From patchwork Fri May 20 06:32:03 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Shan X-Patchwork-Id: 624317 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3r9ynQ6NvTz9t6B for ; Fri, 20 May 2016 16:33:46 +1000 (AEST) Received: from ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 3r9ynQ5XvjzDqF0 for ; Fri, 20 May 2016 16:33:46 +1000 (AEST) X-Original-To: skiboot@lists.ozlabs.org Delivered-To: skiboot@lists.ozlabs.org Received: from e23smtp01.au.ibm.com (e23smtp01.au.ibm.com [202.81.31.143]) (using TLSv1.2 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3r9yn65Dc9zDqBZ for ; Fri, 20 May 2016 16:33:30 +1000 (AEST) Received: from localhost by e23smtp01.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Fri, 20 May 2016 16:33:27 +1000 X-IBM-Helo: d23dlp03.au.ibm.com X-IBM-MailFrom: gwshan@linux.vnet.ibm.com X-IBM-RcptTo: skiboot@lists.ozlabs.org Received: from d23relay08.au.ibm.com (d23relay08.au.ibm.com [9.185.71.33]) by d23dlp03.au.ibm.com (Postfix) with ESMTP id E55663578053 for ; Fri, 20 May 2016 16:33:26 +1000 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay08.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u4K6XI7q1245662 for ; Fri, 20 May 2016 16:33:26 +1000 Received: from d23av02.au.ibm.com (localhost [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u4K6Wsqp014520 for ; Fri, 20 May 2016 16:32:54 +1000 Received: from ozlabs.au.ibm.com (ozlabs.au.ibm.com [9.192.253.14]) by d23av02.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id u4K6WswH013828; Fri, 20 May 2016 16:32:54 +1000 Received: from bran.ozlabs.ibm.com (haven.au.ibm.com [9.192.254.114]) by ozlabs.au.ibm.com (Postfix) with ESMTP id A97BEA025B; Fri, 20 May 2016 16:32:29 +1000 (AEST) Received: from gwshan (shangw.ozlabs.ibm.com [10.61.2.199]) by bran.ozlabs.ibm.com (Postfix) with ESMTP id ABAF4E3A8C; Fri, 20 May 2016 16:32:29 +1000 (AEST) Received: by gwshan (Postfix, from userid 1000) id 85BB5942543; Fri, 20 May 2016 16:32:29 +1000 (AEST) From: Gavin Shan To: skiboot@lists.ozlabs.org Date: Fri, 20 May 2016 16:32:03 +1000 Message-Id: <1463725945-12916-2-git-send-email-gwshan@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1463725945-12916-1-git-send-email-gwshan@linux.vnet.ibm.com> References: <1463725945-12916-1-git-send-email-gwshan@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16052006-1618-0000-0000-000045E2C94C X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused Subject: [Skiboot] [PATCH v11 01/23] hw/p8-i2c: Allow to set I2C request timeout X-BeenThere: skiboot@lists.ozlabs.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: Mailing list for skiboot development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: alistair@popple.id.au MIME-Version: 1.0 Errors-To: skiboot-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Skiboot" Prior to PCI enumeration, the PHB slot's power state might be changed during fundamental reset. The fundamental reset is implemented by state machine and it's driven by a polling mechanism in predetermined interval (A). On the other hand, PCI slot's power supply is controlled by I2C chip on Firenze platform. It means the PCI slot's power supply state is changed through I2C request which has a timeout timer running in variable interval (B). Comparing to (A), (B) is small and short. That means I2C timeout is reached before first poll running in interval of (A). It's unexpected behaviour. This allows to set I2C request timeout ((B)) to avoid the issue. Signed-off-by: Gavin Shan Reviewed-by: Stewart Smith --- hw/p8-i2c.c | 25 +++++++++++++++++++++++-- include/i2c.h | 9 +++++++++ 2 files changed, 32 insertions(+), 2 deletions(-) diff --git a/hw/p8-i2c.c b/hw/p8-i2c.c index 593eb88..fde9a80 100644 --- a/hw/p8-i2c.c +++ b/hw/p8-i2c.c @@ -386,10 +386,15 @@ static int p8_i2c_prog_mode(struct p8_i2c_master_port *port, bool enhanced_mode) static void p8_i2c_complete_request(struct p8_i2c_master *master, struct i2c_request *req, int ret) { + struct p8_i2c_request *request = + container_of(req, struct p8_i2c_request, req); + /* We only complete the current top level request */ assert(req == list_top(&master->req_list, struct i2c_request, link)); cancel_timer_async(&master->timeout); + request->timeout = 0ul; + list_del(&req->link); master->state = state_idle; req->result = ret; @@ -973,8 +978,12 @@ static int p8_i2c_start_request(struct p8_i2c_master *master, now = schedule_timer(&master->poller, master->poll_interval); /* Calculate and start timeout */ - tbytes = req->rw_len + req->offset_bytes + 2; - request->timeout = now + tbytes * master->byte_timeout; + if (request->timeout) { + request->timeout += now; + } else { + tbytes = req->rw_len + req->offset_bytes + 2; + request->timeout = now + tbytes * master->byte_timeout; + } /* Start the timeout */ schedule_timer_at(&master->timeout, request->timeout); @@ -1046,6 +1055,15 @@ static void p8_i2c_free_request(struct i2c_request *req) free(request); } +static void p8_i2c_set_request_timeout(struct i2c_request *req, + uint64_t duration) +{ + struct p8_i2c_request *request = + container_of(req, struct p8_i2c_request, req); + + request->timeout = msecs_to_tb(duration); +} + static inline uint32_t p8_i2c_get_bit_rate_divisor(uint32_t lb_freq, uint32_t bus_speed) { @@ -1093,6 +1111,8 @@ static void p8_i2c_timeout(struct timer *t __unused, void *data, uint64_t now) DBG("I2C: Timeout with request not expired\n"); goto exit; } + + request->timeout = 0ul; port = container_of(req->bus, struct p8_i2c_master_port, bus); /* Allright, we have a request and it has timed out ... */ @@ -1372,6 +1392,7 @@ static void p8_i2c_init_one(struct dt_node *i2cm, enum p8_i2c_master_type type) port->bus.queue_req = p8_i2c_queue_request; port->bus.alloc_req = p8_i2c_alloc_request; port->bus.free_req = p8_i2c_free_request; + port->bus.set_req_timeout = p8_i2c_set_request_timeout; i2c_add_bus(&port->bus); /* Add OPAL properties to the bus node */ diff --git a/include/i2c.h b/include/i2c.h index dea0644..83c6ec5 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -26,6 +26,8 @@ struct i2c_bus { int (*queue_req)(struct i2c_request *req); struct i2c_request *(*alloc_req)(struct i2c_bus *bus); void (*free_req)(struct i2c_request *req); + void (*set_req_timeout)(struct i2c_request *req, + uint64_t duration); }; /* @@ -80,6 +82,13 @@ static inline int i2c_queue_req(struct i2c_request *req) return req->bus->queue_req(req); } +static inline void i2c_set_req_timeout(struct i2c_request *req, + uint64_t duration) +{ + if (req->bus->set_req_timeout) + req->bus->set_req_timeout(req, duration); +} + /* P8 implementation details */ extern void p8_i2c_init(void); extern void p8_i2c_interrupt(uint32_t chip_id);