From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 04 Mar 2026 12:44:27 +0100 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vxkeQ-007yDv-35 for lore@lore.pengutronix.de; Wed, 04 Mar 2026 12:44:27 +0100 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1vxkeQ-0006tz-SP for lore@pengutronix.de; Wed, 04 Mar 2026 12:44:27 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=9OX+RQRdLgJwcOIiI/fkCSApZdT4CiLLlzfSJiuMjhE=; b=OwpidTbkDAaZXR3v6sWWKeCosv 2kblrnTa6RPLi1VdTgJ3njv4s2w0G4H9KwGwr/TefByRXczii8Bt5xmHP5lOdcigz92s6tFM055uy Bv/4ke+xVcKcVh7Ph8TXk1xi2+fWyd4R1NIOdJ0a/tJ/roJtwswH2w87nizC/R55dtdB1PRdPHZn5 W+wK0Fv58OrJV1N+KugFmPq15FhZihnWwIGdzOR7FkH7IubI2SWUNYOZeBj4dzuEO7Iy2CvnVN6H4 t8r4hQETZ5LSDIlFX1LR7w38Ni3xiLQVd9bXiwMlIG5S4Q+K+wXjRvXs2+IbYbfRcN7w2gRFM52N1 H3DZMoNQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vxkdz-0000000H7oh-2z1Y; Wed, 04 Mar 2026 11:43:59 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vxkdx-0000000H7ne-1hqe for barebox@lists.infradead.org; Wed, 04 Mar 2026 11:43:58 +0000 Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=[127.0.0.1]) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1vxkdv-0006lj-P7; Wed, 04 Mar 2026 12:43:55 +0100 Message-ID: <18ef490b-4b99-49f9-89d1-9ce2d346d4a4@pengutronix.de> Date: Wed, 4 Mar 2026 12:43:55 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird To: Steffen Trumtrar , barebox@lists.infradead.org, Sascha Hauer Cc: David Jander References: <20260304-v2026-02-0-topic-imx8-ecc-v1-0-700698530c5c@pengutronix.de> <20260304-v2026-02-0-topic-imx8-ecc-v1-3-700698530c5c@pengutronix.de> Content-Language: en-US, de-DE, de-BE From: Ahmad Fatoum In-Reply-To: <20260304-v2026-02-0-topic-imx8-ecc-v1-3-700698530c5c@pengutronix.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260304_034357_599951_3DF1217D X-CRM114-Status: GOOD ( 29.15 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.whiteo.stw.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-3.8 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: Re: [PATCH 3/4] drivers: ddr: imx8m: ddr_init.c: support ECC scrubbing X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.whiteo.stw.pengutronix.de) Hi, On 3/4/26 12:23 PM, Steffen Trumtrar wrote: > From: David Jander > > This code comes from u-boot [1] and was introducesd in commit [2]. > > A fix from the patch [3] is also included, which doesn't seem to be > added to u-boot, yet. > > [1] https://github.com/u-boot/u-boot/ > [2] commit f3acb02386f4 ("drivers: ddr: imx8mp: Add inline ECC feature support") > [3] https://patchwork.ozlabs.org/project/uboot/patch/20230123091702.7472-32-peng.fan@oss.nxp.com/ > > Signed-off-by: David Jander > Signed-off-by: Steffen Trumtrar > --- > arch/arm/mach-imx/Kconfig | 8 +++++ > drivers/ddr/imx/imx8m_ddr_init.c | 73 ++++++++++++++++++++++++++++++++++++++++ > include/soc/imx8m/ddr.h | 11 ++++++ > 3 files changed, 92 insertions(+) > > diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig > index d244c57580..75b04cf70f 100644 > --- a/arch/arm/mach-imx/Kconfig > +++ b/arch/arm/mach-imx/Kconfig > @@ -1026,6 +1026,14 @@ config HABV3_IMG_CRT_DER > > endif > > +config IMX8MP_DRAM_ECC > + bool "Enable LPDDR4 ECC feature on i.MX8MP boards" > + depends on ARCH_IMX8MP > + help > + The i.MX8MP SoC supports ECC on the LPDDR4 memory. Select Y to enable > + this feature. The total amount of memory available will be reduced by > + 1/8th. A generic option is too confusing when it's only affecting a single board. Alternative suggestion: - make IMX8MP_DRAM_ECC a hidden symbol - select it from the protonic board - Turn the RAM timings of the protonic board into a header and replace #ifdef CONFIG_IMX8MP_DRAM_ECC with #ifdef USE_ECC - Add two source code files, that include the new header once with USE_ECC supported and once without - Add two entry points which only differ in what RAM timings are used Also worth considering: adding the size of the region to be scrubbed or the function doing the scrubbing into dram_timing_info. Thoughts? Cheers, Ahmad > + > endmenu > > endif > diff --git a/drivers/ddr/imx/imx8m_ddr_init.c b/drivers/ddr/imx/imx8m_ddr_init.c > index c16e04d274..6398a2b971 100644 > --- a/drivers/ddr/imx/imx8m_ddr_init.c > +++ b/drivers/ddr/imx/imx8m_ddr_init.c > @@ -45,6 +45,74 @@ static void ddr_cfg_umctl2(struct dram_controller *dram, struct dram_cfg_param * > } > } > > +#ifdef CONFIG_IMX8MP_DRAM_ECC > +void ddrc_inline_ecc_scrub(unsigned int start_address, > + unsigned int range_address) > +{ > + unsigned int tmp; > + > + pr_debug("ECC scrub %08x-%08x\n", start_address, range_address); > + /* Step1: Enable quasi-dynamic programming */ > + reg32_write(DDRC_SWCTL(0), 0x00000000); > + /* Step2: Set ECCCFG1.ecc_parity_region_lock to 1 */ > + reg32setbit(DDRC_ECCCFG1(0), 0x4); > + /* Step3: Block the AXI ports from taking the transaction */ > + reg32_write(DDRC_PCTRL_0(0), 0x0); > + /* Step4: Set scrub start address */ > + reg32_write(DDRC_SBRSTART0(0), start_address); > + /* Step5: Set scrub range address */ > + reg32_write(DDRC_SBRRANGE0(0), range_address); > + /* Step6: Set scrub_mode to write */ > + reg32_write(DDRC_SBRCTL(0), 0x00000014); > + /* Step7: Set the desired pattern through SBRWDATA0 registers */ > + reg32_write(DDRC_SBRWDATA0(0), 0x55aa55aa); > + /* Step8: Enable the SBR by programming SBRCTL.scrub_en=1 */ > + reg32setbit(DDRC_SBRCTL(0), 0x0); > + /* Step9: Poll SBRSTAT.scrub_done=1 */ > + tmp = reg32_read(DDRC_SBRSTAT(0)); > + while (tmp != 0x00000002) > + tmp = reg32_read(DDRC_SBRSTAT(0)) & 0x2; > + /* Step10: Poll SBRSTAT.scrub_busy=0 */ > + tmp = reg32_read(DDRC_SBRSTAT(0)); > + while (tmp != 0x0) > + tmp = reg32_read(DDRC_SBRSTAT(0)) & 0x1; > + /* Step11: Disable SBR by programming SBRCTL.scrub_en=0 */ > + clrbits_le32(DDRC_SBRCTL(0), 0x1); > + /* Step12: Prepare for normal scrub operation(Read) and set scrub_interval*/ > + reg32_write(DDRC_SBRCTL(0), 0xff20); > + /* Step13: Enable the SBR by programming SBRCTL.scrub_en=1 */ > + reg32_write(DDRC_SBRCTL(0), 0xff21); > + /* Step14: Enable AXI ports by programming */ > + reg32_write(DDRC_PCTRL_0(0), 0x1); > + /* Step15: Disable quasi-dynamic programming */ > + reg32_write(DDRC_SWCTL(0), 0x00000001); > +} > + > +void ddrc_inline_ecc_scrub_end(unsigned int start_address, > + unsigned int range_address) > +{ > + pr_debug("ECC end %08x-%08x\n", start_address, range_address); > + /* Step1: Enable quasi-dynamic programming */ > + reg32_write(DDRC_SWCTL(0), 0x00000000); > + /* Step2: Block the AXI ports from taking the transaction */ > + reg32_write(DDRC_PCTRL_0(0), 0x0); > + /* Step3: Set scrub start address */ > + reg32_write(DDRC_SBRSTART0(0), start_address); > + /* Step4: Set scrub range address */ > + reg32_write(DDRC_SBRRANGE0(0), range_address); > + /* Step5: Disable SBR by programming SBRCTL.scrub_en=0 */ > + clrbits_le32(DDRC_SBRCTL(0), 0x1); > + /* Step6: Prepare for normal scrub operation(Read) and set scrub_interval */ > + reg32_write(DDRC_SBRCTL(0), 0x100); > + /* Step7: Enable the SBR by programming SBRCTL.scrub_en=1 */ > + reg32_write(DDRC_SBRCTL(0), 0x101); > + /* Step8: Enable AXI ports by programming */ > + reg32_write(DDRC_PCTRL_0(0), 0x1); > + /* Step9: Disable quasi-dynamic programming */ > + reg32_write(DDRC_SWCTL(0), 0x00000001); > +} > +#endif > + > static unsigned int g_cdd_rr_max[4]; > static unsigned int g_cdd_rw_max[4]; > static unsigned int g_cdd_wr_max[4]; > @@ -642,6 +710,11 @@ int imx8m_ddr_init(struct dram_controller *dram, struct dram_timing_info *dram_t > reg32_write(DDRC_PCTRL_0(0), 0x00000001); > pr_debug("ddrmix config done\n"); > > +#ifdef CONFIG_IMX8MP_DRAM_ECC > + if (dram->ddrc_type == DDRC_TYPE_MP) > + board_dram_ecc_scrub(); > +#endif > + > /* save the dram timing config into memory */ > dram_config_save(dram, dram_timing, IMX8M_SAVED_DRAM_TIMING_BASE); > > diff --git a/include/soc/imx8m/ddr.h b/include/soc/imx8m/ddr.h > index 5df07772b3..08ebf61da0 100644 > --- a/include/soc/imx8m/ddr.h > +++ b/include/soc/imx8m/ddr.h > @@ -186,6 +186,8 @@ > #define DDRC_SBRWDATA0(X) (DDRC_IPS_BASE_ADDR(X) + 0xf2c) > #define DDRC_SBRWDATA1(X) (DDRC_IPS_BASE_ADDR(X) + 0xf30) > #define DDRC_PDCH(X) (DDRC_IPS_BASE_ADDR(X) + 0xf34) > +#define DDRC_SBRSTART0(X) (DDRC_IPS_BASE_ADDR(X) + 0xf38) > +#define DDRC_SBRRANGE0(X) (DDRC_IPS_BASE_ADDR(X) + 0xf40) > > #define DDRC_FREQ1_DERATEEN(X) (DDRC_IPS_BASE_ADDR(X) + 0x2020) > #define DDRC_FREQ1_DERATEINT(X) (DDRC_IPS_BASE_ADDR(X) + 0x2024) > @@ -380,4 +382,13 @@ static inline void imx8m_ddr_load_train_code(enum dram_type dram_type, > ddr_load_train_code(&imx8m_dram_controller, dram_type, fw_type); > } > > +#define DDRC_PHY_REG(x) ((x) * 4) > + > +void board_dram_ecc_scrub(void); > + > +void ddrc_inline_ecc_scrub(unsigned int start_address, > + unsigned int range_address); > +void ddrc_inline_ecc_scrub_end(unsigned int start_address, > + unsigned int range_address); > + > #endif > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |