Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Long Cheng | 3055 | 97.85% | 1 | 12.50% |
Guillaume Ranquet | 36 | 1.15% | 3 | 37.50% |
Qilong Zhang | 21 | 0.67% | 1 | 12.50% |
Sascha Hauer | 7 | 0.22% | 1 | 12.50% |
SF Markus Elfring | 2 | 0.06% | 1 | 12.50% |
Liu Shixin | 1 | 0.03% | 1 | 12.50% |
Total | 3122 | 8 |
// SPDX-License-Identifier: GPL-2.0 /* * MediaTek UART APDMA driver. * * Copyright (c) 2019 MediaTek Inc. * Author: Long Cheng <long.cheng@mediatek.com> */ #include <linux/clk.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/iopoll.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/of_dma.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/slab.h> #include <linux/spinlock.h> #include "../virt-dma.h" /* The default number of virtual channel */ #define MTK_UART_APDMA_NR_VCHANS 8 #define VFF_EN_B BIT(0) #define VFF_STOP_B BIT(0) #define VFF_FLUSH_B BIT(0) #define VFF_4G_EN_B BIT(0) /* rx valid size >= vff thre */ #define VFF_RX_INT_EN_B (BIT(0) | BIT(1)) /* tx left size >= vff thre */ #define VFF_TX_INT_EN_B BIT(0) #define VFF_WARM_RST_B BIT(0) #define VFF_RX_INT_CLR_B (BIT(0) | BIT(1)) #define VFF_TX_INT_CLR_B 0 #define VFF_STOP_CLR_B 0 #define VFF_EN_CLR_B 0 #define VFF_INT_EN_CLR_B 0 #define VFF_4G_SUPPORT_CLR_B 0 /* * interrupt trigger level for tx * if threshold is n, no polling is required to start tx. * otherwise need polling VFF_FLUSH. */ #define VFF_TX_THRE(n) (n) /* interrupt trigger level for rx */ #define VFF_RX_THRE(n) ((n) * 3 / 4) #define VFF_RING_SIZE 0xffff /* invert this bit when wrap ring head again */ #define VFF_RING_WRAP 0x10000 #define VFF_INT_FLAG 0x00 #define VFF_INT_EN 0x04 #define VFF_EN 0x08 #define VFF_RST 0x0c #define VFF_STOP 0x10 #define VFF_FLUSH 0x14 #define VFF_ADDR 0x1c #define VFF_LEN 0x24 #define VFF_THRE 0x28 #define VFF_WPT 0x2c #define VFF_RPT 0x30 /* TX: the buffer size HW can read. RX: the buffer size SW can read. */ #define VFF_VALID_SIZE 0x3c /* TX: the buffer size SW can write. RX: the buffer size HW can write. */ #define VFF_LEFT_SIZE 0x40 #define VFF_DEBUG_STATUS 0x50 #define VFF_4G_SUPPORT 0x54 struct mtk_uart_apdmadev { struct dma_device ddev; struct clk *clk; bool support_33bits; unsigned int dma_requests; }; struct mtk_uart_apdma_desc { struct virt_dma_desc vd; dma_addr_t addr; unsigned int avail_len; }; struct mtk_chan { struct virt_dma_chan vc; struct dma_slave_config cfg; struct mtk_uart_apdma_desc *desc; enum dma_transfer_direction dir; void __iomem *base; unsigned int irq; unsigned int rx_status; }; static inline struct mtk_uart_apdmadev * to_mtk_uart_apdma_dev(struct dma_device *d) { return container_of(d, struct mtk_uart_apdmadev, ddev); } static inline struct mtk_chan *to_mtk_uart_apdma_chan(struct dma_chan *c) { return container_of(c, struct mtk_chan, vc.chan); } static inline struct mtk_uart_apdma_desc *to_mtk_uart_apdma_desc (struct dma_async_tx_descriptor *t) { return container_of(t, struct mtk_uart_apdma_desc, vd.tx); } static void mtk_uart_apdma_write(struct mtk_chan *c, unsigned int reg, unsigned int val) { writel(val, c->base + reg); } static unsigned int mtk_uart_apdma_read(struct mtk_chan *c, unsigned int reg) { return readl(c->base + reg); } static void mtk_uart_apdma_desc_free(struct virt_dma_desc *vd) { kfree(container_of(vd, struct mtk_uart_apdma_desc, vd)); } static void mtk_uart_apdma_start_tx(struct mtk_chan *c) { struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(c->vc.chan.device); struct mtk_uart_apdma_desc *d = c->desc; unsigned int wpt, vff_sz; vff_sz = c->cfg.dst_port_window_size; if (!mtk_uart_apdma_read(c, VFF_LEN)) { mtk_uart_apdma_write(c, VFF_ADDR, d->addr); mtk_uart_apdma_write(c, VFF_LEN, vff_sz); mtk_uart_apdma_write(c, VFF_THRE, VFF_TX_THRE(vff_sz)); mtk_uart_apdma_write(c, VFF_WPT, 0); mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B); if (mtkd->support_33bits) mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_EN_B); } mtk_uart_apdma_write(c, VFF_EN, VFF_EN_B); if (mtk_uart_apdma_read(c, VFF_EN) != VFF_EN_B) dev_err(c->vc.chan.device->dev, "Enable TX fail\n"); if (!mtk_uart_apdma_read(c, VFF_LEFT_SIZE)) { mtk_uart_apdma_write(c, VFF_INT_EN, VFF_TX_INT_EN_B); return; } wpt = mtk_uart_apdma_read(c, VFF_WPT); wpt += c->desc->avail_len; if ((wpt & VFF_RING_SIZE) == vff_sz) wpt = (wpt & VFF_RING_WRAP) ^ VFF_RING_WRAP; /* Let DMA start moving data */ mtk_uart_apdma_write(c, VFF_WPT, wpt); /* HW auto set to 0 when left size >= threshold */ mtk_uart_apdma_write(c, VFF_INT_EN, VFF_TX_INT_EN_B); if (!mtk_uart_apdma_read(c, VFF_FLUSH)) mtk_uart_apdma_write(c, VFF_FLUSH, VFF_FLUSH_B); } static void mtk_uart_apdma_start_rx(struct mtk_chan *c) { struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(c->vc.chan.device); struct mtk_uart_apdma_desc *d = c->desc; unsigned int vff_sz; vff_sz = c->cfg.src_port_window_size; if (!mtk_uart_apdma_read(c, VFF_LEN)) { mtk_uart_apdma_write(c, VFF_ADDR, d->addr); mtk_uart_apdma_write(c, VFF_LEN, vff_sz); mtk_uart_apdma_write(c, VFF_THRE, VFF_RX_THRE(vff_sz)); mtk_uart_apdma_write(c, VFF_RPT, 0); mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B); if (mtkd->support_33bits) mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_EN_B); } mtk_uart_apdma_write(c, VFF_INT_EN, VFF_RX_INT_EN_B); mtk_uart_apdma_write(c, VFF_EN, VFF_EN_B); if (mtk_uart_apdma_read(c, VFF_EN) != VFF_EN_B) dev_err(c->vc.chan.device->dev, "Enable RX fail\n"); } static void mtk_uart_apdma_tx_handler(struct mtk_chan *c) { mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B); mtk_uart_apdma_write(c, VFF_INT_EN, VFF_INT_EN_CLR_B); mtk_uart_apdma_write(c, VFF_EN, VFF_EN_CLR_B); } static void mtk_uart_apdma_rx_handler(struct mtk_chan *c) { struct mtk_uart_apdma_desc *d = c->desc; unsigned int len, wg, rg; int cnt; mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B); if (!mtk_uart_apdma_read(c, VFF_VALID_SIZE)) return; mtk_uart_apdma_write(c, VFF_EN, VFF_EN_CLR_B); mtk_uart_apdma_write(c, VFF_INT_EN, VFF_INT_EN_CLR_B); len = c->cfg.src_port_window_size; rg = mtk_uart_apdma_read(c, VFF_RPT); wg = mtk_uart_apdma_read(c, VFF_WPT); cnt = (wg & VFF_RING_SIZE) - (rg & VFF_RING_SIZE); /* * The buffer is ring buffer. If wrap bit different, * represents the start of the next cycle for WPT */ if ((rg ^ wg) & VFF_RING_WRAP) cnt += len; c->rx_status = d->avail_len - cnt; mtk_uart_apdma_write(c, VFF_RPT, wg); } static void mtk_uart_apdma_chan_complete_handler(struct mtk_chan *c) { struct mtk_uart_apdma_desc *d = c->desc; if (d) { list_del(&d->vd.node); vchan_cookie_complete(&d->vd); c->desc = NULL; } } static irqreturn_t mtk_uart_apdma_irq_handler(int irq, void *dev_id) { struct dma_chan *chan = (struct dma_chan *)dev_id; struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); unsigned long flags; spin_lock_irqsave(&c->vc.lock, flags); if (c->dir == DMA_DEV_TO_MEM) mtk_uart_apdma_rx_handler(c); else if (c->dir == DMA_MEM_TO_DEV) mtk_uart_apdma_tx_handler(c); mtk_uart_apdma_chan_complete_handler(c); spin_unlock_irqrestore(&c->vc.lock, flags); return IRQ_HANDLED; } static int mtk_uart_apdma_alloc_chan_resources(struct dma_chan *chan) { struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(chan->device); struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); unsigned int status; int ret; ret = pm_runtime_resume_and_get(mtkd->ddev.dev); if (ret < 0) { pm_runtime_put_noidle(chan->device->dev); return ret; } mtk_uart_apdma_write(c, VFF_ADDR, 0); mtk_uart_apdma_write(c, VFF_THRE, 0); mtk_uart_apdma_write(c, VFF_LEN, 0); mtk_uart_apdma_write(c, VFF_RST, VFF_WARM_RST_B); ret = readx_poll_timeout(readl, c->base + VFF_EN, status, !status, 10, 100); if (ret) goto err_pm; ret = request_irq(c->irq, mtk_uart_apdma_irq_handler, IRQF_TRIGGER_NONE, KBUILD_MODNAME, chan); if (ret < 0) { dev_err(chan->device->dev, "Can't request dma IRQ\n"); ret = -EINVAL; goto err_pm; } if (mtkd->support_33bits) mtk_uart_apdma_write(c, VFF_4G_SUPPORT, VFF_4G_SUPPORT_CLR_B); err_pm: pm_runtime_put_noidle(mtkd->ddev.dev); return ret; } static void mtk_uart_apdma_free_chan_resources(struct dma_chan *chan) { struct mtk_uart_apdmadev *mtkd = to_mtk_uart_apdma_dev(chan->device); struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); free_irq(c->irq, chan); tasklet_kill(&c->vc.task); vchan_free_chan_resources(&c->vc); pm_runtime_put_sync(mtkd->ddev.dev); } static enum dma_status mtk_uart_apdma_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) { struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); enum dma_status ret; ret = dma_cookie_status(chan, cookie, txstate); if (!txstate) return ret; dma_set_residue(txstate, c->rx_status); return ret; } /* * dmaengine_prep_slave_single will call the function. and sglen is 1. * 8250 uart using one ring buffer, and deal with one sg. */ static struct dma_async_tx_descriptor *mtk_uart_apdma_prep_slave_sg (struct dma_chan *chan, struct scatterlist *sgl, unsigned int sglen, enum dma_transfer_direction dir, unsigned long tx_flags, void *context) { struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); struct mtk_uart_apdma_desc *d; if (!is_slave_direction(dir) || sglen != 1) return NULL; /* Now allocate and setup the descriptor */ d = kzalloc(sizeof(*d), GFP_NOWAIT); if (!d) return NULL; d->avail_len = sg_dma_len(sgl); d->addr = sg_dma_address(sgl); c->dir = dir; return vchan_tx_prep(&c->vc, &d->vd, tx_flags); } static void mtk_uart_apdma_issue_pending(struct dma_chan *chan) { struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); struct virt_dma_desc *vd; unsigned long flags; spin_lock_irqsave(&c->vc.lock, flags); if (vchan_issue_pending(&c->vc) && !c->desc) { vd = vchan_next_desc(&c->vc); c->desc = to_mtk_uart_apdma_desc(&vd->tx); if (c->dir == DMA_DEV_TO_MEM) mtk_uart_apdma_start_rx(c); else if (c->dir == DMA_MEM_TO_DEV) mtk_uart_apdma_start_tx(c); } spin_unlock_irqrestore(&c->vc.lock, flags); } static int mtk_uart_apdma_slave_config(struct dma_chan *chan, struct dma_slave_config *config) { struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); memcpy(&c->cfg, config, sizeof(*config)); return 0; } static int mtk_uart_apdma_terminate_all(struct dma_chan *chan) { struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); unsigned long flags; unsigned int status; LIST_HEAD(head); int ret; mtk_uart_apdma_write(c, VFF_FLUSH, VFF_FLUSH_B); ret = readx_poll_timeout(readl, c->base + VFF_FLUSH, status, status != VFF_FLUSH_B, 10, 100); if (ret) dev_err(c->vc.chan.device->dev, "flush: fail, status=0x%x\n", mtk_uart_apdma_read(c, VFF_DEBUG_STATUS)); /* * Stop need 3 steps. * 1. set stop to 1 * 2. wait en to 0 * 3. set stop as 0 */ mtk_uart_apdma_write(c, VFF_STOP, VFF_STOP_B); ret = readx_poll_timeout(readl, c->base + VFF_EN, status, !status, 10, 100); if (ret) dev_err(c->vc.chan.device->dev, "stop: fail, status=0x%x\n", mtk_uart_apdma_read(c, VFF_DEBUG_STATUS)); mtk_uart_apdma_write(c, VFF_STOP, VFF_STOP_CLR_B); mtk_uart_apdma_write(c, VFF_INT_EN, VFF_INT_EN_CLR_B); if (c->dir == DMA_DEV_TO_MEM) mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_RX_INT_CLR_B); else if (c->dir == DMA_MEM_TO_DEV) mtk_uart_apdma_write(c, VFF_INT_FLAG, VFF_TX_INT_CLR_B); synchronize_irq(c->irq); spin_lock_irqsave(&c->vc.lock, flags); vchan_get_all_descriptors(&c->vc, &head); spin_unlock_irqrestore(&c->vc.lock, flags); vchan_dma_desc_free_list(&c->vc, &head); return 0; } static int mtk_uart_apdma_device_pause(struct dma_chan *chan) { struct mtk_chan *c = to_mtk_uart_apdma_chan(chan); unsigned long flags; spin_lock_irqsave(&c->vc.lock, flags); mtk_uart_apdma_write(c, VFF_EN, VFF_EN_CLR_B); mtk_uart_apdma_write(c, VFF_INT_EN, VFF_INT_EN_CLR_B); synchronize_irq(c->irq); spin_unlock_irqrestore(&c->vc.lock, flags); return 0; } static void mtk_uart_apdma_free(struct mtk_uart_apdmadev *mtkd) { while (!list_empty(&mtkd->ddev.channels)) { struct mtk_chan *c = list_first_entry(&mtkd->ddev.channels, struct mtk_chan, vc.chan.device_node); list_del(&c->vc.chan.device_node); tasklet_kill(&c->vc.task); } } static const struct of_device_id mtk_uart_apdma_match[] = { { .compatible = "mediatek,mt6577-uart-dma", }, { /* sentinel */ }, }; MODULE_DEVICE_TABLE(of, mtk_uart_apdma_match); static int mtk_uart_apdma_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct mtk_uart_apdmadev *mtkd; int bit_mask = 32, rc; struct mtk_chan *c; unsigned int i; mtkd = devm_kzalloc(&pdev->dev, sizeof(*mtkd), GFP_KERNEL); if (!mtkd) return -ENOMEM; mtkd->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(mtkd->clk)) { dev_err(&pdev->dev, "No clock specified\n"); rc = PTR_ERR(mtkd->clk); return rc; } if (of_property_read_bool(np, "mediatek,dma-33bits")) mtkd->support_33bits = true; if (mtkd->support_33bits) bit_mask = 33; rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(bit_mask)); if (rc) return rc; dma_cap_set(DMA_SLAVE, mtkd->ddev.cap_mask); mtkd->ddev.device_alloc_chan_resources = mtk_uart_apdma_alloc_chan_resources; mtkd->ddev.device_free_chan_resources = mtk_uart_apdma_free_chan_resources; mtkd->ddev.device_tx_status = mtk_uart_apdma_tx_status; mtkd->ddev.device_issue_pending = mtk_uart_apdma_issue_pending; mtkd->ddev.device_prep_slave_sg = mtk_uart_apdma_prep_slave_sg; mtkd->ddev.device_config = mtk_uart_apdma_slave_config; mtkd->ddev.device_pause = mtk_uart_apdma_device_pause; mtkd->ddev.device_terminate_all = mtk_uart_apdma_terminate_all; mtkd->ddev.src_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE); mtkd->ddev.dst_addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE); mtkd->ddev.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); mtkd->ddev.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT; mtkd->ddev.dev = &pdev->dev; INIT_LIST_HEAD(&mtkd->ddev.channels); mtkd->dma_requests = MTK_UART_APDMA_NR_VCHANS; if (of_property_read_u32(np, "dma-requests", &mtkd->dma_requests)) { dev_info(&pdev->dev, "Using %u as missing dma-requests property\n", MTK_UART_APDMA_NR_VCHANS); } for (i = 0; i < mtkd->dma_requests; i++) { c = devm_kzalloc(mtkd->ddev.dev, sizeof(*c), GFP_KERNEL); if (!c) { rc = -ENODEV; goto err_no_dma; } c->base = devm_platform_ioremap_resource(pdev, i); if (IS_ERR(c->base)) { rc = PTR_ERR(c->base); goto err_no_dma; } c->vc.desc_free = mtk_uart_apdma_desc_free; vchan_init(&c->vc, &mtkd->ddev); rc = platform_get_irq(pdev, i); if (rc < 0) goto err_no_dma; c->irq = rc; } pm_runtime_enable(&pdev->dev); pm_runtime_set_active(&pdev->dev); rc = dma_async_device_register(&mtkd->ddev); if (rc) goto rpm_disable; platform_set_drvdata(pdev, mtkd); /* Device-tree DMA controller registration */ rc = of_dma_controller_register(np, of_dma_xlate_by_chan_id, mtkd); if (rc) goto dma_remove; return rc; dma_remove: dma_async_device_unregister(&mtkd->ddev); rpm_disable: pm_runtime_disable(&pdev->dev); err_no_dma: mtk_uart_apdma_free(mtkd); return rc; } static int mtk_uart_apdma_remove(struct platform_device *pdev) { struct mtk_uart_apdmadev *mtkd = platform_get_drvdata(pdev); of_dma_controller_free(pdev->dev.of_node); mtk_uart_apdma_free(mtkd); dma_async_device_unregister(&mtkd->ddev); pm_runtime_disable(&pdev->dev); return 0; } #ifdef CONFIG_PM_SLEEP static int mtk_uart_apdma_suspend(struct device *dev) { struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev); if (!pm_runtime_suspended(dev)) clk_disable_unprepare(mtkd->clk); return 0; } static int mtk_uart_apdma_resume(struct device *dev) { int ret; struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev); if (!pm_runtime_suspended(dev)) { ret = clk_prepare_enable(mtkd->clk); if (ret) return ret; } return 0; } #endif /* CONFIG_PM_SLEEP */ #ifdef CONFIG_PM static int mtk_uart_apdma_runtime_suspend(struct device *dev) { struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev); clk_disable_unprepare(mtkd->clk); return 0; } static int mtk_uart_apdma_runtime_resume(struct device *dev) { struct mtk_uart_apdmadev *mtkd = dev_get_drvdata(dev); return clk_prepare_enable(mtkd->clk); } #endif /* CONFIG_PM */ static const struct dev_pm_ops mtk_uart_apdma_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(mtk_uart_apdma_suspend, mtk_uart_apdma_resume) SET_RUNTIME_PM_OPS(mtk_uart_apdma_runtime_suspend, mtk_uart_apdma_runtime_resume, NULL) }; static struct platform_driver mtk_uart_apdma_driver = { .probe = mtk_uart_apdma_probe, .remove = mtk_uart_apdma_remove, .driver = { .name = KBUILD_MODNAME, .pm = &mtk_uart_apdma_pm_ops, .of_match_table = of_match_ptr(mtk_uart_apdma_match), }, }; module_platform_driver(mtk_uart_apdma_driver); MODULE_DESCRIPTION("MediaTek UART APDMA Controller Driver"); MODULE_AUTHOR("Long Cheng <long.cheng@mediatek.com>"); MODULE_LICENSE("GPL v2");
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