00000040 +#define I2C_INT_IDLE 0x00000020 + +#define I2C_INT_ENABLE 0x0000ff80 +#define I2C_INT_ERR 0x0000fcc0 + +/* status register */ +#define I2C_STAT_INV_CMD 0x80000000 +#define I2C_STAT_PARITY 0x40000000 +#define I2C_STAT_BE_OVERRUN 0x20000000 +#define I2C_STAT_BE_ACCESS 0x10000000 +#define I2C_STAT_LOST_ARB 0x08000000 +#define I2C_STAT_NACK 0x04000000 +#define I2C_STAT_DAT_REQ 0x02000000 +#define I2C_STAT_CMD_COMP 0x01000000 +#define I2C_STAT_STOP_ERR 0x00800000 +#define I2C_STAT_MAX_PORT 0x000f0000 +#define I2C_STAT_ANY_INT 0x00008000 +#define I2C_STAT_SCL_IN 0x00000800 +#define I2C_STAT_SDA_IN 0x00000400 +#define I2C_STAT_PORT_BUSY 0x00000200 +#define I2C_STAT_SELF_BUSY 0x00000100 +#define I2C_STAT_FIFO_COUNT 0x000000ff + +#define I2C_STAT_ERR 0xfc800000 +#define I2C_STAT_ANY_RESP 0xff800000 + +/* extended status register */ +#define I2C_ESTAT_FIFO_SZ 0xff000000 +#define I2C_ESTAT_SCL_IN_SY 0x00008000 +#define I2C_ESTAT_SDA_IN_SY 0x00004000 +#define I2C_ESTAT_S_SCL 0x00002000 +#define I2C_ESTAT_S_SDA 0x00001000 +#define I2C_ESTAT_M_SCL 0x00000800 +#define I2C_ESTAT_M_SDA 0x00000400 +#define I2C_ESTAT_HI_WATER 0x00000200 +#define I2C_ESTAT_LO_WATER 0x00000100 +#define I2C_ESTAT_PORT_BUSY 0x00000080 +#define I2C_ESTAT_SELF_BUSY 0x00000040 +#define I2C_ESTAT_VERSION 0x0000001f + +struct fsi_i2c_master { + struct fsi_device *fsi; + u8 fifo_size; +}; + +static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg, + u32 *data) +{ + int rc; + __be32 data_be; + + rc = fsi_device_read(fsi, reg, &data_be, sizeof(data_be)); + if (rc) + return rc; + + *data = be32_to_cpu(data_be); + + return 0; +} + +static int fsi_i2c_write_reg(struct fsi_device *fsi, unsigned int reg, + u32 *data) +{ + __be32 data_be = cpu_to_be32(*data); + + return fsi_device_write(fsi, reg, &data_be, sizeof(data_be)); +} + +static int fsi_i2c_dev_init(struct fsi_i2c_master *i2c) +{ + int rc; + u32 mode = I2C_MODE_ENHANCED, extended_status, watermark = 0; + u32 interrupt = 0; + + /* since we use polling, disable interrupts */ + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_INT_MASK, &interrupt); + if (rc) + return rc; + + mode = SETFIELD(I2C_MODE_CLKDIV, mode, I2C_DEFAULT_CLK_DIV); + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_MODE, &mode); + if (rc) + return rc; + + rc = fsi_i2c_read_reg(i2c->fsi, I2C_FSI_ESTAT, &extended_status); + if (rc) + return rc; + + i2c->fifo_size = GETFIELD(I2C_ESTAT_FIFO_SZ, extended_status); + watermark = SETFIELD(I2C_WATERMARK_HI, watermark, + i2c->fifo_size - I2C_FIFO_HI_LVL); + watermark = SETFIELD(I2C_WATERMARK_LO, watermark, + I2C_FIFO_LO_LVL); + + rc = fsi_i2c_write_reg(i2c->fsi, I2C_FSI_WATER_MARK, &watermark); + + return rc; +} + +static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num) +{ + return -EOPNOTSUPP; +} + +static u32 fsi_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_10BIT_ADDR; +} + +static const struct i2c_algorithm fsi_i2c_algorithm = { + .master_xfer = fsi_i2c_xfer, + .functionality = fsi_i2c_functionality, +}; + +static int fsi_i2c_probe(struct device *dev) +{ + struct fsi_i2c_master *i2c; + int rc; + + i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL); + if (!i2c) + return -ENOMEM; + + i2c->fsi = to_fsi_dev(dev); + + rc = fsi_i2c_dev_init(i2c); + if (rc) + return rc; + + dev_set_drvdata(dev, i2c); + + return 0; +} + +static const struct fsi_device_id fsi_i2c_ids[] = { + { FSI_ENGID_I2C, FSI_VERSION_ANY }, + { 0 } +}; + +static struct fsi_driver fsi_i2c_driver = { + .id_table = fsi_i2c_ids, + .drv = { + .name = "i2cm-fsi", + .bus = &fsi_bus_type, + .probe = fsi_i2c_probe, + }, +}; + +module_fsi_driver(fsi_i2c_driver); + +MODULE_AUTHOR("Eddie James "); +MODULE_DESCRIPTION("FSI attached I2C master"); +MODULE_LICENSE("GPL"); -- 1.8.3.1