From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752696AbcIIPk3 (ORCPT ); Fri, 9 Sep 2016 11:40:29 -0400 Received: from mout.kundenserver.de ([217.72.192.73]:51958 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751014AbcIIPk1 (ORCPT ); Fri, 9 Sep 2016 11:40:27 -0400 From: Arnd Bergmann To: Guenter Roeck Cc: Hoan Tran , Jean Delvare , Jonathan Corbet , Rob Herring , Jassi Brar , Ashwin Chaugule , Duc Dang , lho@apm.com, linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org Subject: [PATCH] hwmon: xgene: access mailbox as RAM Date: Fri, 09 Sep 2016 17:38:58 +0200 Message-ID: <2529114.aAikiSWl11@wuerfel> User-Agent: KMail/5.1.3 (Linux/4.4.0-34-generic; KDE/5.18.0; x86_64; ; ) In-Reply-To: <20160907223705.GA31582@roeck-us.net> References: <1469134557-26869-1-git-send-email-hotran@apm.com> <13081573.BbD3TmEU5Y@wuerfel> <20160907223705.GA31582@roeck-us.net> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:UePsGAFWnWnG7y03hAvk5PdHQRxV5nrjMx4wY8w6E2w8OfPaq38 5svfdmTUFGCzP3s2MvKxYGKdV7r6/1kiLEuoe18QVuYNdd8s9mm+BMOcIFoCgEXu7hyZDrP 0xMuXp+o9hYQ2NWAtAQpfpGH5Yaaj9M8PX/cOkw0myO1IJIgg9YAv8g0DzRnacjvKYlAxAo +z4CmYKLrRluhhDQu+/rA== X-UI-Out-Filterresults: notjunk:1;V01:K0:h3+W0S3xQvg=:GuXG2kUIqASprCxWuxxnT4 uKpG1+jGIcQUVVf/dWbZgEv/CuJNXlS6GwHX+RprsuXQISTaBClFZMIpV1onPhhcwyNyZgEta 9JGiZqz+z2V6349ALDNTvbfv2G40Q5Mm3BPf2HjbdwX+u2aivnNK3G7q/IkdJsXjyYxm+7/cq oqqsyDjoyNZlsSQK1PXjOW1ZPICX04izZkuZ6fSLYrXME1eJsYvW6H9F2YBUfe3oPi0mzfusg A4HXbCmMOu+bqz7DV/bEBITkXZ6/pHnmkkO6rGlDtAMNejoa6wPEmcMPWNmft5UxJGXrc2GbX qOH5JWMD9wPzIZA2GkqzpuK37QrbvJvEkwzKrTmVBzV1ICQzSmyr0oK53yuwxl5oxMy27omUc kRBMRv0Px+/+B6ONKZn3hYBLEuhnU4Q4iUB48Pgsls7GqkkTzuw5zLKGy8HGEp6NXhNsTqz8F AdOUmuKuD6kZrs3eHDgs/uc7PRHM+ArbeA0v6aY17/8BOyL3kGA4K83q4mCYa3CNRgHZ+dXfL rx9WlAe+EztVquAGpacIZZ0VL8f8eNfgPldjeffCRCXC16c/AjjQXxv1yUdl0q91LRPtJ9cKi 7sMUMMeiwfhHu9zHjSl9voPcPF9XFtXguAV+tz8GYbaJU1mCc7AeK8hOPZIAgT2H0WF6AjwBz QrIskX5TLhUbBifDq3oahjODn49ipJ1Yo1g9o9gvvyR6McYEGd2H+FJlAYVWT8wzG93A2DMDU WekSerH8sMCGgp4y Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The newly added hwmon driver fails to build in an allmodconfig kernel: 1 ERROR: "memblock_is_memory" [drivers/hwmon/xgene-hwmon.ko] undefined! According to comments in the code, the mailbox is a shared memory region, not a set of MMIO registers, so we should use memremap() for mapping it instead of ioremap or acpi_os_ioremap, and pointer dereferences instead of readl/writel. The driver already uses plain kernel pointers, so it's a bit unusual to work with functions that operate on __iomem pointers, and this fixes that part too. I'm using READ_ONCE/WRITE_ONCE here to keep the existing behavior regarding the ordering of the accesses from the CPU, but note that there are no barriers (also unchanged from before). I'm also keeping the endianess behavior, though I'm unsure whether the message data was supposed to be in LE32 format in the first place, it's possible this was meant to be interpreted as a byte stream instead. Signed-off-by: Arnd Bergmann diff --git a/drivers/hwmon/xgene-hwmon.c b/drivers/hwmon/xgene-hwmon.c index bc78a5d10182..e834dfb3acca 100644 --- a/drivers/hwmon/xgene-hwmon.c +++ b/drivers/hwmon/xgene-hwmon.c @@ -34,7 +34,8 @@ #include #include #include -#include +#include + #include /* SLIMpro message defines */ @@ -126,10 +127,10 @@ static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask) { u16 ret, val; - val = readw_relaxed(addr); + val = le16_to_cpu(READ_ONCE(*addr)); ret = val & mask; val &= ~mask; - writew_relaxed(val, addr); + WRITE_ONCE(*addr, cpu_to_le16(val)); return ret; } @@ -137,7 +138,7 @@ static u16 xgene_word_tst_and_clr(u16 *addr, u16 mask) static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg) { struct acpi_pcct_shared_memory *generic_comm_base = ctx->pcc_comm_addr; - void *ptr = generic_comm_base + 1; + u32 *ptr = (void*)(generic_comm_base + 1); int rc, i; u16 val; @@ -146,21 +147,21 @@ static int xgene_hwmon_pcc_rd(struct xgene_hwmon_dev *ctx, u32 *msg) ctx->resp_pending = true; /* Write signature for subspace */ - writel_relaxed(PCC_SIGNATURE_MASK | ctx->mbox_idx, - &generic_comm_base->signature); + WRITE_ONCE(generic_comm_base->signature, + cpu_to_le32(PCC_SIGNATURE_MASK | ctx->mbox_idx)); /* Write to the shared command region */ - writew_relaxed(MSG_TYPE(msg[0]) | PCCC_GENERATE_DB_INT, - &generic_comm_base->command); + WRITE_ONCE(generic_comm_base->command, + cpu_to_le16(MSG_TYPE(msg[0]) | PCCC_GENERATE_DB_INT)); /* Flip CMD COMPLETE bit */ - val = readw_relaxed(&generic_comm_base->status); + val = le16_to_cpu(READ_ONCE(generic_comm_base->status)); val &= ~PCCS_CMD_COMPLETE; - writew_relaxed(val, &generic_comm_base->status); + WRITE_ONCE(generic_comm_base->status, cpu_to_le16(val)); /* Copy the message to the PCC comm space */ for (i = 0; i < sizeof(struct slimpro_resp_msg) / 4; i++) - writel_relaxed(msg[i], ptr + i * 4); + WRITE_ONCE(ptr[i], cpu_to_le32(msg[i])); /* Ring the doorbell */ rc = mbox_send_message(ctx->mbox_chan, msg); @@ -652,9 +653,9 @@ static int xgene_hwmon_probe(struct platform_device *pdev) */ ctx->comm_base_addr = cppc_ss->base_address; if (ctx->comm_base_addr) { - ctx->pcc_comm_addr = - acpi_os_ioremap(ctx->comm_base_addr, - cppc_ss->length); + ctx->pcc_comm_addr = memremap(ctx->comm_base_addr, + cppc_ss->length, + MEMREMAP_WT); } else { dev_err(&pdev->dev, "Failed to get PCC comm region\n"); rc = -ENODEV;