From: Scott Wood Date: Thu, 19 Jun 2014 20:39:20 -0500 Subject: [U-Boot] [U-Boot, v8] nand/denali: Adding Denali NAND driver support In-Reply-To: <1402378939-2320-1-git-send-email-clsee@altera.com> References: <1402378939-2320-1-git-send-email-clsee@altera.com> Message-ID: <20140620013920.GA6586@home.buserror.net> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Tue, Jun 10, 2014 at 12:42:19AM -0500, Chin Liang See wrote: > To add the Denali NAND driver support into U-Boot. It required > information such as register base address from configuration > header file within include/configs folder. This is hard to parse. What exactly is required from include/configs and where is it documented? I see that this driver exists in Linux... Is this patch related to a particular Linux SHA1? > Signed-off-by: Chin Liang See > Cc: Artem Bityutskiy > Cc: David Woodhouse > Cc: Brian Norris > Cc: Scott Wood > Cc: Masahiro Yamada > Signed-off-by: Masahiro Yamada > Reviewed-by: Masahiro Yamada > Tested-by: Masahiro Yamada Are these people on CC because they're involved in the U-Boot patch in some way, or is this just copy-and-paste from a Linux patch? > +/* Reset the flash controller */ > +static uint32_t denali_nand_reset(struct denali_nand_info *denali) > +{ > + uint32_t i; > + > + for (i = 0; i < denali->max_banks; i++) > + writel(INTR_STATUS__RST_COMP | INTR_STATUS__TIME_OUT, > + denali->flash_reg + INTR_STATUS(i)); > + > + for (i = 0; i < denali->max_banks; i++) { > + writel(1 << i, denali->flash_reg + DEVICE_RESET); > + while (!(readl(denali->flash_reg + INTR_STATUS(i)) & > + (INTR_STATUS__RST_COMP | INTR_STATUS__TIME_OUT))) > + if (readl(denali->flash_reg + INTR_STATUS(i)) & > + INTR_STATUS__TIME_OUT) > + debug(KERN_DEBUG "NAND Reset operation " > + "timed out on bank %d\n", i); > + } WARNING: quoted string split across lines #283: FILE: drivers/mtd/nand/denali.c:203: + debug(KERN_DEBUG "NAND Reset operation " + "timed out on bank %d\n", i); (likewise elsewhere) This instance is not even from Linux -- and where does KERN_DEBUG come from? The Linux driver has never used it. > +#if ONFI_BLOOM_TIME > + if ((en_hi * CLK_X) < (treh[mode] + 2)) > + en_hi++; > +#endif When would this #if not be true? > + if ((en_lo + en_hi) * CLK_X < trc[mode]) > + en_lo += DIV_ROUND_UP((trc[mode] - (en_lo + en_hi) * CLK_X), > + CLK_X); > + > + if ((en_lo + en_hi) < CLK_MULTI) > + en_lo += CLK_MULTI - en_lo - en_hi; > + > + while (dv_window < 8) { > + data_invalid_rhoh = en_lo * CLK_X + trhoh[mode]; > + > + data_invalid_rloh = (en_lo + en_hi) * CLK_X + trloh[mode]; > + > + data_invalid = > + data_invalid_rhoh < > + data_invalid_rloh ? data_invalid_rhoh : data_invalid_rloh; > + > + dv_window = data_invalid - trea[mode]; > + > + if (dv_window < 8) > + en_lo++; > + } > + > + acc_clks = DIV_ROUND_UP(trea[mode], CLK_X); > + > + while (((acc_clks * CLK_X) - trea[mode]) < 3) > + acc_clks++; > + > + if ((data_invalid - acc_clks * CLK_X) < 2) > + debug(KERN_WARNING "%s, Line %d: Warning!\n", > + __FILE__, __LINE__); > + > + addr_2_data = DIV_ROUND_UP(tadl[mode], CLK_X); > + re_2_we = DIV_ROUND_UP(trhw[mode], CLK_X); > + re_2_re = DIV_ROUND_UP(trhz[mode], CLK_X); > + we_2_re = DIV_ROUND_UP(twhr[mode], CLK_X); > + cs_cnt = DIV_ROUND_UP((tcs[mode] - trp[mode]), CLK_X); > + if (!tclsrising) > + cs_cnt = DIV_ROUND_UP(tcs[mode], CLK_X); > + if (cs_cnt == 0) > + cs_cnt = 1; > + > + if (tcea[mode]) { > + while (((cs_cnt * CLK_X) + trea[mode]) < tcea[mode]) > + cs_cnt++; > + } > + > +#if MODE5_WORKAROUND > + if (mode == 5) > + acc_clks = 5; > +#endif Likewise, this is dead code. If these are meant to be configurable, they need to be named as config symbols, documented, and located in a config file rather than denali.h -- and ideally there should be at least one board that sets the option and at least one that does not set it, so that both possibilities get build coverage. I see that the Linux driver has the same thing, so perhaps we can excuse it if it's not actually meant to be altered by a user, but in that case the driver ought to actually correspond to a specific SHA1 of the Linux driver. > +/* validation function to verify that the controlling software is making > + * a valid request > + */ > +static inline bool is_flash_bank_valid(int flash_bank) > +{ > + return (flash_bank >= 0 && flash_bank < 4); > +} ERROR: return is not a function, parentheses are not required #589: FILE: drivers/mtd/nand/denali.c:509: + return (flash_bank >= 0 && flash_bank < 4); > +/* setups the HW to perform the data DMA */ > +static void denali_setup_dma(struct denali_nand_info *denali, int op) > +{ > + uint32_t mode; > + const int page_count = 1; > + uint32_t addr = (uint32_t)denali->buf.dma_buf; > + > + flush_dcache_range(addr, addr + sizeof(denali->buf.dma_buf)); > + > +#ifdef CONFIG_NAND_DENALI_64BIT Needs to be documented -- and depending on what it means, should possibly be CONFIG_SYS_NAND_DENALI_64BIT. The Linux driver seems to only have the "else" variant. > +static int write_page(struct mtd_info *mtd, struct nand_chip *chip, > + const uint8_t *buf, bool raw_xfer, int oob_required) > +{ > + struct denali_nand_info *denali = mtd_to_denali(mtd); > + > + uint32_t irq_status = 0; > + uint32_t irq_mask = INTR_STATUS__DMA_CMD_COMP; > + > + denali->status = 0; > + > + /* copy buffer into DMA buffer */ > + memcpy((void *)denali->buf.dma_buf, buf, mtd->writesize); Why do you have this cast? > + /* need extra memcpoy for raw transfer */ memcpoy? > + /* check whether any ECC error */ > + if (irq_status & INTR_STATUS__ECC_UNCOR_ERR) { > + /* is the ECC cause by erase page, check using read_page_raw */ > + debug(" Uncorrected ECC detected\n"); > + denali_read_page_raw(mtd, chip, buf, oob_required, denali->page); WARNING: line over 80 characters #1044: FILE: drivers/mtd/nand/denali.c:964: + denali_read_page_raw(mtd, chip, buf, oob_required, denali->page); -Scott