From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 822822D600 for ; Mon, 6 Jan 2025 07:06:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736147209; cv=none; b=toPe7WF9onSUf1k44qj2YtdGb3U/lUta7Hg/s5Cims66DPhWcJKWW2FcOGH0YARgbbA7dXoikatMn/oGCPJ/bu625rW83+TMlg/6wf58vee+GbnYor3aGSvf6/MXHTGK4OHXcRCC7gtPrM2t2lURHxxAoozHRemszBPcqzP49YU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736147209; c=relaxed/simple; bh=GUbg4aHLMsWYLz+V2S0cTUSrElvUz3q0QODYrjL3220=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KL6qAi0+a6pS3Vsx3NLkJW9eDcPqTMke98gLU5Sxa03JBxCEpuptFXPDnl+7PzJm3fzF8d56jqQMNgyYZCg/ydLvZaIGYY+1+Bzsbf/kh5oDCjr7afjceG6ZcjQYAD9w9ZwJ9puaahlduN1keLgesbXBxllMKQ7yRcYni6JvhF0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Qy1Mmtmi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Qy1Mmtmi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D2CECC4CED6; Mon, 6 Jan 2025 07:06:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736147209; bh=GUbg4aHLMsWYLz+V2S0cTUSrElvUz3q0QODYrjL3220=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Qy1MmtmiBPY9w9So0482Q3UcMpRTnlayO5wpMEIa9Hw8iZGMTcwQUrsLy5KYnr+3g jhiTxaVVWn5RyQRfFIGRt/iQ63RUz7JoE7wSjkl7uvWgmXx4nfsh2OV7v3AF1Tn6Mb /gszSxZaeC8OcMzLzEF/uH5hFw7lJ56feM3nf34j8nD04aXn2ltxrazvfuvmXPsgSv +b7hKkMJ9oQb/4L0eg63VFG60CgGHGCnQ+xYObIJH06OPjYZ6UmmVNtcN0zGATUC+m g9m4YsagdFYy8aDwCXIzb2QChkzJBn+U3Ct/1dYlvNTKKoFi2ie8Yw9HtIJE4TEl27 MOGeMaWOGDd0A== Date: Mon, 6 Jan 2025 07:06:45 +0000 From: Tzung-Bi Shih To: Gwendal Grignou Cc: bleung@chromium.org, chrome-platform@lists.linux.dev, dustin@howett.net, ben@jubnut.com Subject: Re: [PATCH 2/2] platform/chrome: Add Support for direct EC register memory access Message-ID: References: <20250103001950.2868856-1-gwendal@chromium.org> <20250103001950.2868856-3-gwendal@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250103001950.2868856-3-gwendal@chromium.org> On Thu, Jan 02, 2025 at 04:19:50PM -0800, Gwendal Grignou wrote: > Able to communicate with the EC: > ``` > ectool version > ... > Build info: brtk-0.0.0-df0ad93+ 2024-12-13 19:25:55 elmo@396-a1a > ``` Not sure if I understand: does it originally intend to show EC firmware version (i.e. "RW version:")? > Coreboot must exposed the memory region: > ``` > cat /proc/iomem | grep GOOG0004 > fe0b0000-fe0bffff : GOOG0004:00 > ``` `grep GOOG0004 /proc/iomem`. > Can observe the commands flowing between AP and EC: > cd /sys/kernel/debug/tracing > echo 1 > events/cros_ec/enable > echo 1 > tracing_on > cat trace_pipe > kworker/7:0-51 [007] ..... 188.619393: cros_ec_request_start: version: 0, offset: 0, command: EC_CMD_CONSOLE_SNAPSHOT, outsize: 0, insize: 0 > kworker/7:0-51 [007] ..... 188.625656: cros_ec_request_done: version: 0, offset: 0, command: EC_CMD_CONSOLE_SNAPSHOT, outsize: 0, insize: 0, ec result: EC_RES_SUCCESS, retval: 0 > kworker/7:0-51 [007] ..... 188.625663: cros_ec_request_start: version: 1, offset: 0, command: EC_CMD_CONSOLE_READ, outsize: 1, insize: 248 > kworker/7:0-51 [007] ..... 188.635119: cros_ec_request_done: version: 1, offset: 0, command: EC_CMD_CONSOLE_READ, outsize: 1, insize: 248, ec result: EC_RES_SUCCESS, retval: 147 > kworker/7:0-51 [007] ..... 188.635130: cros_ec_request_start: version: 1, offset: 0, command: EC_CMD_CONSOLE_READ, outsize: 1, insize: 248 > kworker/7:0-51 [007] ..... 188.642764: cros_ec_request_done: version: 1, offset: 0, command: EC_CMD_CONSOLE_READ, outsize: 1, insize: 248, ec result: EC_RES_SUCCESS, retval: 0 > timberslide-3755 [005] ..... 188.643039: cros_ec_request_start: version: 0, offset: 0, command: EC_CMD_GET_UPTIME_INFO, outsize: 0, insize: 44 > timberslide-3755 [006] ..... 188.650876: cros_ec_request_done: version: 0, offset: 0, command: EC_CMD_GET_UPTIME_INFO, outsize: 0, insize: 44, ec result: EC_RES_SUCCESS, retval: 44 > timberslide-3755 [006] ..... 188.650912: cros_ec_request_start: version: 0, offset: 0, command: EC_CMD_GET_UPTIME_INFO, outsize: 0, insize: 44 > timberslide-3755 [006] ..... 188.657907: cros_ec_request_done: version: 0, offset: 0, command: EC_CMD_GET_UPTIME_INFO, outsize: 0, insize: 44, ec result: EC_RES_SUCCESS, retval: 44 > kworker/7:0-51 [007] ..... 198.858864: cros_ec_request_start: version: 0, offset: 0, command: EC_CMD_CONSOLE_SNAPSHOT, outsize: 0, insize: 0 > kworker/7:0-51 [007] ..... 198.866866: cros_ec_request_done: version: 0, offset: 0, command: EC_CMD_CONSOLE_SNAPSHOT, outsize: 0, insize: 0, ec result: EC_RES_SUCCESS, retval: 0 > kworker/7:0-51 [007] ..... 198.866882: cros_ec_request_start: version: 1, offset: 0, command: EC_CMD_CONSOLE_READ, outsize: 1, insize: 248 > kworker/7:0-51 [007] ..... 198.874414: cros_ec_request_done: version: 1, offset: 0, command: EC_CMD_CONSOLE_READ, outsize: 1, insize: 248, ec result: EC_RES_SUCCESS, retval: 0 Can't it observe the trace before applying the patch? I failed to connect the trace and the direct memory accesses. On a related note, the patch should use prefix "cros_ec_lpc" too. > +static int cros_ec_lpc_direct_read(struct cros_ec_lpc *ec_lpc, unsigned int offset, > + unsigned int length, u8 *dest) > +{ [...] > + // Check range To be consitent to the rest of code, don't use C99 comment style. Or just drop it as the intent is clear. > +static int cros_ec_lpc_direct_write(struct cros_ec_lpc *ec_lpc, unsigned int offset, > + unsigned int length, const u8 *msg) > +{ [...] > + // Check range Same here. > +static acpi_status cros_ec_lpc_resources(struct acpi_resource *res, void *data) > +{ > + struct cros_ec_lpc *ec_lpc = data; > + > + switch (res->type) { > + case ACPI_RESOURCE_TYPE_FIXED_MEMORY32: > + ec_lpc->mem32 = res->data.fixed_memory32; > + break; > + case ACPI_RESOURCE_TYPE_EXTENDED_IRQ: > + /* Ignored, using a more generic way to find IRQ. */ > + case ACPI_RESOURCE_TYPE_END_TAG: If nothing to do (or comment) in the case, could it drop the case? > @@ -498,29 +560,52 @@ static int cros_ec_lpc_probe(struct platform_device *pdev) [...] > + if (ec_lpc->mem32.address_length) { > + ec_lpc->base = devm_ioremap(dev, > + ec_lpc->mem32.address, > + ec_lpc->mem32.address_length); > + if (IS_ERR(ec_lpc->base)) > + return AE_ERROR; `PTR_ERR(...)`?