| /* |
| * OMAP2+ DMA driver |
| * |
| * Copyright (C) 2003 - 2008 Nokia Corporation |
| * Author: Juha Yrjölä <juha.yrjola@nokia.com> |
| * DMA channel linking for 1610 by Samuel Ortiz <samuel.ortiz@nokia.com> |
| * Graphics DMA and LCD DMA graphics tranformations |
| * by Imre Deak <imre.deak@nokia.com> |
| * OMAP2/3 support Copyright (C) 2004-2007 Texas Instruments, Inc. |
| * Some functions based on earlier dma-omap.c Copyright (C) 2001 RidgeRun, Inc. |
| * |
| * Copyright (C) 2009 Texas Instruments |
| * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com> |
| * |
| * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/ |
| * Converted DMA library into platform driver |
| * - G, Manjunath Kondaiah <manjugk@ti.com> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/err.h> |
| #include <linux/io.h> |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/device.h> |
| |
| #include <plat/omap_hwmod.h> |
| #include <plat/omap_device.h> |
| #include <plat/dma.h> |
| |
| #define OMAP2_DMA_STRIDE 0x60 |
| |
| static u32 errata; |
| static u8 dma_stride; |
| |
| static struct omap_dma_dev_attr *d; |
| |
| static enum omap_reg_offsets dma_common_ch_start, dma_common_ch_end; |
| |
| static u16 reg_map[] = { |
| [REVISION] = 0x00, |
| [GCR] = 0x78, |
| [IRQSTATUS_L0] = 0x08, |
| [IRQSTATUS_L1] = 0x0c, |
| [IRQSTATUS_L2] = 0x10, |
| [IRQSTATUS_L3] = 0x14, |
| [IRQENABLE_L0] = 0x18, |
| [IRQENABLE_L1] = 0x1c, |
| [IRQENABLE_L2] = 0x20, |
| [IRQENABLE_L3] = 0x24, |
| [SYSSTATUS] = 0x28, |
| [OCP_SYSCONFIG] = 0x2c, |
| [CAPS_0] = 0x64, |
| [CAPS_2] = 0x6c, |
| [CAPS_3] = 0x70, |
| [CAPS_4] = 0x74, |
| |
| /* Common register offsets */ |
| [CCR] = 0x80, |
| [CLNK_CTRL] = 0x84, |
| [CICR] = 0x88, |
| [CSR] = 0x8c, |
| [CSDP] = 0x90, |
| [CEN] = 0x94, |
| [CFN] = 0x98, |
| [CSEI] = 0xa4, |
| [CSFI] = 0xa8, |
| [CDEI] = 0xac, |
| [CDFI] = 0xb0, |
| [CSAC] = 0xb4, |
| [CDAC] = 0xb8, |
| |
| /* Channel specific register offsets */ |
| [CSSA] = 0x9c, |
| [CDSA] = 0xa0, |
| [CCEN] = 0xbc, |
| [CCFN] = 0xc0, |
| [COLOR] = 0xc4, |
| |
| /* OMAP4 specific registers */ |
| [CDP] = 0xd0, |
| [CNDP] = 0xd4, |
| [CCDN] = 0xd8, |
| }; |
| |
| static void __iomem *dma_base; |
| static inline void dma_write(u32 val, int reg, int lch) |
| { |
| u8 stride; |
| u32 offset; |
| |
| stride = (reg >= dma_common_ch_start) ? dma_stride : 0; |
| offset = reg_map[reg] + (stride * lch); |
| __raw_writel(val, dma_base + offset); |
| } |
| |
| static inline u32 dma_read(int reg, int lch) |
| { |
| u8 stride; |
| u32 offset, val; |
| |
| stride = (reg >= dma_common_ch_start) ? dma_stride : 0; |
| offset = reg_map[reg] + (stride * lch); |
| val = __raw_readl(dma_base + offset); |
| return val; |
| } |
| |
| static inline void omap2_disable_irq_lch(int lch) |
| { |
| u32 val; |
| |
| val = dma_read(IRQENABLE_L0, lch); |
| val &= ~(1 << lch); |
| dma_write(val, IRQENABLE_L0, lch); |
| } |
| |
| static void omap2_clear_dma(int lch) |
| { |
| int i = dma_common_ch_start; |
| |
| for (; i <= dma_common_ch_end; i += 1) |
| dma_write(0, i, lch); |
| } |
| |
| static void omap2_show_dma_caps(void) |
| { |
| u8 revision = dma_read(REVISION, 0) & 0xff; |
| printk(KERN_INFO "OMAP DMA hardware revision %d.%d\n", |
| revision >> 4, revision & 0xf); |
| return; |
| } |
| |
| static u32 configure_dma_errata(void) |
| { |
| |
| /* |
| * Errata applicable for OMAP2430ES1.0 and all omap2420 |
| * |
| * I. |
| * Erratum ID: Not Available |
| * Inter Frame DMA buffering issue DMA will wrongly |
| * buffer elements if packing and bursting is enabled. This might |
| * result in data gets stalled in FIFO at the end of the block. |
| * Workaround: DMA channels must have BUFFERING_DISABLED bit set to |
| * guarantee no data will stay in the DMA FIFO in case inter frame |
| * buffering occurs |
| * |
| * II. |
| * Erratum ID: Not Available |
| * DMA may hang when several channels are used in parallel |
| * In the following configuration, DMA channel hanging can occur: |
| * a. Channel i, hardware synchronized, is enabled |
| * b. Another channel (Channel x), software synchronized, is enabled. |
| * c. Channel i is disabled before end of transfer |
| * d. Channel i is reenabled. |
| * e. Steps 1 to 4 are repeated a certain number of times. |
| * f. A third channel (Channel y), software synchronized, is enabled. |
| * Channel x and Channel y may hang immediately after step 'f'. |
| * Workaround: |
| * For any channel used - make sure NextLCH_ID is set to the value j. |
| */ |
| if (cpu_is_omap2420() || (cpu_is_omap2430() && |
| (omap_type() == OMAP2430_REV_ES1_0))) { |
| |
| SET_DMA_ERRATA(DMA_ERRATA_IFRAME_BUFFERING); |
| SET_DMA_ERRATA(DMA_ERRATA_PARALLEL_CHANNELS); |
| } |
| |
| /* |
| * Erratum ID: i378: OMAP2+: sDMA Channel is not disabled |
| * after a transaction error. |
| * Workaround: SW should explicitely disable the channel. |
| */ |
| if (cpu_class_is_omap2()) |
| SET_DMA_ERRATA(DMA_ERRATA_i378); |
| |
| /* |
| * Erratum ID: i541: sDMA FIFO draining does not finish |
| * If sDMA channel is disabled on the fly, sDMA enters standby even |
| * through FIFO Drain is still in progress |
| * Workaround: Put sDMA in NoStandby more before a logical channel is |
| * disabled, then put it back to SmartStandby right after the channel |
| * finishes FIFO draining. |
| */ |
| if (cpu_is_omap34xx()) |
| SET_DMA_ERRATA(DMA_ERRATA_i541); |
| |
| /* |
| * Erratum ID: i88 : Special programming model needed to disable DMA |
| * before end of block. |
| * Workaround: software must ensure that the DMA is configured in No |
| * Standby mode(DMAx_OCP_SYSCONFIG.MIDLEMODE = "01") |
| */ |
| if (omap_type() == OMAP3430_REV_ES1_0) |
| SET_DMA_ERRATA(DMA_ERRATA_i88); |
| |
| /* |
| * Erratum 3.2/3.3: sometimes 0 is returned if CSAC/CDAC is |
| * read before the DMA controller finished disabling the channel. |
| */ |
| SET_DMA_ERRATA(DMA_ERRATA_3_3); |
| |
| /* |
| * Erratum ID: Not Available |
| * A bug in ROM code leaves IRQ status for channels 0 and 1 uncleared |
| * after secure sram context save and restore. |
| * Work around: Hence we need to manually clear those IRQs to avoid |
| * spurious interrupts. This affects only secure devices. |
| */ |
| if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP)) |
| SET_DMA_ERRATA(DMA_ROMCODE_BUG); |
| |
| return errata; |
| } |
| |
| /* One time initializations */ |
| static int __init omap2_system_dma_init_dev(struct omap_hwmod *oh, void *unused) |
| { |
| struct platform_device *pdev; |
| struct omap_system_dma_plat_info *p; |
| struct resource *mem; |
| char *name = "omap_dma_system"; |
| |
| dma_stride = OMAP2_DMA_STRIDE; |
| dma_common_ch_start = CSDP; |
| |
| p = kzalloc(sizeof(struct omap_system_dma_plat_info), GFP_KERNEL); |
| if (!p) { |
| pr_err("%s: Unable to allocate pdata for %s:%s\n", |
| __func__, name, oh->name); |
| return -ENOMEM; |
| } |
| |
| p->dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr; |
| p->disable_irq_lch = omap2_disable_irq_lch; |
| p->show_dma_caps = omap2_show_dma_caps; |
| p->clear_dma = omap2_clear_dma; |
| p->dma_write = dma_write; |
| p->dma_read = dma_read; |
| |
| p->clear_lch_regs = NULL; |
| |
| p->errata = configure_dma_errata(); |
| |
| pdev = omap_device_build(name, 0, oh, p, sizeof(*p), NULL, 0, 0); |
| kfree(p); |
| if (IS_ERR(pdev)) { |
| pr_err("%s: Can't build omap_device for %s:%s.\n", |
| __func__, name, oh->name); |
| return PTR_ERR(pdev); |
| } |
| |
| mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| if (!mem) { |
| dev_err(&pdev->dev, "%s: no mem resource\n", __func__); |
| return -EINVAL; |
| } |
| dma_base = ioremap(mem->start, resource_size(mem)); |
| if (!dma_base) { |
| dev_err(&pdev->dev, "%s: ioremap fail\n", __func__); |
| return -ENOMEM; |
| } |
| |
| d = oh->dev_attr; |
| d->chan = kzalloc(sizeof(struct omap_dma_lch) * |
| (d->lch_count), GFP_KERNEL); |
| |
| if (!d->chan) { |
| dev_err(&pdev->dev, "%s: kzalloc fail\n", __func__); |
| return -ENOMEM; |
| } |
| |
| /* Check the capabilities register for descriptor loading feature */ |
| if (dma_read(CAPS_0, 0) & DMA_HAS_DESCRIPTOR_CAPS) |
| dma_common_ch_end = CCDN; |
| else |
| dma_common_ch_end = CCFN; |
| |
| return 0; |
| } |
| |
| static int __init omap2_system_dma_init(void) |
| { |
| return omap_hwmod_for_each_by_class("dma", |
| omap2_system_dma_init_dev, NULL); |
| } |
| arch_initcall(omap2_system_dma_init); |