From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fllv0015.ext.ti.com (fllv0015.ext.ti.com [198.47.19.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A778F8F72; Fri, 21 Jun 2024 13:46:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.47.19.141 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718977599; cv=none; b=rh00PfvKIoovc6nk7ocbtz8pa2oiYyv2D6G2gLMTJJ+FuzEl8O8uN/Md8pVrLiaQ0HBMtAwwVrRf5UDnDLnB0UmEiujzmH3vLS3sCGyBU230frPF3vwUqjGc1qEO0AkuoFmOoyg0h4QZQ0JoI9FRAALCM5cyoaiKZWfCa65K2pc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718977599; c=relaxed/simple; bh=2iE87/L+OfdgoYD5w2DmZlkdnKlm/H8czLLfTMuSRx8=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=R4XLS51eBEt7a+1FmLrhP0+txFtLYdQbngNEjGyA66AiNvTuFfQGkRQJ1d0IdjisE+IE4p8QTWeZOBB8FD6rVmJsRfHwGEgA8rWOuRTVEWtHWHLuDqi4WS7KdSg1RQvcbrXFj0YkHLvWW6dVa4/z/PD2nsut9cuSnek9Vc6UBjY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com; spf=pass smtp.mailfrom=ti.com; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b=mcLaDXZG; arc=none smtp.client-ip=198.47.19.141 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ti.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ti.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="mcLaDXZG" Received: from fllv0035.itg.ti.com ([10.64.41.0]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 45LDkTSS002408; Fri, 21 Jun 2024 08:46:29 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1718977589; bh=ObWfyBQB8BEp+dUAGvv0hDtX2HOAYVLCcFkDZ547bu0=; h=Date:Subject:To:CC:References:From:In-Reply-To; b=mcLaDXZGh0b4dX/BSjCnZjtQ2KqiuEXhLhKoxlqJG06gaE9V8CDj+T7ZNGDvNwjj1 6abNBUpL4xbWi3xXtdKBcew3WjHc9xuTb4o5IKaf6s7eZ6WbbV5Efy/4atlqPwQ+j0 OoyQmKrxmNm3GX0xpi3+SVRJvpN267Kv1eibLY78= Received: from DLEE115.ent.ti.com (dlee115.ent.ti.com [157.170.170.26]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 45LDkTPk096537 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 21 Jun 2024 08:46:29 -0500 Received: from DLEE101.ent.ti.com (157.170.170.31) by DLEE115.ent.ti.com (157.170.170.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Fri, 21 Jun 2024 08:46:28 -0500 Received: from lelvsmtp5.itg.ti.com (10.180.75.250) by DLEE101.ent.ti.com (157.170.170.31) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Fri, 21 Jun 2024 08:46:28 -0500 Received: from [128.247.81.8] (ula0226330.dhcp.ti.com [128.247.81.8] (may be forged)) by lelvsmtp5.itg.ti.com (8.15.2/8.15.2) with ESMTP id 45LDkSvc059976; Fri, 21 Jun 2024 08:46:28 -0500 Message-ID: Date: Fri, 21 Jun 2024 08:46:28 -0500 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/3] remoteproc: k3-r5: Acquire mailbox handle during probe To: Beleswar Prasad Padhi , , CC: , , , References: <20240604051722.3608750-1-b-padhi@ti.com> <20240604051722.3608750-3-b-padhi@ti.com> Content-Language: en-US From: Andrew Davis In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 On 6/21/24 6:14 AM, Beleswar Prasad Padhi wrote: > Hi Andrew, > > On 04/06/24 22:40, Andrew Davis wrote: >> On 6/4/24 12:17 AM, Beleswar Padhi wrote: >>> Acquire the mailbox handle during device probe and do not release handle >>> in stop/detach routine or error paths. This removes the redundant >>> requests for mbox handle later during rproc start/attach. This also >>> allows to defer remoteproc driver's probe if mailbox is not probed yet. >>> >>> Signed-off-by: Beleswar Padhi >>> --- >>>   drivers/remoteproc/ti_k3_r5_remoteproc.c | 74 +++++++++--------------- >>>   1 file changed, 26 insertions(+), 48 deletions(-) >>> >>> diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c b/drivers/remoteproc/ti_k3_r5_remoteproc.c >>> index 26362a509ae3c..7e02e3472ce25 100644 >>> --- a/drivers/remoteproc/ti_k3_r5_remoteproc.c >>> +++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c >>> @@ -194,6 +194,10 @@ static void k3_r5_rproc_mbox_callback(struct mbox_client *client, void *data) >>>       const char *name = kproc->rproc->name; >>>       u32 msg = omap_mbox_message(data); >>>   +    /* Do not forward message to a detached core */ >> >> s/to/from >> >> This is the receive side from the core. >> >>> +    if (kproc->rproc->state == RPROC_DETACHED) >>> +        return; >>> + >> >> Do we need a similar check when sending messages to the core in >> k3_r5_rproc_kick()? No one should be sending anything as they >> all should have detached at this point, but something to double >> check on. > Will add this in the next revision. >> >>>       dev_dbg(dev, "mbox msg: 0x%x\n", msg); >>>         switch (msg) { >>> @@ -399,12 +403,9 @@ static int k3_r5_rproc_request_mbox(struct rproc *rproc) >>>       client->knows_txdone = false; >>>         kproc->mbox = mbox_request_channel(client, 0); >>> -    if (IS_ERR(kproc->mbox)) { >>> -        ret = -EBUSY; >>> -        dev_err(dev, "mbox_request_channel failed: %ld\n", >>> -            PTR_ERR(kproc->mbox)); >>> -        return ret; >>> -    } >>> +    if (IS_ERR(kproc->mbox)) >>> +        return dev_err_probe(dev, PTR_ERR(kproc->mbox), >>> +                     "mbox_request_channel failed\n"); >> >> This is good cleanup, but maybe something for its own patch. > I think this cleanup is dependent to this patch itself. The current patch moves the mbox_handle_request to probe routine. And the cleanup returns an -EDEFER_PROBE ERR code. So, this cleanup is only valid if the current patch is applied. Else, if this err code is returned at any point after creation of child devices, it could lead to a infinite loop[0]. Please correct me if I am wrong..? > Okay I see what you are saying, k3_r5_rproc_request_mbox() is now called from probe() and not start() as it was before. Then you are correct. Andrew > [0]: https://www.kernel.org/doc/html/v6.5-rc3/driver-api/driver-model/driver.html#callbacks >> >>>         /* >>>        * Ping the remote processor, this is only for sanity-sake for now; >>> @@ -552,10 +553,6 @@ static int k3_r5_rproc_start(struct rproc *rproc) >>>       u32 boot_addr; >>>       int ret; >>>   -    ret = k3_r5_rproc_request_mbox(rproc); >>> -    if (ret) >>> -        return ret; >>> - >>>       boot_addr = rproc->bootaddr; >>>       /* TODO: add boot_addr sanity checking */ >>>       dev_dbg(dev, "booting R5F core using boot addr = 0x%x\n", boot_addr); >>> @@ -564,7 +561,7 @@ static int k3_r5_rproc_start(struct rproc *rproc) >>>       core = kproc->core; >>>       ret = ti_sci_proc_set_config(core->tsp, boot_addr, 0, 0); >>>       if (ret) >>> -        goto put_mbox; >>> +        return ret; >>>         /* unhalt/run all applicable cores */ >>>       if (cluster->mode == CLUSTER_MODE_LOCKSTEP) { >>> @@ -580,13 +577,12 @@ static int k3_r5_rproc_start(struct rproc *rproc) >>>           if (core != core0 && core0->rproc->state == RPROC_OFFLINE) { >>>               dev_err(dev, "%s: can not start core 1 before core 0\n", >>>                   __func__); >>> -            ret = -EPERM; >>> -            goto put_mbox; >>> +            return -EPERM; >>>           } >>>             ret = k3_r5_core_run(core); >>>           if (ret) >>> -            goto put_mbox; >>> +            return ret; >>>       } >>>         return 0; >>> @@ -596,8 +592,6 @@ static int k3_r5_rproc_start(struct rproc *rproc) >>>           if (k3_r5_core_halt(core)) >>>               dev_warn(core->dev, "core halt back failed\n"); >>>       } >>> -put_mbox: >>> -    mbox_free_channel(kproc->mbox); >>>       return ret; >>>   } >>>   @@ -658,8 +652,6 @@ static int k3_r5_rproc_stop(struct rproc *rproc) >>>               goto out; >>>       } >>>   -    mbox_free_channel(kproc->mbox); >>> - >>>       return 0; >>>     unroll_core_halt: >>> @@ -674,42 +666,22 @@ static int k3_r5_rproc_stop(struct rproc *rproc) >>>   /* >>>    * Attach to a running R5F remote processor (IPC-only mode) >>>    * >>> - * The R5F attach callback only needs to request the mailbox, the remote >>> - * processor is already booted, so there is no need to issue any TI-SCI >>> - * commands to boot the R5F cores in IPC-only mode. This callback is invoked >>> - * only in IPC-only mode. >>> + * The R5F attach callback is a NOP. The remote processor is already booted, and >>> + * all required resources have been acquired during probe routine, so there is >>> + * no need to issue any TI-SCI commands to boot the R5F cores in IPC-only mode. >>> + * This callback is invoked only in IPC-only mode and exists because >>> + * rproc_validate() checks for its existence. >>>    */ >>> -static int k3_r5_rproc_attach(struct rproc *rproc) >>> -{ >>> -    struct k3_r5_rproc *kproc = rproc->priv; >>> -    struct device *dev = kproc->dev; >>> -    int ret; >>> - >>> -    ret = k3_r5_rproc_request_mbox(rproc); >>> -    if (ret) >>> -        return ret; >>> - >>> -    dev_info(dev, "R5F core initialized in IPC-only mode\n"); >>> -    return 0; >>> -} >>> +static int k3_r5_rproc_attach(struct rproc *rproc) { return 0; } >> >> I wonder if rproc_validate() should be updated to allow not >> having an attach/detach for cases like this. Then we could drop >> this function completely. >> >> Andrew >> >>>     /* >>>    * Detach from a running R5F remote processor (IPC-only mode) >>>    * >>> - * The R5F detach callback performs the opposite operation to attach callback >>> - * and only needs to release the mailbox, the R5F cores are not stopped and >>> - * will be left in booted state in IPC-only mode. This callback is invoked >>> - * only in IPC-only mode. >>> + * The R5F detach callback is a NOP. The R5F cores are not stopped and will be >>> + * left in booted state in IPC-only mode. This callback is invoked only in >>> + * IPC-only mode and exists for sanity sake. >>>    */ >>> -static int k3_r5_rproc_detach(struct rproc *rproc) >>> -{ >>> -    struct k3_r5_rproc *kproc = rproc->priv; >>> -    struct device *dev = kproc->dev; >>> - >>> -    mbox_free_channel(kproc->mbox); >>> -    dev_info(dev, "R5F core deinitialized in IPC-only mode\n"); >>> -    return 0; >>> -} >>> +static int k3_r5_rproc_detach(struct rproc *rproc) { return 0; } >>>     /* >>>    * This function implements the .get_loaded_rsc_table() callback and is used >>> @@ -1277,6 +1249,10 @@ static int k3_r5_cluster_rproc_init(struct platform_device *pdev) >>>           kproc->rproc = rproc; >>>           core->rproc = rproc; >>>   +        ret = k3_r5_rproc_request_mbox(rproc); >>> +        if (ret) >>> +            return ret; >>> + >>>           ret = k3_r5_rproc_configure_mode(kproc); >>>           if (ret < 0) >>>               goto err_config; >>> @@ -1393,6 +1369,8 @@ static void k3_r5_cluster_rproc_exit(void *data) >>>               } >>>           } >>>   +        mbox_free_channel(kproc->mbox); >>> + >>>           rproc_del(rproc); >>>             k3_r5_reserved_mem_exit(kproc);