From patchwork Tue Apr 2 20:27:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arseniy Krasnov X-Patchwork-Id: 13614587 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 89F9DCD1294 for ; Tue, 2 Apr 2024 20:38:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; 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Tue, 2 Apr 2024 23:37:42 +0300 From: Arseniy Krasnov To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Neil Armstrong , Kevin Hilman , Jerome Brunet , Martin Blumenstingl CC: , , , , , , , Arseniy Krasnov Subject: [PATCH v1 1/2] dt-bindings: mtd: amlogic,meson-nand: support fields for boot ROM code Date: Tue, 2 Apr 2024 23:27:04 +0300 Message-ID: <20240402202705.2355326-2-avkrasnov@salutedevices.com> X-Mailer: git-send-email 2.35.0 In-Reply-To: <20240402202705.2355326-1-avkrasnov@salutedevices.com> References: <20240402202705.2355326-1-avkrasnov@salutedevices.com> MIME-Version: 1.0 X-Originating-IP: [100.64.160.123] X-ClientProxiedBy: p-i-exch-sc-m01.sberdevices.ru (172.16.192.107) To p-i-exch-sc-m02.sberdevices.ru (172.16.192.103) X-KSMG-Rule-ID: 10 X-KSMG-Message-Action: clean X-KSMG-AntiSpam-Lua-Profiles: 184542 [Apr 02 2024] X-KSMG-AntiSpam-Version: 6.1.0.4 X-KSMG-AntiSpam-Envelope-From: avkrasnov@salutedevices.com X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Info: LuaCore: 14 0.3.14 5a0c43d8a1c3c0e5b0916cc02a90d4b950c01f96, {Tracking_from_domain_doesnt_match_to}, smtp.sberdevices.ru:7.1.1,5.0.1;127.0.0.199:7.1.2;salutedevices.com:7.1.1;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;100.64.160.123:7.1.2, FromAlignment: s, ApMailHostAddress: 100.64.160.123 X-MS-Exchange-Organization-SCL: -1 X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiPhishing: Clean X-KSMG-LinksScanning: Clean X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.0.1.6960, bases: 2024/04/02 18:05:00 #24580759 X-KSMG-AntiVirus-Status: Clean, skipped X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240402_133750_916008_4BAAA936 X-CRM114-Status: GOOD ( 12.89 ) X-BeenThere: linux-amlogic@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-amlogic" Errors-To: linux-amlogic-bounces+linux-amlogic=archiver.kernel.org@lists.infradead.org Boot ROM code on Meson requires that some pages on NAND must be written in special mode: "short" ECC mode where each block is 384 bytes and scrambling mode is on. Such pages located with the specified interval within specified offset. Both interval and offset are located in the device tree and used by driver if 'nand-is-boot-medium' is set for NAND chip. Signed-off-by: Arseniy Krasnov --- .../bindings/mtd/amlogic,meson-nand.yaml | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml b/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml index 57b6957c8415..f49819ee76b8 100644 --- a/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml +++ b/Documentation/devicetree/bindings/mtd/amlogic,meson-nand.yaml @@ -64,11 +64,27 @@ patternProperties: items: maximum: 0 + meson,boot-page-last: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + The NFC driver needs this information to select ECC + algorithms supported by the boot ROM. + Only used in combination with 'nand-is-boot-medium'. + + meson,boot-page-step: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + The NFC driver needs this information to select ECC + algorithms supported by the boot ROM. + Only used in combination with 'nand-is-boot-medium'. + unevaluatedProperties: false dependencies: nand-ecc-strength: [nand-ecc-step-size] nand-ecc-step-size: [nand-ecc-strength] + meson,boot-page-last: [nand-is-boot-medium] + meson,boot-page-step: [nand-is-boot-medium] required: From patchwork Tue Apr 2 20:27:05 2024 Content-Type: text/plain; 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Such pages located with the specified interval within specified offset. Both interval and offset are located in the device tree and used by driver if 'nand-is-boot-medium' is set for NAND chip. Signed-off-by: Arseniy Krasnov --- drivers/mtd/nand/raw/meson_nand.c | 88 +++++++++++++++++++++---------- 1 file changed, 59 insertions(+), 29 deletions(-) diff --git a/drivers/mtd/nand/raw/meson_nand.c b/drivers/mtd/nand/raw/meson_nand.c index 00ce0e5bb970..3f29dd28bd43 100644 --- a/drivers/mtd/nand/raw/meson_nand.c +++ b/drivers/mtd/nand/raw/meson_nand.c @@ -35,6 +35,7 @@ #define NFC_CMD_RB BIT(20) #define NFC_CMD_SCRAMBLER_ENABLE BIT(19) #define NFC_CMD_SCRAMBLER_DISABLE 0 +#define NFC_CMD_SHORTMODE_ENABLE 1 #define NFC_CMD_SHORTMODE_DISABLE 0 #define NFC_CMD_RB_INT BIT(14) #define NFC_CMD_RB_INT_NO_PIN ((0xb << 10) | BIT(18) | BIT(16)) @@ -78,6 +79,8 @@ #define DMA_DIR(dir) ((dir) ? NFC_CMD_N2M : NFC_CMD_M2N) #define DMA_ADDR_ALIGN 8 +#define NFC_SHORT_MODE_ECC_SZ 384 + #define ECC_CHECK_RETURN_FF (-1) #define NAND_CE0 (0xe << 10) @@ -125,6 +128,8 @@ struct meson_nfc_nand_chip { u32 twb; u32 tadl; u32 tbers_max; + u32 boot_page_last; + u32 boot_page_step; u32 bch_mode; u8 *data_buf; @@ -298,28 +303,49 @@ static void meson_nfc_cmd_seed(struct meson_nfc *nfc, u32 seed) nfc->reg_base + NFC_REG_CMD); } -static void meson_nfc_cmd_access(struct nand_chip *nand, int raw, bool dir, - int scrambler) +static int meson_nfc_page_is_boot(struct nand_chip *nand, int page) +{ + const struct meson_nfc_nand_chip *meson_chip = to_meson_nand(nand); + + return (nand->options & NAND_IS_BOOT_MEDIUM) && + !(page % meson_chip->boot_page_step) && + (page < meson_chip->boot_page_last); +} + +static void meson_nfc_cmd_access(struct nand_chip *nand, bool raw, bool dir, int page) { + const struct meson_nfc_nand_chip *meson_chip = to_meson_nand(nand); struct mtd_info *mtd = nand_to_mtd(nand); struct meson_nfc *nfc = nand_get_controller_data(mtd_to_nand(mtd)); - struct meson_nfc_nand_chip *meson_chip = to_meson_nand(nand); - u32 bch = meson_chip->bch_mode, cmd; int len = mtd->writesize, pagesize, pages; + int scrambler; + u32 cmd; - pagesize = nand->ecc.size; + if (nand->options & NAND_NEED_SCRAMBLING) + scrambler = NFC_CMD_SCRAMBLER_ENABLE; + else + scrambler = NFC_CMD_SCRAMBLER_DISABLE; if (raw) { len = mtd->writesize + mtd->oobsize; cmd = len | scrambler | DMA_DIR(dir); - writel(cmd, nfc->reg_base + NFC_REG_CMD); - return; - } + } else if (meson_nfc_page_is_boot(nand, page)) { + pagesize = NFC_SHORT_MODE_ECC_SZ >> 3; + pages = mtd->writesize / 512; + + scrambler = NFC_CMD_SCRAMBLER_ENABLE; + cmd = CMDRWGEN(DMA_DIR(dir), scrambler, NFC_ECC_BCH8_1K, + NFC_CMD_SHORTMODE_ENABLE, pagesize, pages); + } else { + pagesize = nand->ecc.size >> 3; + pages = len / nand->ecc.size; - pages = len / nand->ecc.size; + cmd = CMDRWGEN(DMA_DIR(dir), scrambler, meson_chip->bch_mode, + NFC_CMD_SHORTMODE_DISABLE, pagesize, pages); + } - cmd = CMDRWGEN(DMA_DIR(dir), scrambler, bch, - NFC_CMD_SHORTMODE_DISABLE, pagesize, pages); + if (scrambler == NFC_CMD_SCRAMBLER_ENABLE) + meson_nfc_cmd_seed(nfc, page); writel(cmd, nfc->reg_base + NFC_REG_CMD); } @@ -743,15 +769,7 @@ static int meson_nfc_write_page_sub(struct nand_chip *nand, if (ret) return ret; - if (nand->options & NAND_NEED_SCRAMBLING) { - meson_nfc_cmd_seed(nfc, page); - meson_nfc_cmd_access(nand, raw, DIRWRITE, - NFC_CMD_SCRAMBLER_ENABLE); - } else { - meson_nfc_cmd_access(nand, raw, DIRWRITE, - NFC_CMD_SCRAMBLER_DISABLE); - } - + meson_nfc_cmd_access(nand, raw, DIRWRITE, page); cmd = nfc->param.chip_select | NFC_CMD_CLE | NAND_CMD_PAGEPROG; writel(cmd, nfc->reg_base + NFC_REG_CMD); meson_nfc_queue_rb(nand, PSEC_TO_MSEC(sdr->tPROG_max), false); @@ -829,15 +847,7 @@ static int meson_nfc_read_page_sub(struct nand_chip *nand, if (ret) return ret; - if (nand->options & NAND_NEED_SCRAMBLING) { - meson_nfc_cmd_seed(nfc, page); - meson_nfc_cmd_access(nand, raw, DIRREAD, - NFC_CMD_SCRAMBLER_ENABLE); - } else { - meson_nfc_cmd_access(nand, raw, DIRREAD, - NFC_CMD_SCRAMBLER_DISABLE); - } - + meson_nfc_cmd_access(nand, raw, DIRREAD, page); ret = meson_nfc_wait_dma_finish(nfc); meson_nfc_check_ecc_pages_valid(nfc, nand, raw); @@ -1436,6 +1446,26 @@ meson_nfc_nand_chip_init(struct device *dev, if (ret) return ret; + if (nand->options & NAND_IS_BOOT_MEDIUM) { + ret = of_property_read_u32(np, "meson,boot-page-last", + &meson_chip->boot_page_last); + if (ret) { + dev_err(dev, "could not retrieve 'meson,boot-page-last' property: %d", + ret); + nand_cleanup(nand); + return ret; + } + + ret = of_property_read_u32(np, "meson,boot-page-step", + &meson_chip->boot_page_step); + if (ret) { + dev_err(dev, "could not retrieve 'meson,boot-page-step' property: %d", + ret); + nand_cleanup(nand); + return ret; + } + } + ret = mtd_device_register(mtd, NULL, 0); if (ret) { dev_err(dev, "failed to register MTD device: %d\n", ret);