From patchwork Sat Jan 23 07:53:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lauri Kasanen X-Patchwork-Id: 12041179 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C862BC433E0 for ; Sat, 23 Jan 2021 07:54:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8DB8F23A74 for ; Sat, 23 Jan 2021 07:54:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726718AbhAWHxs (ORCPT ); Sat, 23 Jan 2021 02:53:48 -0500 Received: from mout.gmx.net ([212.227.15.15]:37721 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726558AbhAWHxr (ORCPT ); Sat, 23 Jan 2021 02:53:47 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1611388305; bh=I7y8lgtQprGrYsFRSWeEo7QY//ZQ3LUijxm4+cjWkeY=; h=X-UI-Sender-Class:Date:From:To:Cc:Subject; b=XQotjEe3vc0r5r674rsNuV3fyIAmse4yzhcNFRBCdo1TTbu8NDBUvQaP8fKb39gUy MbaBen1lTUvMEb+NsLgBLBYR7b3iiXaSBedDV7EX3pZyfuq5bTQJUuCSEIcKVLEmmS i6CM9q9ANNIvYOhyhX/YqjQ/SNGXEXM+NHZGdC8s= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from Valinor ([82.203.161.65]) by mail.gmx.net (mrgmx005 [212.227.17.184]) with ESMTPSA (Nemesis) id 1N2mFi-1m1Y4b2fM4-0134Om; Sat, 23 Jan 2021 08:51:45 +0100 Date: Sat, 23 Jan 2021 09:53:27 +0200 From: Lauri Kasanen To: linux-mips@vger.kernel.org Cc: tsbogend@alpha.franken.de, axboe@kernel.dk, linux-block@vger.kernel.org, Keith Busch , Christoph Hellwig Subject: [PATCH v11] block: Add n64 cart driver Message-Id: <20210123095327.58e5ab6c05f38e9080a79bd3@gmx.com> X-Mailer: Sylpheed 3.5.0 (GTK+ 2.18.6; x86_64-unknown-linux-gnu) Mime-Version: 1.0 X-Provags-ID: V03:K1:QLR8caUaHO+Gglm0BoG3y+jpcJMs847lZOJQJQklBmPO/DBdzlI pbNX3wXZPbR5uryCGxo3cmMeTgdwB2rScX3PUGhW+OIoUFvahl3RATERR2UCLiU2VYWc5FM Q3LErVsckCYsOwyop5KRwWKwk6ZTzCKTE1rOK3P8aG22JYQqtqADcCT3Y1siJ9eZ3/jTg/k Ynv0q1TbsyC3BfZGJEi3w== X-UI-Out-Filterresults: notjunk:1;V03:K0:OpvZIb/0nfw=:7R8P1unyf2KkiGnj3pKocu oX6EGF6tz9sNs9onskI8KOcb1pmAATRu2tDmXUQgF1rd/oDx59dFe85dT8KBuAqIyjpEeBKYn g3lSibKXscinfPeqmjpSCJvHMNGYB1Fpwg/7g6qs6FopIGltqpa7bB/Ter4LmPxqtXVhtohlR i3hWHQEb6MtBPDW/Q6NATIWMsixev5iVhvc+7Wk/28JY0dh46oDoTPX6R+4+mAK0VDP7gh0o8 AO9GelGRhvqtVDNz/ItC9rfiMPdQz6hc80uEZmVyoRwKB7ixL+HDfJGKmr+CN0oW4SZTHUvC8 6d6oQLepiYlRIplrXarpfBlV9PQB/PKKLkESL/IXimNbLBXO+KvsXWBbNFTq2BFO2vpIJkyYs TUgQajtZmNLqF661oFDaQk9YCUf26CBa5f6ZW9kjkQmoB4KS1fX7+a3HMxDDe1tLVVf7KlZz0 mtzpK0XyGJFxxq6zfL6FHoKsNUi4S9Un53MQSxr4dDxnmWRY9m8QzcEu7bABy/i+RGYHksKEg pP9LRYP9Bub1ZXbzTQFGkI2v0ecaHaB5AFmpRL2uy46WrXnXNLMrDs1GgmRXAsYhTyI0W1StV thxq/3ySsd15zQbVGjGSLeRHsjVq47q/i+mSHGNEw2F+NkBtzUoNr6Xdq07nI4mGspo/dQJu1 9v1lazoWjtlxJNuoUpFbQm4REflpMr4qOIoS8dr0MYVUA2s6jwOj9QDzFS6UzAdDoEVXJkDCj ucz7JUql+C2nmW1kR0YNNtGwec4unji5bDAbJA6TwdiLEGfDSTa4GIYlMENwDhgoTzTRAoBUV L77mAOSdhmOMhtpi3Zz6+sYfrtj8K6sbjAx5DUNwnFly3hmYPw2pWSA0wnVwhvKUfbqlItXSy BQms0rPvX5kSnOaeBDDA== Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This adds support for the Nintendo 64 console's carts. Carts are a read-only media ranging from 8mb to 64mb. Only one cart can be connected at once, and switching it requires a reboot. No module support to save RAM, as the target has 8mb RAM. Signed-off-by: Lauri Kasanen Reviewed-by: Christoph Hellwig Reviewed-by: Chaitanya Kulkarni --- drivers/block/Kconfig | 6 ++ drivers/block/Makefile | 1 + drivers/block/n64cart.c | 189 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 196 insertions(+) create mode 100644 drivers/block/n64cart.c v11: bool n64cart_do_bvec remove bio_end_sector() > get_capacity() check pass bvec to helper, remove some local vars v10: convert to bio DMA directly to the bio buffer v9: cosmetics min_t v8: SZ_64K remove barriers add defines for block domain constants __blk_mq_end_request remove register_blkdev via GENHD_FL_EXT_DEVT dma_alloc_noncoherent, sync -- 2.6.2 diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index ecceaaa..924d768 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -72,6 +72,12 @@ config AMIGA_Z2RAM To compile this driver as a module, choose M here: the module will be called z2ram. +config N64CART + bool "N64 cart support" + depends on MACH_NINTENDO64 + help + Support for the N64 cart. + config CDROM tristate select BLK_SCSI_REQUEST diff --git a/drivers/block/Makefile b/drivers/block/Makefile index e1f6311..b9642cf 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -17,6 +17,7 @@ obj-$(CONFIG_PS3_DISK) += ps3disk.o obj-$(CONFIG_PS3_VRAM) += ps3vram.o obj-$(CONFIG_ATARI_FLOPPY) += ataflop.o obj-$(CONFIG_AMIGA_Z2RAM) += z2ram.o +obj-$(CONFIG_N64CART) += n64cart.o obj-$(CONFIG_BLK_DEV_RAM) += brd.o obj-$(CONFIG_BLK_DEV_LOOP) += loop.o obj-$(CONFIG_XILINX_SYSACE) += xsysace.o diff --git a/drivers/block/n64cart.c b/drivers/block/n64cart.c new file mode 100644 index 0000000..e76722a --- /dev/null +++ b/drivers/block/n64cart.c @@ -0,0 +1,189 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for the N64 cart. + * + * Copyright (c) 2021 Lauri Kasanen + */ + +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Lauri Kasanen "); +MODULE_DESCRIPTION("Driver for the N64 cart"); +MODULE_LICENSE("GPL"); + +static unsigned int start, size; +static u32 __iomem *reg_base; +static struct device *dev; + +#define PI_DRAM_REG 0 +#define PI_CART_REG 1 +#define PI_READ_REG 2 +#define PI_WRITE_REG 3 +#define PI_STATUS_REG 4 + +#define PI_STATUS_DMA_BUSY (1 << 0) +#define PI_STATUS_IO_BUSY (1 << 1) + +#define CART_DOMAIN 0x10000000 +#define CART_MAX 0x1FFFFFFF + +#define MIN_ALIGNMENT 8 + +static void n64cart_write_reg(const u8 reg, const u32 value) +{ + writel(value, reg_base + reg); +} + +static u32 n64cart_read_reg(const u8 reg) +{ + return readl(reg_base + reg); +} + +static void n64cart_wait_dma(void) +{ + while (n64cart_read_reg(PI_STATUS_REG) & + (PI_STATUS_DMA_BUSY | PI_STATUS_IO_BUSY)) + cpu_relax(); +} + +/* + * Process a single bvec of a bio. + */ +static bool n64cart_do_bvec(struct device *dev, struct bio_vec *bv, u32 pos) +{ + dma_addr_t dma_addr; + const u32 bstart = pos + start; + + /* Alignment check */ + WARN_ON_ONCE((bv->bv_offset & (MIN_ALIGNMENT - 1)) || + (bv->bv_len & (MIN_ALIGNMENT - 1))); + + dma_addr = dma_map_bvec(dev, bv, DMA_FROM_DEVICE, 0); + if (dma_mapping_error(dev, dma_addr)) + return false; + + n64cart_wait_dma(); + + n64cart_write_reg(PI_DRAM_REG, dma_addr + bv->bv_offset); + n64cart_write_reg(PI_CART_REG, (bstart | CART_DOMAIN) & CART_MAX); + n64cart_write_reg(PI_WRITE_REG, bv->bv_len - 1); + + n64cart_wait_dma(); + + dma_unmap_page(dev, dma_addr, bv->bv_len, DMA_FROM_DEVICE); + return true; +} + +static blk_qc_t n64cart_submit_bio(struct bio *bio) +{ + struct bio_vec bvec; + u32 pos; + struct bvec_iter iter; + + pos = bio->bi_iter.bi_sector << SECTOR_SHIFT; + + bio_for_each_segment(bvec, bio, iter) { + if (!n64cart_do_bvec(dev, &bvec, pos)) + goto io_error; + pos += bvec.bv_len; + } + + bio_endio(bio); + return BLK_QC_T_NONE; +io_error: + bio_io_error(bio); + return BLK_QC_T_NONE; +} + +static const struct block_device_operations n64cart_fops = { + .owner = THIS_MODULE, + .submit_bio = n64cart_submit_bio, +}; + +/* + * The target device is embedded and RAM-constrained. We save RAM + * by initializing in __init code that gets dropped late in boot. + * For the same reason there is no module or unloading support. + */ +static int __init n64cart_probe(struct platform_device *pdev) +{ + int err; + struct request_queue *queue; + struct gendisk *disk; + + if (!start || !size) { + pr_err("n64cart: start and size not specified\n"); + return -ENODEV; + } + + if (size & 4095) { + pr_err("n64cart: size must be a multiple of 4K\n"); + return -ENODEV; + } + + queue = blk_alloc_queue(NUMA_NO_NODE); + if (!queue) { + return -ENOMEM; + } + + reg_base = devm_platform_ioremap_resource(pdev, 0); + if (!reg_base) { + err = -EINVAL; + goto fail_queue; + } + + disk = alloc_disk(0); + if (!disk) { + err = -ENOMEM; + goto fail_queue; + } + + dev = &pdev->dev; + + disk->first_minor = 0; + disk->queue = queue; + disk->flags = GENHD_FL_NO_PART_SCAN | GENHD_FL_EXT_DEVT; + disk->fops = &n64cart_fops; + strcpy(disk->disk_name, "n64cart"); + + set_capacity(disk, size / 512); + set_disk_ro(disk, 1); + + blk_queue_flag_set(QUEUE_FLAG_NONROT, queue); + blk_queue_physical_block_size(queue, 4096); + blk_queue_logical_block_size(queue, 4096); + + add_disk(disk); + + pr_info("n64cart: %u kb disk\n", size / 1024); + + return 0; +fail_queue: + blk_cleanup_queue(queue); + + return err; +} + +static struct platform_driver n64cart_driver = { + .driver = { + .name = "n64cart", + }, +}; + +static int __init n64cart_init(void) +{ + return platform_driver_probe(&n64cart_driver, n64cart_probe); +} + +module_param(start, uint, 0); +MODULE_PARM_DESC(start, "Start address of the cart block data"); + +module_param(size, uint, 0); +MODULE_PARM_DESC(size, "Size of the cart block data, in bytes"); + +module_init(n64cart_init);