From patchwork Fri Nov 29 12:19:15 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lee Jones X-Patchwork-Id: 21884 Return-Path: X-Original-To: linaro@patches.linaro.org Delivered-To: linaro@patches.linaro.org Received: from mail-oa0-f70.google.com (mail-oa0-f70.google.com [209.85.219.70]) by ip-10-151-82-157.ec2.internal (Postfix) with ESMTPS id C509923FEA for ; Fri, 29 Nov 2013 12:20:26 +0000 (UTC) Received: by mail-oa0-f70.google.com with SMTP id m1sf32493000oag.1 for ; Fri, 29 Nov 2013 04:20:26 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:delivered-to:from:to:cc:subject :date:message-id:in-reply-to:references:x-original-sender :x-original-authentication-results:precedence:mailing-list:list-id :list-post:list-help:list-archive:list-unsubscribe; bh=d2mBPQszT0BLxGgO2rldP2Fb9OPAYmXCeFmPLx2yETQ=; b=RRMMg6yv6RlMZ3+7a4i8TyEFL19uecQxfZ+dGEQ6JqmB9YYSjI9jzI0IUKoYhYsAiN HYiHa92gQxB0wOO8nRl4t7Y9sJ7SUUYTuZ9DINCjOnIudQ6NG54YF0NukfnOxEBXqL7Q Bu+n6UNRdZGX0YT3Fyt5riT2zfAghqtag16NLtRyCpq+khwjXuapX0udHeIw1J61ecJw HqOOFtbK65A0klW453hXjw/A8BeN8r+39+w5vV5Zuian0O4dwLsKAsVKUvQR3aiaFXBK ym5M4tW+rRxn6Z9+WNeQBoyZL7b61qE4OELKk3bijktb+xs+PFrrS+7RYXuSawPEzQfW GFbA== X-Gm-Message-State: ALoCoQlFWa6TTeTtUfraDcXd5K0/EAOZ4owwdYSvTwHY+keO0B5Qj3EFpPOPAhD5PcKFaPBY4K2+ X-Received: by 10.182.108.136 with SMTP id hk8mr16452625obb.11.1385727626390; Fri, 29 Nov 2013 04:20:26 -0800 (PST) MIME-Version: 1.0 X-BeenThere: patchwork-forward@linaro.org Received: by 10.49.12.11 with SMTP id u11ls3792271qeb.25.gmail; Fri, 29 Nov 2013 04:20:26 -0800 (PST) X-Received: by 10.220.16.73 with SMTP id n9mr1847876vca.24.1385727626311; Fri, 29 Nov 2013 04:20:26 -0800 (PST) Received: from mail-vb0-f48.google.com (mail-vb0-f48.google.com [209.85.212.48]) by mx.google.com with ESMTPS id g4si24769637vch.148.2013.11.29.04.20.26 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 29 Nov 2013 04:20:26 -0800 (PST) Received-SPF: neutral (google.com: 209.85.212.48 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) client-ip=209.85.212.48; Received: by mail-vb0-f48.google.com with SMTP id x16so6519983vbf.7 for ; Fri, 29 Nov 2013 04:20:26 -0800 (PST) X-Received: by 10.221.37.9 with SMTP id tc9mr1754123vcb.39.1385727626224; Fri, 29 Nov 2013 04:20:26 -0800 (PST) X-Forwarded-To: patchwork-forward@linaro.org X-Forwarded-For: patch@linaro.org patchwork-forward@linaro.org Delivered-To: patches@linaro.org Received: by 10.220.174.196 with SMTP id u4csp87452vcz; Fri, 29 Nov 2013 04:20:25 -0800 (PST) X-Received: by 10.236.85.97 with SMTP id t61mr43516900yhe.11.1385727625779; Fri, 29 Nov 2013 04:20:25 -0800 (PST) Received: from mail-yh0-f53.google.com (mail-yh0-f53.google.com [209.85.213.53]) by mx.google.com with ESMTPS id d70si4479339yhk.215.2013.11.29.04.20.25 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 29 Nov 2013 04:20:25 -0800 (PST) Received-SPF: neutral (google.com: 209.85.213.53 is neither permitted nor denied by best guess record for domain of lee.jones@linaro.org) client-ip=209.85.213.53; Received: by mail-yh0-f53.google.com with SMTP id b20so6606549yha.40 for ; Fri, 29 Nov 2013 04:20:25 -0800 (PST) X-Received: by 10.236.55.169 with SMTP id k29mr43987810yhc.23.1385727625560; Fri, 29 Nov 2013 04:20:25 -0800 (PST) Received: from localhost.localdomain (cpc15-aztw25-2-0-cust493.aztw.cable.virginm.net. [92.233.57.238]) by mx.google.com with ESMTPSA id m29sm101911689yho.14.2013.11.29.04.20.23 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 29 Nov 2013 04:20:25 -0800 (PST) From: Lee Jones To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, dwmw2@infradead.org Cc: linus.walleij@linaro.org, linux-mtd@lists.infradead.org, angus.clark@st.com, Lee Jones Subject: [PATCH v3 26/36] mtd: st_spi_fsm: Add the ability to read from a Serial Flash device Date: Fri, 29 Nov 2013 12:19:15 +0000 Message-Id: <1385727565-25794-27-git-send-email-lee.jones@linaro.org> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1385727565-25794-1-git-send-email-lee.jones@linaro.org> References: <1385727565-25794-1-git-send-email-lee.jones@linaro.org> X-Removed-Original-Auth: Dkim didn't pass. X-Original-Sender: lee.jones@linaro.org X-Original-Authentication-Results: mx.google.com; spf=neutral (google.com: 209.85.212.48 is neither permitted nor denied by best guess record for domain of patch+caf_=patchwork-forward=linaro.org@linaro.org) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org Precedence: list Mailing-list: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org List-ID: X-Google-Group-Id: 836684582541 List-Post: , List-Help: , List-Archive: List-Unsubscribe: , When a read is issued by userspace the MFD framework calls back into the driver to conduct the actual command issue and data extraction. Here we provide the routines which do exactly that. Signed-off-by: Lee Jones --- drivers/mtd/devices/st_spi_fsm.c | 110 +++++++++++++++++++++++++++++++++++++++ drivers/mtd/devices/st_spi_fsm.h | 3 ++ 2 files changed, 113 insertions(+) diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c index ad277f1..c76510e 100644 --- a/drivers/mtd/devices/st_spi_fsm.c +++ b/drivers/mtd/devices/st_spi_fsm.c @@ -538,6 +538,114 @@ static int stfsm_n25q_config(struct stfsm *fsm) return 0; } +static int stfsm_read(struct stfsm *fsm, uint8_t *const buf, + const uint32_t size, const uint32_t offset) +{ + struct stfsm_seq *seq = &stfsm_seq_read; + uint32_t data_pads; + uint32_t read_mask; + uint32_t size_ub; + uint32_t size_lb; + uint32_t size_mop; + uint32_t tmp[4]; + uint32_t page_buf[FLASH_PAGESIZE_32]; + uint8_t *p; + + dev_dbg(fsm->dev, "reading %d bytes from 0x%08x\n", size, offset); + + /* Enter 32-bit address mode, if required */ + if (fsm->configuration & CFG_READ_TOGGLE_32BIT_ADDR) + stfsm_enter_32bit_addr(fsm, 1); + + /* Must read in multiples of 32 cycles (or 32*pads/8 Bytes) */ + data_pads = ((seq->seq_cfg >> 16) & 0x3) + 1; + read_mask = (data_pads << 2) - 1; + + /* Handle non-aligned buf */ + p = ((uint32_t)buf & 0x3) ? (uint8_t *)page_buf : buf; + + /* Handle non-aligned size */ + size_ub = (size + read_mask) & ~read_mask; + size_lb = size & ~read_mask; + size_mop = size & read_mask; + + seq->data_size = TRANSFER_SIZE(size_ub); + seq->addr1 = (offset >> 16) & 0xffff; + seq->addr2 = offset & 0xffff; + + stfsm_load_seq(fsm, seq); + + if (size_lb) + stfsm_read_fifo(fsm, (uint32_t *)p, size_lb); + + if (size_mop) { + stfsm_read_fifo(fsm, tmp, read_mask + 1); + memcpy(p + size_lb, &tmp, size_mop); + } + + /* Handle non-aligned buf */ + if ((uint32_t)buf & 0x3) + memcpy(buf, page_buf, size); + + /* Wait for sequence to finish */ + stfsm_wait_seq(fsm); + + stfsm_clear_fifo(fsm); + + /* Exit 32-bit address mode, if required */ + if (fsm->configuration & CFG_READ_TOGGLE_32BIT_ADDR) + stfsm_enter_32bit_addr(fsm, 0); + + return 0; +} + +/* + * Read an address range from the flash chip. The address range + * may be any size provided it is within the physical boundaries. + */ +static int stfsm_mtd_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf) +{ + struct stfsm *fsm = dev_get_drvdata(mtd->dev.parent); + uint32_t bytes; + + dev_dbg(fsm->dev, "%s from 0x%08x, len %zd\n", + __func__, (u32)from, len); + + /* Initialise read length */ + if (retlen) + *retlen = 0; + + if (!len) { + dev_warn(fsm->dev, "Zero byte read requested\n"); + return 0; + } + + if (from + len > mtd->size) { + dev_err(fsm->dev, "Can't read past end of chip\n"); + return -EINVAL; + } + + mutex_lock(&fsm->lock); + + while (len > 0) { + bytes = min(len, (size_t)FLASH_PAGESIZE); + + stfsm_read(fsm, buf, bytes, from); + + buf += bytes; + from += bytes; + len -= bytes; + + if (retlen) + *retlen += bytes; + } + + mutex_unlock(&fsm->lock); + + return 0; +} + static void stfsm_read_jedec(struct stfsm *fsm, uint8_t *const jedec) { const struct stfsm_seq *seq = &stfsm_seq_read_jedec; @@ -806,6 +914,8 @@ static int stfsm_probe(struct platform_device *pdev) fsm->mtd.size = info->sector_size * info->n_sectors; fsm->mtd.erasesize = info->sector_size; + fsm->mtd._read = stfsm_mtd_read; + dev_err(&pdev->dev, "Found serial flash device: %s\n" " size = %llx (%lldMiB) erasesize = 0x%08x (%uKiB)\n", diff --git a/drivers/mtd/devices/st_spi_fsm.h b/drivers/mtd/devices/st_spi_fsm.h index b5ce07d..e168296 100644 --- a/drivers/mtd/devices/st_spi_fsm.h +++ b/drivers/mtd/devices/st_spi_fsm.h @@ -229,6 +229,9 @@ #define FLASH_CMD_READ4_1_1_4 0x6c #define FLASH_CMD_READ4_1_4_4 0xec +#define FLASH_PAGESIZE 256 /* In Bytes */ +#define FLASH_PAGESIZE_32 FLASH_PAGESIZE / 4 /* In uint32_t */ + /* * Flags to tweak operation of default read/write/erase routines */