From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthias Kaehlcke Subject: Re: [PATCH v7 4/4] Bluetooth: btqca: inject command complete event during fw download Date: Fri, 8 Feb 2019 13:05:25 -0800 Message-ID: <20190208210525.GO117604@google.com> References: <20190110204328.GA261387@google.com> <20190111231229.GI261387@google.com> <5ef0fa1eca4a278ce31c88ef34c7c649@codeaurora.org> <20190115012002.GP261387@google.com> <6889ee31f9700659109c7b772bef76d9@codeaurora.org> <20190116195716.GR261387@google.com> <4641fce775b6d38b58ae8b70dd622d53@codeaurora.org> <7B2D2E74-925A-4C70-9641-2B7EA5721B4B@holtmann.org> <20190118210346.GA261387@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: Content-Disposition: inline In-Reply-To: <20190118210346.GA261387@google.com> Sender: linux-kernel-owner@vger.kernel.org To: Marcel Holtmann Cc: Balakrishna Godavarthi , Johan Hedberg , linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, hemantg@codeaurora.org, linux-arm-msm@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org On Fri, Jan 18, 2019 at 01:03:46PM -0800, Matthias Kaehlcke wrote: > Hi Marcel, > > On Fri, Jan 18, 2019 at 09:57:14AM +0100, Marcel Holtmann wrote: > > Hi Balakrishna, > > > > >>> On 2019-01-15 06:50, Matthias Kaehlcke wrote: > > >>> > On Mon, Jan 14, 2019 at 09:21:25PM +0530, Balakrishna Godavarthi wrote: > > >>> > > On 2019-01-12 04:42, Matthias Kaehlcke wrote: > > >>> > > > 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 ... > > >>> > > > > > >>> > > [Bala]: i am seeing command timeout after injecting cc event after > > >>> > > read > > >>> > > version request. > > >>> > > > > >>> > > > > 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. > > >>> > > > > > >>> > > > > >>> > > [Bala]: add sleep before sending HCI reset, oxfc00 timeout observed. > > >>> > > > >>> > Please double check your setup. Are you 100% sure you are not still > > >>> > sending HCI_OP_NOP as opcode? > > >>> > > > >>> [Bala]: sorry i am injecting the HCI_OP_NOP, so that is the reason we have > > >>> an timeouts. > > >>> yes if the opcode 0x42 injected, no timeouts are observed. > > >> Please don't use 0x42 (at least not as literal) when you respin, I > > >> only chose this value to illustrate that it's really the injected > > >> command which cancels the timer. You might want to add a > > >> QCA_HCI_OP_DUMMY or similar, to make clear that the value doesn't > > >> matter (as long as it isn't an actual opcode). With a define I don't > > >> really care if you use 0x01, 0x42 or any other non-opcode value. > > > > > > [Bala]: will not use 0x42, will use an opcode 0xfc00. > > > > > >>> > This is the diff I use for debugging on top of your patchset: > > >>> > > > >>> > diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c > > >>> > index 0b533f65f652fc..5bb9e0ca7c348b 100644 > > >>> > --- a/drivers/bluetooth/btqca.c > > >>> > +++ b/drivers/bluetooth/btqca.c > > >>> > @@ -27,6 +27,8 @@ > > >>> > > > >>> > #define VERSION "0.1" > > >>> > > > >>> > +static int qca_inject_cmd_complete_event(struct hci_dev *hdev); > > >>> > + > > >>> > int qca_read_soc_version(struct hci_dev *hdev, u32 *soc_version) > > >>> > { > > >>> > struct sk_buff *skb; > > >>> > @@ -84,6 +86,11 @@ int qca_read_soc_version(struct hci_dev *hdev, u32 > > >>> > *soc_version) > > >>> > if (*soc_version == 0) > > >>> > err = -EILSEQ; > > >>> > > > >>> > + qca_inject_cmd_complete_event(hdev); > > >>> > + printk("DBG: ZZZzzzzzzz\n"); > > >>> > + msleep(2500); > > >>> > + printk("DBG: good morning!\n"); > > >>> > + > > >>> > out: > > >>> > kfree_skb(skb); > > >>> > if (err) > > >>> > @@ -281,7 +288,7 @@ static int qca_inject_cmd_complete_event(struct > > >>> > hci_dev *hdev) > > >>> > > > >>> > evt = skb_put(skb, sizeof(*evt)); > > >>> > evt->ncmd = 1; > > >>> > - evt->opcode = HCI_OP_NOP; > > >>> > + evt->opcode = 0x42; > > >>> > > > >>> > skb_put_u8(skb, QCA_HCI_CC_SUCCESS); > > >>> > > > >>> > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c > > >>> > index f12555f23a49a0..c87ac1823439ab 100644 > > >>> > --- a/net/bluetooth/hci_event.c > > >>> > +++ b/net/bluetooth/hci_event.c > > >>> > @@ -3348,8 +3348,11 @@ static void hci_cmd_complete_evt(struct hci_dev > > >>> > *hdev, struct sk_buff *skb, > > >>> > break; > > >>> > } > > >>> > > > >>> > - if (*opcode != HCI_OP_NOP) > > >>> > + if (*opcode != HCI_OP_NOP) { > > >>> > + printk("DBG: cancelling command timer (opcode = 0x%02x)\n", > > >>> > + *opcode); > > >>> > cancel_delayed_work(&hdev->cmd_timer); > > >>> > + } > > >>> > > > >>> > if (ev->ncmd && !test_bit(HCI_RESET, &hdev->flags)) > > >>> > atomic_set(&hdev->cmd_cnt, 1); > > >>> > > > >>> > > > >>> > With that I see: > > >>> > > > >>> > [ 18.725417] Bluetooth: hci0: setting up wcn3990 > > >>> > [ 18.860381] DBG: ZZZzzzzzzz > > >>> > [ 18.863332] DBG: cancelling command timer (opcode = 0x42) > > >>> > [ 21.427085] DBG: good morning! > > >>> > > > >>> > > > >>> > The timer is clearly cancelled by the injected command (opcode 0x42) > > >>> > and no timeout occurs. I wouldn't expect you to see anything vastly > > >>> > different. > > >>> > > > >>> > Cheers > > >>> > > > >>> > Matthias > > >>> [Bala]: I think it would be better if we inject a command complete event > > >>> after we > > >>> receive the version data. instead of injecting in between firmware > > >>> download. > > >>> this change will be only for wcn3990. > > >> At first sight that doesn't sound like a bad idea if we want to inject > > >> a single command complete event. However the NVM download times out > > >> unless the command(s) of the TLV download is completed: > > >> [ 21.789452] Bluetooth: hci0: QCA Downloading qca/crnv21.bin > > >> [ 21.797675] Bluetooth: hci0: Send segment 0, size 243 > > >> [ 23.605597] Bluetooth: hci0: command 0xfc00 tx timeout > > >> So we should inject one command complete event after reading the SoC > > >> version and another after downloading the TLV file. An event after > > >> downloading the NVM file seems optional, since the HCI reset > > >> immediately after will cancel the timer anyway. > > >> Cheers > > >> Matthias > > > > > > [Bala]: sure will inject at cc event after the version command and also after the downloading TLV. > > > > I am still not convinced that this is all needed. Can not just wake > > up by waiting for the correct event. On the Intel side we actually > > wait for the firmware download event to come in before continuing. > > Without event injection at all we'd get timeout errors and > unnecessarily delay the firmware download, so I think at least this > part is needed in one way or the other. > > There are multiple options for where/when to inject the events. > > For reading the 'SoC version' I just learned that the controller > actually sends a command complete event, however the opcode is > HCI_OP_NOP, hence the command timer is not cancelled. > > Instead of just injecting the event after/at the end of > read_soc_version() I guess we could either forge the opcode in > qca_recv_frame() (to be created), or send the command to read the > version with __hci_cmd_sync() and inject the cmd complete event in > qca_dequeue(), analogously to what intel_dequeue() does. > > For the firmware download the same __hci_cmd_sync() + qca_dequeue() > approach could be used, however that would result in an injected event > for each FW segment, which we probably don't want. > IIUC Marcel suggests the QCA driver could do something similar to > intel_recv_event(), which detects a vendor specific event that > indicates that the firmware download is completed. I don't know if > there is such an event, Balakrishna might know. > > Marcel, is the above overall correct, and if so, do you have > preferences where multiple solutions exist? > > One doubt I have is if there is really much gain from the added > complexity in the described solutions, vs. just injecting the event as > done in Balakrishna's current patch, but I might be missing some > important details. > > Please bear with me if I got it all wrong, I'm learning about the > Bluetooth subsystem on the fly ;-) Marcel, please let us know what would be an acceptable solution for you. Thanks Matthias