Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753416AbdC2RpF (ORCPT ); Wed, 29 Mar 2017 13:45:05 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:52052 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932792AbdC2Rod (ORCPT ); Wed, 29 Mar 2017 13:44:33 -0400 From: Christopher Bostic To: robh+dt@kernel.org, mark.rutland@arm.com, linux@armlinux.org.uk, rostedt@goodmis.org, mingo@redhat.com, gregkh@linuxfoundation.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Jeremy Kerr , joel@jms.id.au, linux-kernel@vger.kernel.org, andrew@aj.id.au, alistair@popple.id.au, benh@kernel.crashing.org, Chris Bostic Subject: [PATCH v4 23/23] drivers/fsi: Use asynchronous slave mode Date: Wed, 29 Mar 2017 12:43:40 -0500 X-Mailer: git-send-email 2.10.1 (Apple Git-78) In-Reply-To: <20170329174340.89109-1-cbostic@linux.vnet.ibm.com> References: <20170329174340.89109-1-cbostic@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17032917-0028-0000-0000-0000074F6DA1 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006872; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000206; SDB=6.00840412; UDB=6.00413637; IPR=6.00618406; BA=6.00005248; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00014855; XFM=3.00000013; UTC=2017-03-29 17:44:29 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17032917-0029-0000-0000-000034AE1209 Message-Id: <20170329174340.89109-24-cbostic@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-03-29_13:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1702020001 definitions=main-1703290150 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2862 Lines: 96 From: Jeremy Kerr For slaves that are behind a software-clocked master, we want FSI CFAMs to run asynchronously to the FSI clock, so set up our slaves to be in async mode. Signed-off-by: Jeremy Kerr Signed-off-by: Chris Bostic --- drivers/fsi/fsi-core.c | 22 +++++++++++++++++++++- drivers/fsi/fsi-master-gpio.c | 1 + drivers/fsi/fsi-master.h | 2 ++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/fsi/fsi-core.c b/drivers/fsi/fsi-core.c index 747d0e3..a6ed34f 100644 --- a/drivers/fsi/fsi-core.c +++ b/drivers/fsi/fsi-core.c @@ -47,6 +47,7 @@ #define FSI_SMODE 0x0 /* R/W: Mode register */ #define FSI_SISC 0x8 /* R/W: Interrupt condition */ #define FSI_SSTAT 0x14 /* R : Slave status */ +#define FSI_LLMODE 0x100 /* R/W: Link layer mode register */ /* * SMODE fields @@ -62,6 +63,11 @@ #define FSI_SMODE_LBCRR_SHIFT 8 /* Clk ratio shift */ #define FSI_SMODE_LBCRR_MASK 0xf /* Clk ratio mask */ +/* + * LLMODE fields + */ +#define FSI_LLMODE_ASYNC 0x1 + #define FSI_SLAVE_SIZE_23b 0x800000 static DEFINE_IDA(master_ida); @@ -560,8 +566,8 @@ static void fsi_slave_release(struct device *dev) static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id) { + uint32_t chip_id, llmode; struct fsi_slave *slave; - uint32_t chip_id; uint8_t crc; int rc; @@ -597,6 +603,20 @@ static int fsi_slave_init(struct fsi_master *master, int link, uint8_t id) return -ENODEV; } + /* If we're behind a master that doesn't provide a self-running bus + * clock, put the slave into async mode + */ + if (master->flags & FSI_MASTER_FLAG_SWCLOCK) { + llmode = cpu_to_be32(FSI_LLMODE_ASYNC); + rc = fsi_master_write(master, link, id, + FSI_SLAVE_BASE + FSI_LLMODE, + &llmode, sizeof(llmode)); + if (rc) + dev_warn(&master->dev, + "can't set llmode on slave:%02x:%02x %d\n", + link, id, rc); + } + /* We can communicate with a slave; create the slave device and * register. */ diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c index 84d5595..f3fcede 100644 --- a/drivers/fsi/fsi-master-gpio.c +++ b/drivers/fsi/fsi-master-gpio.c @@ -573,6 +573,7 @@ static int fsi_master_gpio_probe(struct platform_device *pdev) master->gpio_mux = gpio; master->master.n_links = 1; + master->master.flags = FSI_MASTER_FLAG_SWCLOCK; master->master.read = fsi_master_gpio_read; master->master.write = fsi_master_gpio_write; master->master.term = fsi_master_gpio_term; diff --git a/drivers/fsi/fsi-master.h b/drivers/fsi/fsi-master.h index d6a4885..fd39924 100644 --- a/drivers/fsi/fsi-master.h +++ b/drivers/fsi/fsi-master.h @@ -19,6 +19,8 @@ #include +#define FSI_MASTER_FLAG_SWCLOCK 0x1 + struct fsi_master { struct device dev; int idx; -- 1.8.2.2