From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.bootlin.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fQxRb-0003vR-8A for linux-mtd@lists.infradead.org; Thu, 07 Jun 2018 16:07:26 +0000 Date: Thu, 7 Jun 2018 18:07:10 +0200 From: Miquel Raynal To: Naga Sureshkumar Relli Cc: , , , , , , , , , , , , , Subject: Re: [LINUX PATCH v9 2/4] memory: pl353: Add driver for arm pl353 static memory controller Message-ID: <20180607180710.5b53e95b@xps13> In-Reply-To: <1528271382-21690-3-git-send-email-naga.sureshkumar.relli@xilinx.com> References: <1528271382-21690-1-git-send-email-naga.sureshkumar.relli@xilinx.com> <1528271382-21690-3-git-send-email-naga.sureshkumar.relli@xilinx.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Naga, On Wed, 6 Jun 2018 13:19:40 +0530, Naga Sureshkumar Relli wrote: > Add driver for arm pl353 static memory controller. This controller is > used in xilinx zynq soc for interfacing the nand and nor/sram memory > devices. Upper case: Xilinx Zynq, SoC, NAND, NOR, SRAM. >=20 > Signed-off-by: Naga Sureshkumar Relli > --- > Changes in v9: > - Addressed the comments given by Julia Cartwright to the v8 series. > Changes in v8: > - None > Changes in v7: > - Corrected the kconfig to use tristate selection > - Corrected the GPL licence ident=20 > - Added boundary checks for nand timing parameters=20 > Changes in v6: > - Fixed checkpatch.pl reported warnings > Changes in v5: > - Added pl353_smc_get_clkrate function, made pl353_smc_set_cycles as publ= ic > API > - Removed nand timing parameter initialization and moved it to nand drive= r =20 > Changes in v4: > - Modified driver to support multiple instances > - Used sleep instaed of busywait for delay > Changes in v3: > - None > Changes in v2: > - Since now the timing parameters are in nano seconds, added logic to con= vert > them to the cycles > --- > drivers/memory/Kconfig | 8 + > drivers/memory/Makefile | 1 + > drivers/memory/pl353-smc.c | 523 ++++++++++++++++++++++++++= ++++++ > include/linux/platform_data/pl353-smc.h | 29 ++ > 4 files changed, 561 insertions(+) > create mode 100644 drivers/memory/pl353-smc.c > create mode 100644 include/linux/platform_data/pl353-smc.h >=20 > diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig > index 19a0e83..9517da7 100644 > --- a/drivers/memory/Kconfig > +++ b/drivers/memory/Kconfig > @@ -153,6 +153,14 @@ config DA8XX_DDRCTL > Texas Instruments da8xx SoCs. It's used to tweak various memory > controller configuration options. > =20 > +config PL353_SMC > + tristate "ARM PL35X Static Memory Controller(SMC) driver" > + default y This is not restricive at all. If this controller is only on a specific SoC, you should add another condition to compile the driver? > + depends on ARM Or here ^ > + help > + This driver is for the ARM PL351/PL353 Static Memory > + Controller(SMC) module. > + > source "drivers/memory/samsung/Kconfig" > source "drivers/memory/tegra/Kconfig" > =20 > diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile > index 66f5524..58e794d 100644 > --- a/drivers/memory/Makefile > +++ b/drivers/memory/Makefile > @@ -20,6 +20,7 @@ obj-$(CONFIG_TEGRA20_MC) +=3D tegra20-mc.o > obj-$(CONFIG_JZ4780_NEMC) +=3D jz4780-nemc.o > obj-$(CONFIG_MTK_SMI) +=3D mtk-smi.o > obj-$(CONFIG_DA8XX_DDRCTL) +=3D da8xx-ddrctl.o > +obj-$(CONFIG_PL353_SMC) +=3D pl353-smc.o > =20 > obj-$(CONFIG_SAMSUNG_MC) +=3D samsung/ > obj-$(CONFIG_TEGRA_MC) +=3D tegra/ > diff --git a/drivers/memory/pl353-smc.c b/drivers/memory/pl353-smc.c > new file mode 100644 > index 0000000..8758930 > --- /dev/null > +++ b/drivers/memory/pl353-smc.c > @@ -0,0 +1,523 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * ARM PL353 SMC driver > + * > + * Copyright (C) 2012 Xilinx, Inc > + * Author: Punnaiah Choudary Kalluri > + * Author: Naga Sureshkumar Relli > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Register definitions */ > +#define PL353_SMC_MEMC_STATUS_OFFS 0 /* Controller status reg, RO */ > +#define PL353_SMC_CFG_CLR_OFFS 0xC /* Clear config reg, WO */ > +#define PL353_SMC_DIRECT_CMD_OFFS 0x10 /* Direct command reg, WO */ > +#define PL353_SMC_SET_CYCLES_OFFS 0x14 /* Set cycles register, WO */ > +#define PL353_SMC_SET_OPMODE_OFFS 0x18 /* Set opmode register, WO */ > +#define PL353_SMC_ECC_STATUS_OFFS 0x400 /* ECC status register */ > +#define PL353_SMC_ECC_MEMCFG_OFFS 0x404 /* ECC mem config reg */ > +#define PL353_SMC_ECC_MEMCMD1_OFFS 0x408 /* ECC mem cmd1 reg */ > +#define PL353_SMC_ECC_MEMCMD2_OFFS 0x40C /* ECC mem cmd2 reg */ > +#define PL353_SMC_ECC_VALUE0_OFFS 0x418 /* ECC value 0 reg */ > + > +/* Controller status register specific constants */ > +#define PL353_SMC_MEMC_STATUS_RAW_INT_1_SHIFT 6 > + > +/* Clear configuration register specific constants */ > +#define PL353_SMC_CFG_CLR_INT_CLR_1 0x10 > +#define PL353_SMC_CFG_CLR_ECC_INT_DIS_1 0x40 > +#define PL353_SMC_CFG_CLR_INT_DIS_1 0x2 > +#define PL353_SMC_CFG_CLR_DEFAULT_MASK (PL353_SMC_CFG_CLR_INT_CLR_1 | \ > + PL353_SMC_CFG_CLR_ECC_INT_DIS_1 | \ > + PL353_SMC_CFG_CLR_INT_DIS_1) > + > +/* Set cycles register specific constants */ > +#define PL353_SMC_SET_CYCLES_T0_MASK 0xF > +#define PL353_SMC_SET_CYCLES_T0_SHIFT 0 > +#define PL353_SMC_SET_CYCLES_T1_MASK 0xF > +#define PL353_SMC_SET_CYCLES_T1_SHIFT 4 > +#define PL353_SMC_SET_CYCLES_T2_MASK 0x7 > +#define PL353_SMC_SET_CYCLES_T2_SHIFT 8 > +#define PL353_SMC_SET_CYCLES_T3_MASK 0x7 > +#define PL353_SMC_SET_CYCLES_T3_SHIFT 11 > +#define PL353_SMC_SET_CYCLES_T4_MASK 0x7 > +#define PL353_SMC_SET_CYCLES_T4_SHIFT 14 > +#define PL353_SMC_SET_CYCLES_T5_MASK 0x7 > +#define PL353_SMC_SET_CYCLES_T5_SHIFT 17 > +#define PL353_SMC_SET_CYCLES_T6_MASK 0xF > +#define PL353_SMC_SET_CYCLES_T6_SHIFT 20 > + > +/* ECC status register specific constants */ > +#define PL353_SMC_ECC_STATUS_BUSY BIT(6) > + > +/* ECC memory config register specific constants */ > +#define PL353_SMC_ECC_MEMCFG_MODE_MASK 0xC > +#define PL353_SMC_ECC_MEMCFG_MODE_SHIFT 2 > +#define PL353_SMC_ECC_MEMCFG_PGSIZE_MASK 0xC > + > +#define PL353_SMC_DC_UPT_NAND_REGS ((4 << 23) | /* CS: NAND chip */ \ > + (2 << 21)) /* UpdateRegs operation */ > + > +#define PL353_NAND_ECC_CMD1 ((0x80) | /* Write command */ \ > + (0 << 8) | /* Read command */ \ > + (0x30 << 16) | /* Read End command */ \ > + (1 << 24)) /* Read End command calid */ > + > +#define PL353_NAND_ECC_CMD2 ((0x85) | /* Write col change cmd */ \ > + (5 << 8) | /* Read col change cmd */ \ > + (0xE0 << 16) | /* Read col change end cmd */ \ > + (1 << 24)) /* Read col change end cmd valid */ > +#define PL353_NAND_ECC_BUSY_TIMEOUT (1 * HZ) > +/** > + * struct pl353_smc_data - Private smc driver structure > + * @devclk: Pointer to the peripheral clock > + * @aperclk: Pointer to the APER clock > + */ > +struct pl353_smc_data { > + struct clk *memclk; > + struct clk *aclk; > +}; > + > +/* SMC virtual register base */ > +static void __iomem *pl353_smc_base; > + > +/** > + * pl353_smc_set_buswidth - Set memory buswidth > + * @bw: Memory buswidth (8 | 16) > + * Return: 0 on success or negative errno. > + */ > +int pl353_smc_set_buswidth(unsigned int bw) > +{ > + if (bw !=3D PL353_SMC_MEM_WIDTH_8 && bw !=3D PL353_SMC_MEM_WIDTH_16) > + return -EINVAL; > + > + writel(bw, pl353_smc_base + PL353_SMC_SET_OPMODE_OFFS); > + writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc_base + > + PL353_SMC_DIRECT_CMD_OFFS); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(pl353_smc_set_buswidth); > + > +/** > + * pl353_smc_set_cycles - Set memory timing parameters > + * @t0: t_rc read cycle time > + * @t1: t_wc write cycle time > + * @t2: t_rea/t_ceoe output enable assertion delay > + * @t3: t_wp write enable deassertion delay > + * @t4: t_clr/t_pc page cycle time > + * @t5: t_ar/t_ta ID read time/turnaround time > + * @t6: t_rr busy to RE timing > + * > + * Sets NAND chip specific timing parameters. > + */ > +static void pl353_smc_set_cycles(u32 t0, u32 t1, u32 t2, u32 t3, u32 > + t4, u32 t5, u32 t6) > +{ > + t0 &=3D PL353_SMC_SET_CYCLES_T0_MASK; > + t1 =3D (t1 & PL353_SMC_SET_CYCLES_T1_MASK) << > + PL353_SMC_SET_CYCLES_T1_SHIFT; > + t2 =3D (t2 & PL353_SMC_SET_CYCLES_T2_MASK) << > + PL353_SMC_SET_CYCLES_T2_SHIFT; > + t3 =3D (t3 & PL353_SMC_SET_CYCLES_T3_MASK) << > + PL353_SMC_SET_CYCLES_T3_SHIFT; > + t4 =3D (t4 & PL353_SMC_SET_CYCLES_T4_MASK) << > + PL353_SMC_SET_CYCLES_T4_SHIFT; > + t5 =3D (t5 & PL353_SMC_SET_CYCLES_T5_MASK) << > + PL353_SMC_SET_CYCLES_T5_SHIFT; > + t6 =3D (t6 & PL353_SMC_SET_CYCLES_T6_MASK) << > + PL353_SMC_SET_CYCLES_T6_SHIFT; > + > + t0 |=3D t1 | t2 | t3 | t4 | t5 | t6; > + > + writel(t0, pl353_smc_base + PL353_SMC_SET_CYCLES_OFFS); > + writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc_base + > + PL353_SMC_DIRECT_CMD_OFFS); > +} > + > +/** > + * pl353_smc_ecc_is_busy - Read ecc busy flag > + * Return: the ecc_status bit from the ecc_status register. 1 =3D busy, = 0 =3D idle > + */ > +int pl353_smc_ecc_is_busy(void) > +{ > + return !!(readl(pl353_smc_base + PL353_SMC_ECC_STATUS_OFFS) & > + PL353_SMC_ECC_STATUS_BUSY); You can return a bool and avoid the '!!'. > +} > +EXPORT_SYMBOL_GPL(pl353_smc_ecc_is_busy); > + > +/** > + * pl353_smc_get_ecc_val - Read ecc_valueN registers > + * @ecc_reg: Index of the ecc_value reg (0..3) > + * Return: the content of the requested ecc_value register. > + * > + * There are four valid ecc_value registers. The argument is truncated t= o stay > + * within this valid boundary. > + */ > +u32 pl353_smc_get_ecc_val(int ecc_reg) > +{ > + u32 addr, reg; > + > + ecc_reg &=3D 3; This is not readable. Please check for the validity of ecc_reg with standard '<' '>' operators. > + addr =3D PL353_SMC_ECC_VALUE0_OFFS + (ecc_reg << 2); 2 should be defined > + reg =3D readl(pl353_smc_base + addr); > + > + return reg; > +} > +EXPORT_SYMBOL_GPL(pl353_smc_get_ecc_val); > + > +/** > + * pl353_smc_get_nand_int_status_raw - Get NAND interrupt status bit > + * Return: the raw_int_status1 bit from the memc_status register If you use kernel-doc format, should be "@return". > + */ > +int pl353_smc_get_nand_int_status_raw(void) > +{ > + u32 reg; > + > + reg =3D readl(pl353_smc_base + PL353_SMC_MEMC_STATUS_OFFS); > + reg >>=3D PL353_SMC_MEMC_STATUS_RAW_INT_1_SHIFT; > + reg &=3D 1; > + > + return reg; > +} > +EXPORT_SYMBOL_GPL(pl353_smc_get_nand_int_status_raw); > + > +/** > + * pl353_smc_clr_nand_int - Clear NAND interrupt > + */ > +void pl353_smc_clr_nand_int(void) > +{ > + writel(PL353_SMC_CFG_CLR_INT_CLR_1, > + pl353_smc_base + PL353_SMC_CFG_CLR_OFFS); > +} > +EXPORT_SYMBOL_GPL(pl353_smc_clr_nand_int); > + > +/** > + * pl353_smc_set_ecc_mode - Set SMC ECC mode > + * @mode: ECC mode (BYPASS, APB, MEM) > + * Return: 0 on success or negative errno. > + */ > +int pl353_smc_set_ecc_mode(enum pl353_smc_ecc_mode mode) > +{ > + u32 reg; > + int ret =3D 0; > + > + switch (mode) { > + case PL353_SMC_ECCMODE_BYPASS: > + case PL353_SMC_ECCMODE_APB: > + case PL353_SMC_ECCMODE_MEM: > + > + reg =3D readl(pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS); > + reg &=3D ~PL353_SMC_ECC_MEMCFG_MODE_MASK; > + reg |=3D mode << PL353_SMC_ECC_MEMCFG_MODE_SHIFT; > + writel(reg, pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS); > + > + break; > + default: > + ret =3D -EINVAL; > + } > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(pl353_smc_set_ecc_mode); > + > +/** > + * pl353_smc_set_ecc_pg_size - Set SMC ECC page size > + * @pg_sz: ECC page size > + * Return: 0 on success or negative errno. > + */ > +int pl353_smc_set_ecc_pg_size(unsigned int pg_sz) > +{ > + u32 reg, sz; > + > + switch (pg_sz) { > + case 0: > + sz =3D 0; > + break; > + case SZ_512: > + sz =3D 1; > + break; > + case SZ_1K: > + sz =3D 2; > + break; > + case SZ_2K: > + sz =3D 3; > + break; > + default: > + return -EINVAL; > + } > + > + reg =3D readl(pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS); > + reg &=3D ~PL353_SMC_ECC_MEMCFG_PGSIZE_MASK; > + reg |=3D sz; > + writel(reg, pl353_smc_base + PL353_SMC_ECC_MEMCFG_OFFS); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(pl353_smc_set_ecc_pg_size); > + > +static int __maybe_unused pl353_smc_suspend(struct device *dev) > +{ > + struct pl353_smc_data *pl353_smc =3D dev_get_drvdata(dev); > + > + clk_disable(pl353_smc->memclk); > + clk_disable(pl353_smc->aclk); Are you sure you don't need to save any of the configured registers? > + > + return 0; > +} > + > +static int __maybe_unused pl353_smc_resume(struct device *dev) > +{ > + int ret; > + struct pl353_smc_data *pl353_smc =3D dev_get_drvdata(dev); > + > + ret =3D clk_enable(pl353_smc->aclk); > + if (ret) { > + dev_err(dev, "Cannot enable axi domain clock.\n"); > + return ret; > + } > + > + ret =3D clk_enable(pl353_smc->memclk); > + if (ret) { > + dev_err(dev, "Cannot enable memory clock.\n"); > + clk_disable(pl353_smc->aclk); > + return ret; > + } New line > + return ret; > +} > + > +static SIMPLE_DEV_PM_OPS(pl353_smc_dev_pm_ops, pl353_smc_suspend, > + pl353_smc_resume); > + > +/** > + * pl353_smc_init_nand_interface - Initialize the NAND interface > + * @pdev: Pointer to the platform_device struct > + * @nand_node: Pointer to the pl353_nand device_node struct > + */ > +static void pl353_smc_init_nand_interface(struct platform_device *pdev, > + struct device_node *nand_node) > +{ > + u32 t_rc, t_wc, t_rea, t_wp, t_clr, t_ar, t_rr; > + int err; > + unsigned long timeout =3D jiffies + PL353_NAND_ECC_BUSY_TIMEOUT; Maybe this should be defined later in the code. New line. > + /* nand-cycle- property is refer to the NAND flash timing > + * mapping between dts and the NAND flash AC timing > + * X : AC timing name > + * t0 : t_rc > + * t1 : t_wc > + * t2 : t_rea > + * t3 : t_wp > + * t4 : t_clr > + * t5 : t_ar > + * t6 : t_rr > + */ > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t0", &t_rc); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t0 not in device tree"); > + goto default_nand_timing; > + } > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t1", &t_wc); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t1 not in device tree"); > + goto default_nand_timing; > + } > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t2", &t_rea); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t2 not in device tree"); > + goto default_nand_timing; > + } > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t3", &t_wp); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t3 not in device tree"); > + goto default_nand_timing; > + } > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t4", &t_clr); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t4 not in device tree"); > + goto default_nand_timing; > + } > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t5", &t_ar); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t5 not in device tree"); > + goto default_nand_timing; > + } > + err =3D of_property_read_u32(nand_node, "arm,nand-cycle-t6", &t_rr); > + if (err) { > + dev_warn(&pdev->dev, "arm,nand-cycle-t6 not in device tree"); > + goto default_nand_timing; > + } See the comment in the bindings about this section. > + > +default_nand_timing: > + /* > + * Default assume 50MHz clock (20ns cycle time) and 3V operation > + * The SET_CYCLES_REG register value depends on the flash device. > + * Look in to the device datasheet and change its value, This value > + * is for 2Gb Numonyx flash. No :) The controller is not supposed to work with only one chip, right? So it should not embed any chip-specific information. If this chip is not ONFI nor JEDEC and is not supported yet, the right way to do is to write a manufacturer driver. > + */ > + if (err) { > + /* set default NAND flash timing property */ > + dev_warn(&pdev->dev, "Using default timing for"); > + dev_warn(&pdev->dev, "2Gb Numonyx MT29F2G08ABAEAWP NAND flash"); > + dev_warn(&pdev->dev, "t_wp, t_clr, t_ar are set to 2"); > + dev_warn(&pdev->dev, "t_rc, t_wc, t_rr are set to 4"); > + dev_warn(&pdev->dev, "t_rea is set to 1"); > + t_rc =3D 4; > + t_wc =3D 4; > + t_rr =3D 4; > + t_rea =3D 1; > + t_wp =3D 2; > + t_clr =3D 2; > + t_ar =3D 2; > + } > + > + pl353_smc_set_buswidth(PL353_SMC_MEM_WIDTH_8); > + pl353_smc_set_cycles(t_rc, t_wc, t_rea, t_wp, t_clr, t_ar, t_rr); > + writel(PL353_SMC_CFG_CLR_INT_CLR_1, > + pl353_smc_base + PL353_SMC_CFG_CLR_OFFS); > + writel(PL353_SMC_DC_UPT_NAND_REGS, pl353_smc_base + > + PL353_SMC_DIRECT_CMD_OFFS); > + /* Wait till the ECC operation is complete */ > + do { > + if (pl353_smc_ecc_is_busy()) > + cpu_relax(); > + else > + break; > + } while (!time_after_eq(jiffies, timeout)); > + > + if (time_after_eq(jiffies, timeout)) > + dev_err(&pdev->dev, "nand ecc busy status timed out"); > + > + writel(PL353_NAND_ECC_CMD1, > + pl353_smc_base + PL353_SMC_ECC_MEMCMD1_OFFS); > + writel(PL353_NAND_ECC_CMD2, > + pl353_smc_base + PL353_SMC_ECC_MEMCMD2_OFFS); > +} > + > +static const struct of_device_id pl353_smc_supported_children[] =3D { > + { .compatible =3D "cfi-flash" }, > + { .compatible =3D "arm,pl353-nand-r2p1", > + .data =3D pl353_smc_init_nand_interface }, Please put the compatibles on another line and align data with them. > + {} > +}; > + > +static int pl353_smc_probe(struct platform_device *pdev) > +{ > + struct pl353_smc_data *pl353_smc; > + struct device_node *child; > + struct resource *res; > + int err; > + struct device_node *of_node =3D pdev->dev.of_node; > + void (*init)(struct platform_device *pdev, > + struct device_node *nand_node); > + const struct of_device_id *match =3D NULL; > + > + pl353_smc =3D devm_kzalloc(&pdev->dev, sizeof(*pl353_smc), GFP_KERNEL); > + if (!pl353_smc) > + return -ENOMEM; > + > + /* Get the NAND controller virtual address */ > + res =3D platform_get_resource(pdev, IORESOURCE_MEM, 0); > + pl353_smc_base =3D devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(pl353_smc_base)) > + return PTR_ERR(pl353_smc_base); > + > + pl353_smc->aclk =3D devm_clk_get(&pdev->dev, "aclk"); > + if (IS_ERR(pl353_smc->aclk)) { > + dev_err(&pdev->dev, "aclk clock not found.\n"); > + return PTR_ERR(pl353_smc->aclk); > + } > + > + pl353_smc->memclk =3D devm_clk_get(&pdev->dev, "memclk"); > + if (IS_ERR(pl353_smc->memclk)) { > + dev_err(&pdev->dev, "memclk clock not found.\n"); > + return PTR_ERR(pl353_smc->memclk); > + } > + > + err =3D clk_prepare_enable(pl353_smc->aclk); > + if (err) { > + dev_err(&pdev->dev, "Unable to enable AXI clock.\n"); > + return err; > + } > + > + err =3D clk_prepare_enable(pl353_smc->memclk); > + if (err) { > + dev_err(&pdev->dev, "Unable to enable memory clock.\n"); > + goto out_clk_dis_aper; > + } > + > + platform_set_drvdata(pdev, pl353_smc); > + > + /* clear interrupts */ > + writel(PL353_SMC_CFG_CLR_DEFAULT_MASK, > + pl353_smc_base + PL353_SMC_CFG_CLR_OFFS); > + > + /* Find compatible children. Only a single child is supported */ > + for_each_available_child_of_node(of_node, child) { > + match =3D of_match_node(pl353_smc_supported_children, child); > + if (!match) { > + dev_warn(&pdev->dev, "unsupported child node\n"); > + continue; > + } > + break; > + } > + if (!match) { > + dev_err(&pdev->dev, "no matching children\n"); > + goto out_clk_disable; > + } > + > + init =3D match->data; > + if (init) > + init(pdev, child); > + of_platform_device_create(child, NULL, &pdev->dev); > + > + return 0; > + > +out_clk_disable: > + clk_disable_unprepare(pl353_smc->memclk); > +out_clk_dis_aper: > + clk_disable_unprepare(pl353_smc->aclk); > + > + return err; > +} > + > +static int pl353_smc_remove(struct platform_device *pdev) > +{ > + struct pl353_smc_data *pl353_smc =3D platform_get_drvdata(pdev); > + > + clk_disable_unprepare(pl353_smc->memclk); > + clk_disable_unprepare(pl353_smc->aclk); > + > + return 0; > +} > + > +/* Match table for device tree binding */ > +static const struct of_device_id pl353_smc_of_match[] =3D { > + { .compatible =3D "arm,pl353-smc-r2p1" }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, pl353_smc_of_match); > + > +static struct platform_driver pl353_smc_driver =3D { > + .probe =3D pl353_smc_probe, > + .remove =3D pl353_smc_remove, > + .driver =3D { > + .name =3D "pl353-smc", > + .pm =3D &pl353_smc_dev_pm_ops, > + .of_match_table =3D pl353_smc_of_match, > + }, > +}; > + > +module_platform_driver(pl353_smc_driver); > + > +MODULE_AUTHOR("Xilinx, Inc."); > +MODULE_DESCRIPTION("ARM PL353 SMC Driver"); > +MODULE_LICENSE("GPL"); > diff --git a/include/linux/platform_data/pl353-smc.h b/include/linux/plat= form_data/pl353-smc.h I don't think you really need a separate file for these enums? Unless it is really platform specific? > new file mode 100644 > index 0000000..fc4129e > --- /dev/null > +++ b/include/linux/platform_data/pl353-smc.h > @@ -0,0 +1,29 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * ARM PL353 SMC Driver Header > + * > + * Copyright (C) 2017 Xilinx, Inc > + */ > + > +#ifndef __LINUX_MEMORY_PL353_SMC_H > +#define __LINUX_MEMORY_PL353_SMC_H > + > +enum pl353_smc_ecc_mode { > + PL353_SMC_ECCMODE_BYPASS =3D 0, > + PL353_SMC_ECCMODE_APB =3D 1, > + PL353_SMC_ECCMODE_MEM =3D 2 > +}; > + > +enum pl353_smc_mem_width { > + PL353_SMC_MEM_WIDTH_8 =3D 0, > + PL353_SMC_MEM_WIDTH_16 =3D 1 > +}; > + > +u32 pl353_smc_get_ecc_val(int ecc_reg); > +int pl353_smc_ecc_is_busy(void); > +int pl353_smc_get_nand_int_status_raw(void); > +void pl353_smc_clr_nand_int(void); > +int pl353_smc_set_ecc_mode(enum pl353_smc_ecc_mode mode); > +int pl353_smc_set_ecc_pg_size(unsigned int pg_sz); > +int pl353_smc_set_buswidth(unsigned int bw); > +#endif Thanks, Miqu=C3=A8l --=20 Miquel Raynal, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com