From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965597AbdDSQKP (ORCPT ); Wed, 19 Apr 2017 12:10:15 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:33774 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965436AbdDSQJE (ORCPT ); Wed, 19 Apr 2017 12:09:04 -0400 Subject: Re: [PATCH v3 5/6] mtd: dataflash: Make use of "extened device information" To: Andrey Smirnov References: <20170419152305.17226-1-andrew.smirnov@gmail.com> <20170419152305.17226-5-andrew.smirnov@gmail.com> Cc: linux-mtd@lists.infradead.org, Chris Healy , David Woodhouse , Brian Norris , Boris Brezillon , Richard Weinberger , Cyrille Pitchen , linux-kernel From: Marek Vasut Message-ID: Date: Wed, 19 Apr 2017 18:08:59 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.4.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/19/2017 06:01 PM, Andrey Smirnov wrote: > On Wed, Apr 19, 2017 at 8:42 AM, Marek Vasut wrote: >> On 04/19/2017 05:23 PM, Andrey Smirnov wrote: >>> In anticipation of supporting chips that need it, extend the size of >>> struct flash_info's 'jedec_id' field to make room 2 byte of extended >>> device information as well as add code to fetch this data during >>> jedec_probe(). >>> >>> Cc: cphealy@gmail.com >>> Cc: David Woodhouse >>> Cc: Brian Norris >>> Cc: Boris Brezillon >>> Cc: Marek Vasut >>> Cc: Richard Weinberger >>> Cc: Cyrille Pitchen >>> Cc: linux-kernel@vger.kernel.org >>> Signed-off-by: Andrey Smirnov >>> --- >>> >>> Changes since [v2]: >>> >>> - Make 'id' have same size as 'jedec' >>> >>> - Get rid of eid_mask variable in favour of using GENMASK >>> in-place >>> >>> Changes since [v1]: >>> >>> - Formatting >>> >>> [v1] http://lkml.kernel.org/r/20170411161722.11164-1-andrew.smirnov@gmail.com >>> [v2] http://lkml.kernel.org/r/20170418142127.23301-3-andrew.smirnov@gmail.com >>> >>> drivers/mtd/devices/mtd_dataflash.c | 115 +++++++++++++++++++++--------------- >>> 1 file changed, 68 insertions(+), 47 deletions(-) >>> >>> diff --git a/drivers/mtd/devices/mtd_dataflash.c b/drivers/mtd/devices/mtd_dataflash.c >>> index 2d3e403..941e8b7 100644 >>> --- a/drivers/mtd/devices/mtd_dataflash.c >>> +++ b/drivers/mtd/devices/mtd_dataflash.c >>> @@ -687,7 +687,7 @@ struct flash_info { >>> /* JEDEC id has a high byte of zero plus three data bytes: >>> * the manufacturer id, then a two byte device id. >>> */ >>> - u32 jedec_id; >>> + u64 jedec_id; >>> >>> /* The size listed here is what works with OP_ERASE_PAGE. */ >>> unsigned nr_pages; >>> @@ -710,62 +710,34 @@ static struct flash_info dataflash_data[] = { >>> * These newer chips also support 128-byte security registers (with >>> * 64 bytes one-time-programmable) and software write-protection. >>> */ >>> - { "AT45DB011B", 0x1f2200, 512, 264, 9, SUP_POW2PS}, >>> - { "at45db011d", 0x1f2200, 512, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB011B", 0x1f22000000, 512, 264, 9, SUP_POW2PS}, >>> + { "at45db011d", 0x1f22000000, 512, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> >>> - { "AT45DB021B", 0x1f2300, 1024, 264, 9, SUP_POW2PS}, >>> - { "at45db021d", 0x1f2300, 1024, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB021B", 0x1f23000000, 1024, 264, 9, SUP_POW2PS}, >>> + { "at45db021d", 0x1f23000000, 1024, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> >>> - { "AT45DB041x", 0x1f2400, 2048, 264, 9, SUP_POW2PS}, >>> - { "at45db041d", 0x1f2400, 2048, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB041x", 0x1f24000000, 2048, 264, 9, SUP_POW2PS}, >>> + { "at45db041d", 0x1f24000000, 2048, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> >>> - { "AT45DB081B", 0x1f2500, 4096, 264, 9, SUP_POW2PS}, >>> - { "at45db081d", 0x1f2500, 4096, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB081B", 0x1f25000000, 4096, 264, 9, SUP_POW2PS}, >>> + { "at45db081d", 0x1f25000000, 4096, 256, 8, SUP_POW2PS | IS_POW2PS}, >>> >>> - { "AT45DB161x", 0x1f2600, 4096, 528, 10, SUP_POW2PS}, >>> - { "at45db161d", 0x1f2600, 4096, 512, 9, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB161x", 0x1f26000000, 4096, 528, 10, SUP_POW2PS}, >>> + { "at45db161d", 0x1f26000000, 4096, 512, 9, SUP_POW2PS | IS_POW2PS}, >>> >>> - { "AT45DB321x", 0x1f2700, 8192, 528, 10, 0}, /* rev C */ >>> + { "AT45DB321x", 0x1f27000000, 8192, 528, 10, 0}, /* rev C */ >>> >>> - { "AT45DB321x", 0x1f2701, 8192, 528, 10, SUP_POW2PS}, >>> - { "at45db321d", 0x1f2701, 8192, 512, 9, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB321x", 0x1f27010000, 8192, 528, 10, SUP_POW2PS}, >>> + { "at45db321d", 0x1f27010000, 8192, 512, 9, SUP_POW2PS | IS_POW2PS}, >>> >>> - { "AT45DB642x", 0x1f2800, 8192, 1056, 11, SUP_POW2PS}, >>> - { "at45db642d", 0x1f2800, 8192, 1024, 10, SUP_POW2PS | IS_POW2PS}, >>> + { "AT45DB642x", 0x1f28000000, 8192, 1056, 11, SUP_POW2PS}, >>> + { "at45db642d", 0x1f28000000, 8192, 1024, 10, SUP_POW2PS | IS_POW2PS}, >>> }; >>> >>> -static struct flash_info *jedec_probe(struct spi_device *spi) >>> +static struct flash_info *jedec_lookup(struct spi_device *spi, u64 jedec) >>> { >>> - int ret; >>> - u8 code = OP_READ_ID; >>> - u8 id[3]; >>> - u32 jedec; >>> - struct flash_info *info; >>> int status; >>> - >>> - /* >>> - * JEDEC also defines an optional "extended device information" >>> - * string for after vendor-specific data, after the three bytes >>> - * we use here. Supporting some chips might require using it. >>> - * >>> - * If the vendor ID isn't Atmel's (0x1f), assume this call failed. >>> - * That's not an error; only rev C and newer chips handle it, and >>> - * only Atmel sells these chips. >>> - */ >>> - ret = spi_write_then_read(spi, &code, 1, id, 3); >>> - if (ret < 0) { >>> - dev_dbg(&spi->dev, "error %d reading JEDEC ID\n", ret); >>> - return ERR_PTR(ret); >>> - } >>> - >>> - if (id[0] != CFI_MFR_ATMEL) >>> - return NULL; >>> - >>> - jedec = id[0]; >>> - jedec = jedec << 8; >>> - jedec |= id[1]; >>> - jedec = jedec << 8; >>> - jedec |= id[2]; >>> + struct flash_info *info; >>> >>> for (info = dataflash_data; >>> info < dataflash_data + ARRAY_SIZE(dataflash_data); >>> @@ -793,12 +765,61 @@ static struct flash_info *jedec_probe(struct spi_device *spi) >>> } >>> } >>> >>> + return NULL; >>> +} >>> + >>> +static struct flash_info *jedec_probe(struct spi_device *spi) >>> +{ >>> + int ret; >>> + u8 code = OP_READ_ID; >>> + u64 jedec; >>> + u8 id[sizeof(jedec)] = {0}; >>> + const unsigned int id_size = 5; >>> + const unsigned int first_byte = sizeof(id) - id_size; >>> + struct flash_info *info; >>> + >>> + /* >>> + * JEDEC also defines an optional "extended device information" >>> + * string for after vendor-specific data, after the three bytes >>> + * we use here. Supporting some chips might require using it. >>> + * >>> + * If the vendor ID isn't Atmel's (0x1f), assume this call failed. >>> + * That's not an error; only rev C and newer chips handle it, and >>> + * only Atmel sells these chips. >>> + */ >>> + ret = spi_write_then_read(spi, &code, 1, &id[first_byte], id_size); >> >> Hm, looking at this again, what prevents you from reading these bytes >> into &id[0] ? Might be easier, ie. >> >> ret = spi_write_then_read(spi, &code, 1, id, id_size); >> > > Then I'd have to add 6 more '0's to each of the IDs in dataflash_data, > which would make that code even less readable. Or do >>= 24 on the jedec ID :) >>> + if (ret < 0) { >>> + pr_debug("%s: error %d reading JEDEC ID\n", >>> + dev_name(&spi->dev), ret); >>> + return ERR_PTR(ret); >>> + } >>> + >>> + if (id[first_byte] != CFI_MFR_ATMEL) >> >> if (id[0] != CFI_MFR_ATMEL) >> >>> + return NULL; >>> + >>> + jedec = be64_to_cpup((__be64 *)id); >>> + >>> + info = jedec_lookup(spi, jedec); >> >> ... define these somewhere at the beginning of the dataflash code ... >> #define DATAFLASH_MASK_STD GENMASK(63, 40) >> #define DATAFLASH_MASK_EXT GENMASK(63, 16) >> >> ... then ... >> info = jedec_lookup(spi, jedec & DATAFLASH_MASK_EXT); >> >>> + if (info) >>> + return info; >>> + >>> + /* >>> + * Clear extended id bits (bits 0 through 15) and try to find >>> + * a match again in case our chip does not support returning >>> + * extended ID information and we got invalid bits instead >>> + */ >>> + jedec &= GENMASK_ULL(63, 16); >> >> info = jedec_lookup(spi, jedec & DATAFLASH_MASK_STD); >> > > Sure, OK. > > Thanks, > Andrey Smirnov > -- Best regards, Marek Vasut