From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8BD7AC43444 for ; Fri, 11 Jan 2019 23:12:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C8002184B for ; Fri, 11 Jan 2019 23:12:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="kR8fuvig" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726338AbfAKXMd (ORCPT ); Fri, 11 Jan 2019 18:12:33 -0500 Received: from mail-pl1-f193.google.com ([209.85.214.193]:46987 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726090AbfAKXMc (ORCPT ); Fri, 11 Jan 2019 18:12:32 -0500 Received: by mail-pl1-f193.google.com with SMTP id t13so7391915ply.13 for ; Fri, 11 Jan 2019 15:12:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=DD3AWaQ5dlSqwjbHrov4cby4Uzr+mkQKMJ7Qsnv+gXA=; b=kR8fuvigoPSrXn0YyxOsFubkMr/Hr7rN/HpmGIh8+CFzDwBQO897XrpKHVZEsBayP9 UXtPztgKGmDVN8522i4BpOUSIS+dMQzg4ERHwxQVg4IyHxDpoJzFzZAsQnEP1HoSicgA 1UEOghgYGhXKVcH1SHc82UiMnvE7wVCCtXDyQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=DD3AWaQ5dlSqwjbHrov4cby4Uzr+mkQKMJ7Qsnv+gXA=; b=jy1Vhx6dhhX2KKLNjGP7pNZ09tVmoibLI6T2RCJZYB0d+iI6CMM/lLr54aUUXI3huX x8KvMcNdcyH3ew855uu+w7fCeQfVFjvafVJtqEnJ+w+ZpyWJan2D1n91yeHJRrcvxWfY gUdosCnDmUgYQMlt+cfuR5Gqt4e0rQhEZK2XRxWuuUVyjJbcag5YHi1AcXcN72E80Qbb ZgZRpiOPjXJsAb4U//eD8AeyPrFBdV4qN406rx2zeSIqwVg9cSycTUfYm5Mv37h/9Uvw RRxD9fg1l1awCVJgHtGyyzM+OjW5swHYwLllkyHIs5hfqmoL3tbjbJ3gaMctiTqB+IzF vU3A== X-Gm-Message-State: AJcUukdvFKVaGGU2sml3Ejv8Trw3wGk8L9Ey2zfxolm7AFHEbZNI8EOL uGiwj2Qum+sHwddx0jfiKMS/og== X-Google-Smtp-Source: ALg8bN647zN3II0S0gFQp1T6b3MUp2RVEDDAAVsHLEJv1/vw5pvVVw11OD0DxSJBNrpKVwzmSBDRCw== X-Received: by 2002:a17:902:2ec1:: with SMTP id r59mr16719448plb.254.1547248350581; Fri, 11 Jan 2019 15:12:30 -0800 (PST) Received: from localhost ([2620:15c:202:1:75a:3f6e:21d:9374]) by smtp.gmail.com with ESMTPSA id m3sm138819142pff.173.2019.01.11.15.12.29 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 11 Jan 2019 15:12:29 -0800 (PST) Date: Fri, 11 Jan 2019 15:12:29 -0800 From: Matthias Kaehlcke To: Balakrishna Godavarthi Cc: Marcel Holtmann , Johan Hedberg , linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, hemantg@codeaurora.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v7 4/4] Bluetooth: btqca: inject command complete event during fw download Message-ID: <20190111231229.GI261387@google.com> References: <20181228114819.17479-1-bgodavar@codeaurora.org> <20181228114819.17479-5-bgodavar@codeaurora.org> <2C799DB5-8033-45B5-A790-A16F73641645@holtmann.org> <1FC4CC11-B070-4ACF-9107-857A4D392876@holtmann.org> <1ec946b46301124c90aa12abffeca176@codeaurora.org> <20190102221510.GQ261387@google.com> <20190110204328.GA261387@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org On Fri, Jan 11, 2019 at 07:53:43PM +0530, Balakrishna Godavarthi wrote: > Hi Matthias, > > On 2019-01-11 02:13, Matthias Kaehlcke wrote: > > Hi Balakrishna, > > > > On Thu, Jan 10, 2019 at 08:30:43PM +0530, Balakrishna Godavarthi wrote: > > > Hi Matthias, > > > > > > On 2019-01-03 03:45, Matthias Kaehlcke wrote: > > > > On Mon, Dec 31, 2018 at 11:34:46AM +0530, Balakrishna Godavarthi wrote: > > > > > Hi Marcel, > > > > > > > > > > On 2018-12-30 13:40, Marcel Holtmann wrote: > > > > > > Hi Balakrishna, > > > > > > > > > > > > > > > Latest qualcomm chips are not sending an command complete event for > > > > > > > > > every firmware packet sent to chip. They only respond with a vendor > > > > > > > > > specific event for the last firmware packet. This optimization will > > > > > > > > > decrease the BT ON time. Due to this we are seeing a timeout error > > > > > > > > > message logs on the console during firmware download. Now we are > > > > > > > > > injecting a command complete event once we receive an vendor > > > > > > > > > specific > > > > > > > > > event for the last RAM firmware packet. > > > > > > > > > Signed-off-by: Balakrishna Godavarthi > > > > > > > > > --- > > > > > > > > > drivers/bluetooth/btqca.c | 39 > > > > > > > > > ++++++++++++++++++++++++++++++++++++++- > > > > > > > > > drivers/bluetooth/btqca.h | 3 +++ > > > > > > > > > 2 files changed, 41 insertions(+), 1 deletion(-) > > > > > > > > > diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c > > > > > > > > > index ec9e03a6b778..0b533f65f652 100644 > > > > > > > > > --- a/drivers/bluetooth/btqca.c > > > > > > > > > +++ b/drivers/bluetooth/btqca.c > > > > > > > > > @@ -144,6 +144,7 @@ static void qca_tlv_check_data(struct > > > > > > > > > rome_config *config, > > > > > > > > > * In case VSE is skipped, only the last segment is acked. > > > > > > > > > */ > > > > > > > > > config->dnld_mode = tlv_patch->download_mode; > > > > > > > > > + config->dnld_type = config->dnld_mode; > > > > > > > > > BT_DBG("Total Length : %d bytes", > > > > > > > > > le32_to_cpu(tlv_patch->total_size)); > > > > > > > > > @@ -264,6 +265,31 @@ static int qca_tlv_send_segment(struct > > > > > > > > > hci_dev *hdev, int seg_size, > > > > > > > > > return err; > > > > > > > > > } > > > > > > > > > +static int qca_inject_cmd_complete_event(struct hci_dev *hdev) > > > > > > > > > +{ > > > > > > > > > + struct hci_event_hdr *hdr; > > > > > > > > > + struct hci_ev_cmd_complete *evt; > > > > > > > > > + struct sk_buff *skb; > > > > > > > > > + > > > > > > > > > + skb = bt_skb_alloc(sizeof(*hdr) + sizeof(*evt) + 1, GFP_KERNEL); > > > > > > > > > + if (!skb) > > > > > > > > > + return -ENOMEM; > > > > > > > > > + > > > > > > > > > + hdr = skb_put(skb, sizeof(*hdr)); > > > > > > > > > + hdr->evt = HCI_EV_CMD_COMPLETE; > > > > > > > > > + hdr->plen = sizeof(*evt) + 1; > > > > > > > > > + > > > > > > > > > + evt = skb_put(skb, sizeof(*evt)); > > > > > > > > > + evt->ncmd = 1; > > > > > > > > > + evt->opcode = HCI_OP_NOP; > > > > > > > > After looking a bit more at it I realize HCI_OP_NOP is not a good > > > > value in this case: > > > > > > > > static void hci_cmd_complete_evt(...) > > > > { > > > > ... > > > > > > > > if (*opcode != HCI_OP_NOP) > > > > cancel_delayed_work(&hdev->cmd_timer); > > > > > > > > ... > > > > } > > > > > > > > https://elixir.bootlin.com/linux/v4.19/source/net/bluetooth/hci_event.c#L3351 > > > > > > > > Cancelling the command timeout is precisely what we want. Not sure why > > > > the patch with HCI_OP_NOP makes the timeouts go away in most cases > > > > (but not e.g. when inserting an msleep(1000) after downloading the > > > > NVM. > > > > > > > > I suggest to pass the opcode of the command to be completed. > > > > > > > > > > > > > + > > > > > > > > > + skb_put_u8(skb, QCA_HCI_CC_SUCCESS); > > > > > > > > > + > > > > > > > > > + hci_skb_pkt_type(skb) = HCI_EVENT_PKT; > > > > > > > > > + > > > > > > > > > + return hci_recv_frame(hdev, skb); > > > > > > > > > +} > > > > > > > > > + > > > > > > > > > static int qca_download_firmware(struct hci_dev *hdev, > > > > > > > > > struct rome_config *config) > > > > > > > > > { > > > > > > > > > @@ -297,11 +323,22 @@ static int > > > > > > > > > qca_download_firmware(struct hci_dev *hdev, > > > > > > > > > ret = qca_tlv_send_segment(hdev, segsize, segment, > > > > > > > > > config->dnld_mode); > > > > > > > > > if (ret) > > > > > > > > > - break; > > > > > > > > > + goto out; > > > > > > > > > segment += segsize; > > > > > > > > > } > > > > > > > > > + /* Latest qualcomm chipsets are not sending a command > > > > > > > > > complete event > > > > > > > > > + * for every fw packet sent. They only respond with a > > > > > > > > > vendor specific > > > > > > > > > + * event for the last packet. This optimization in the chip will > > > > > > > > > + * decrease the BT in initialization time. Here we will > > > > > > > > > inject a command > > > > > > > > > + * complete event to avoid a command timeout error message. > > > > > > > > > + */ > > > > > > > > > + if ((config->dnld_type == ROME_SKIP_EVT_VSE_CC || > > > > > > > > > + config->dnld_type == ROME_SKIP_EVT_VSE)) > > > > > > > > > + return qca_inject_cmd_complete_event(hdev); > > > > > > > > > + > > > > > > > > have you actually considered using __hci_cmd_send in that case. It is > > > > > > > > allowed for vendor OGF to use that command. I see you actually do use > > > > > > > > it and now I am failing to understand what this is for. > > > > > > > [Bala]: thanks for reviewing the change. > > > > > > > > > > > > > > __hci_cmd_send() can be used only to send the command to the chip. > > > > > > > it will not wait for the response for the command sent. > > > > > > > > > > > > > > as you know that every vendor command sent to chip will respond with > > > > > > > vendor specific event and command complete event. > > > > > > > but in our case chip will only respond with vendor specific event > > > > > > > only. so we are injecting command complete event. > > > > > > > > > > > > and __hci_cmd_sync_ev is also not working for you? However since you > > > > > > are not waiting for the vendor event anyway and just injecting > > > > > > cmd_complete, I wonder what’s the difference in just using > > > > > > __hci_cmd_send and not bothering to wait or inject at all. I am > > > > > > failing to see where this injection makes a difference. > > > > > > > > > > > > For me it is a big difference if we are injecting one event like in > > > > > > the case of Intel compared to injecting one for every command. It will > > > > > > show a wrong picture in btmon and that is a bad idea. > > > > > > > > > > > > Regards > > > > > > > > > > > > Marcel > > > > > > > > > > [Bala]: here is the use case, when ever we download the fw packets > > > > > i.e. RAM > > > > > image, for every command sent(i.e. fw packet) from > > > > > the host chip will respond with an vendor specific event and command > > > > > complete event. > > > > > > > > > > the above is taking more time to setup the BT device. then we came > > > > > up with > > > > > solution where we enable flags in fw file (i.e. RAM image header) > > > > > whether to wait for event to be received or sent the total packets > > > > > and wait > > > > > for the events for the last packet. > > > > > > > > > > So currently we are handling both the cases in the code. i.e wait > > > > > for event > > > > > for all packet or wait for an event for the last packet. > > > > > > > > > > but in the second case i.e. wait for event for the last packet sent, > > > > > we are > > > > > only receiving an vendor specific event from chip which holds the > > > > > status of > > > > > fw download. > > > > > > > > > > so as __hci_cmd_sync_ev() requires an command complete event. so we > > > > > are > > > > > injecting it after the vendor specific event received for the last > > > > > packet. > > > > > > > > > > This helps to overcome 0xfc00 timeout error logging on console. > > > > > > > > Some more details: > > > > > > > > The timeout error is actually from reading the 'SoC version', which > > > > uses the same command code as the firmware download > > > > (EDL_PATCH_CMD_OPCODE). Without reading the 'SoC version' it would be > > > > from the command to write the first firmware segment. > > > > > > > > If the download of a firmware binary takes >= 2s (HCI_CMD_TIMEOUT) the > > > > timeout would still occur. If necessary this could be mitigated by > > > > injecting some command complete events during the firmware download, > > > > though I expect Marcel wouldn't be overly happy with that, since it > > > > would affect btmon even more. > > > > > > > > Regards > > > > > > > > Matthias > > > > > > [Bala]: Basically every vendor specific command we sent to chip, > > > chip should respond with an vendor specific event followed by an > > > command > > > complete event > > > or some times it will only respond with an command complete event. > > > but in any case command complete event is mandatory to all the > > > command we > > > sent to the chip. > > > > Is this ("command complete event is mandatory to all the command we > > sent to the chip") a description of what the chip actually does, or > > what it should be doing according to the spec? > > > > As mentioned earlier, the timeout we see originates from reading the > > SoC version: > > > > diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c > > index 0b533f65f652fc..1e484e61799571 100644 > > --- a/drivers/bluetooth/btqca.c > > +++ b/drivers/bluetooth/btqca.c > > @@ -400,6 +400,10 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t > > baudrate, > > return err; > > } > > > > + printk("DBG: ZZZzzzzzzz\n"); > > + msleep(2500); > > + printk("DBG: good morning!\n"); > > + > > /* Download NVM configuration */ > > config.type = TLV_TYPE_NVM; > > if (soc_type == QCA_WCN3990) > > > > When you boot with this patch you'll see something like this: > > > > [ 15.531365] DBG: reading SoC version > > [ 15.544963] DBG: ZZZzzzzzzz > > [ 17.590282] Bluetooth: hci0: command 0xfc00 tx timeout > > [ 18.099110] DBG: good morning! > > > > [Bala]: my previous analysis were wrong. thanks for pointing me to the > correct issue. > i am able to see timeout after version command.(used some sleep) > here is the reason for it. > > 01 00 fc 01 19 (we send the command to chip to request version) > 04 ff 0e 00 02 0a 00 00 00 01 00 01 02 14 02 01 40(chip will respond > with the vendor specific event payload will be chip version) > 04 0e 04 01 00 00 00(command complete event) > > issue is with command complete event. ideally command complete event > payload holds the command for which chip sends command complete event. > > breaking the command > > 04 : event packet (fixed) > 0e : command complete event(fixed) > 04 : size of the payload, > > 01 : no of commands in the payload > 00 : OCF (opocde lsb) > 00 : OGF (opcode msb) > 00 : status of command executed, > > payload is form byte 4 to byte 7. which hold the command i.e opcode > form the above response opcode is 0x0000. ideally this should be > 0xfc00 > because the command complete response from the chip is for the command > 0xfc00. > > Checked with Chip firmware dev team for the reason, it was an > limitation or an bug in the chip ROM firmware > in the current chipset, which is fixed in the coming chipset. > > so we expect the command 0xfc00 but recevuies 0x00. so that is the > reason we see an timeouts. > for all the vendor commands we receive 0x0000 in the command complete > event. Thanks for your analysis. It is unfortunate (though not unexpected) that this is a problem in the ROM were we can't fix it, but at least the FW team is aware of it and fixed it for future hardware. > if comes a new question how are we not seeing an 0xfc00 when we inject > an command complete event. > i experimented this patch, when i inject the command complete event > from the soc version still i can see the command timeouts. I don't see command timeouts when injecting a command complete event after reading the SoC version. I suspect you still use patch which injects a command complete event with HCI_OP_NOP, which is precisely what the chip does ... > The reason for no timeouts error, we are injecting an command complete > after last packet sent out, so this injection helps > .bin file to speed out it download part, so as the bin is dumped > fastly we send an HCI RESET Comamnd where we recevie an command complete > event > with non zero opcode which is cancelling the command timeout timer. > > when we inject command complete event, in short we are completing > setup process in less than 2 seconds(command timeout timer value), > so before 2 seconds we are sending an HCI RESET command whose command > complete event opcode value is an non zero (which cancels the command > timeout timer) I agree that HCI_RESET cancels the command timeout timer if it is sent before the 2s timout expires, but I have doubts on the part about command complete events. In my observations there are no command timeouts if a command complete (with opcode != HCI_OP_NOP) is injected after the firmware download, even if a 3s sleep is added before sending the HCI_RESET. > > > In our case, we have an two fw files i.e. *.tlv and *.bin. > > > tlv is an RAM image of the chip where as bin is an nvm image of the > > > chip. so > > > tlv will be of > > > more size which require an lot more time to dump the file in to chip, > > > while dumping the tlv, we divide tlv as packet of size 245 bytes and > > > send > > > them as an command packet to the chip. chip should respond with an > > > command > > > complete event. > > > then only we will send the next packet. but size of the tlv is > > > large, to > > > optimize this we will > > > not wait for the either an vendor specific event or an command > > > complete > > > event. > > > > Let's make sure we have an accurate picture, which of the following is > > correct: > > > > 1. the chip sends a command complete event after each packet, as an > > optimization the BT driver doesn't wait for it > > > > 2. as an optimization the chip does not send a command complete event > > and the driver has to deal with it > > > > My understanding is that it's 2), but the wording above seems to > > describe 1) > > > [Bala]: point 2 is true. Thanks for the confirmation > > > But as we need to be on the sync, i.e. whether are we sending an > > > correct > > > packets or not, > > > for the last fw packet we sent to the chip.. chip will to do an CRC > > > check > > > for the total no of packets received and respond with an vendor > > > specific > > > event. > > > > > > We decode the vendor specific event and decide whether the fw > > > download is > > > success or not. here we send an fw packet as command so stack > > > expects an > > > command complete event. > > > where this is missing from the chip. this is expected behavior from > > > chip. > > > > > > So currently i am inject an command complete event after receiving > > > an vendor > > > event for the last packet of the tlv. > > > > And the same for the .bin if I'm not mistaken. > > > > > This we inject only once for the last command packet sent to the chip. > > > i don't think this will effect the btmon. > > > > I don't know enough about btmon to comment on that, in any case Marcel > > raised concerns. > > > > And I think my comment that triggered this disucssion remains true: > > > > > If the download of a firmware binary takes >= 2s (HCI_CMD_TIMEOUT) the > > > timeout would still occur. If necessary this could be mitigated by > > > injecting some command complete events during the firmware download. > > > > Not sure it's a likely case, it might be an issue with larger firmware > > files and/or slower UART speeds. > > > > Thanks > > > > Matthias > > [Bala]: i don't think it is a good idea to handle this kind of limitations > in the HOST driver. Where do you intend to handle it then? Ideally it would be fixed in the ROM FW, but that doesn't seem a viable option. Cheers Matthias