diff options
Diffstat (limited to 'kernel/arch/arm/mach-omap2/dma.c')
-rw-r--r-- | kernel/arch/arm/mach-omap2/dma.c | 293 |
1 files changed, 293 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-omap2/dma.c b/kernel/arch/arm/mach-omap2/dma.c new file mode 100644 index 000000000..e1a56d875 --- /dev/null +++ b/kernel/arch/arm/mach-omap2/dma.c @@ -0,0 +1,293 @@ +/* + * 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 <linux/dma-mapping.h> +#include <linux/of.h> +#include <linux/omap-dma.h> + +#include "soc.h" +#include "omap_hwmod.h" +#include "omap_device.h" + +static enum omap_reg_offsets dma_common_ch_end; + +static const struct omap_dma_reg reg_map[] = { + [REVISION] = { 0x0000, 0x00, OMAP_DMA_REG_32BIT }, + [GCR] = { 0x0078, 0x00, OMAP_DMA_REG_32BIT }, + [IRQSTATUS_L0] = { 0x0008, 0x00, OMAP_DMA_REG_32BIT }, + [IRQSTATUS_L1] = { 0x000c, 0x00, OMAP_DMA_REG_32BIT }, + [IRQSTATUS_L2] = { 0x0010, 0x00, OMAP_DMA_REG_32BIT }, + [IRQSTATUS_L3] = { 0x0014, 0x00, OMAP_DMA_REG_32BIT }, + [IRQENABLE_L0] = { 0x0018, 0x00, OMAP_DMA_REG_32BIT }, + [IRQENABLE_L1] = { 0x001c, 0x00, OMAP_DMA_REG_32BIT }, + [IRQENABLE_L2] = { 0x0020, 0x00, OMAP_DMA_REG_32BIT }, + [IRQENABLE_L3] = { 0x0024, 0x00, OMAP_DMA_REG_32BIT }, + [SYSSTATUS] = { 0x0028, 0x00, OMAP_DMA_REG_32BIT }, + [OCP_SYSCONFIG] = { 0x002c, 0x00, OMAP_DMA_REG_32BIT }, + [CAPS_0] = { 0x0064, 0x00, OMAP_DMA_REG_32BIT }, + [CAPS_2] = { 0x006c, 0x00, OMAP_DMA_REG_32BIT }, + [CAPS_3] = { 0x0070, 0x00, OMAP_DMA_REG_32BIT }, + [CAPS_4] = { 0x0074, 0x00, OMAP_DMA_REG_32BIT }, + + /* Common register offsets */ + [CCR] = { 0x0080, 0x60, OMAP_DMA_REG_32BIT }, + [CLNK_CTRL] = { 0x0084, 0x60, OMAP_DMA_REG_32BIT }, + [CICR] = { 0x0088, 0x60, OMAP_DMA_REG_32BIT }, + [CSR] = { 0x008c, 0x60, OMAP_DMA_REG_32BIT }, + [CSDP] = { 0x0090, 0x60, OMAP_DMA_REG_32BIT }, + [CEN] = { 0x0094, 0x60, OMAP_DMA_REG_32BIT }, + [CFN] = { 0x0098, 0x60, OMAP_DMA_REG_32BIT }, + [CSEI] = { 0x00a4, 0x60, OMAP_DMA_REG_32BIT }, + [CSFI] = { 0x00a8, 0x60, OMAP_DMA_REG_32BIT }, + [CDEI] = { 0x00ac, 0x60, OMAP_DMA_REG_32BIT }, + [CDFI] = { 0x00b0, 0x60, OMAP_DMA_REG_32BIT }, + [CSAC] = { 0x00b4, 0x60, OMAP_DMA_REG_32BIT }, + [CDAC] = { 0x00b8, 0x60, OMAP_DMA_REG_32BIT }, + + /* Channel specific register offsets */ + [CSSA] = { 0x009c, 0x60, OMAP_DMA_REG_32BIT }, + [CDSA] = { 0x00a0, 0x60, OMAP_DMA_REG_32BIT }, + [CCEN] = { 0x00bc, 0x60, OMAP_DMA_REG_32BIT }, + [CCFN] = { 0x00c0, 0x60, OMAP_DMA_REG_32BIT }, + [COLOR] = { 0x00c4, 0x60, OMAP_DMA_REG_32BIT }, + + /* OMAP4 specific registers */ + [CDP] = { 0x00d0, 0x60, OMAP_DMA_REG_32BIT }, + [CNDP] = { 0x00d4, 0x60, OMAP_DMA_REG_32BIT }, + [CCDN] = { 0x00d8, 0x60, OMAP_DMA_REG_32BIT }, +}; + +static void __iomem *dma_base; +static inline void dma_write(u32 val, int reg, int lch) +{ + void __iomem *addr = dma_base; + + addr += reg_map[reg].offset; + addr += reg_map[reg].stride * lch; + + writel_relaxed(val, addr); +} + +static inline u32 dma_read(int reg, int lch) +{ + void __iomem *addr = dma_base; + + addr += reg_map[reg].offset; + addr += reg_map[reg].stride * lch; + + return readl_relaxed(addr); +} + +static void omap2_clear_dma(int lch) +{ + int i; + + for (i = CSDP; 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 unsigned configure_dma_errata(void) +{ + unsigned errata = 0; + + /* + * 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; +} + +static struct omap_system_dma_plat_info dma_plat_info __initdata = { + .reg_map = reg_map, + .channel_stride = 0x60, + .show_dma_caps = omap2_show_dma_caps, + .clear_dma = omap2_clear_dma, + .dma_write = dma_write, + .dma_read = dma_read, +}; + +static struct platform_device_info omap_dma_dev_info = { + .name = "omap-dma-engine", + .id = -1, + .dma_mask = DMA_BIT_MASK(32), +}; + +/* 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 omap_dma_dev_attr *d; + struct resource *mem; + char *name = "omap_dma_system"; + + p = dma_plat_info; + p.dma_attr = (struct omap_dma_dev_attr *)oh->dev_attr; + p.errata = configure_dma_errata(); + + pdev = omap_device_build(name, 0, oh, &p, sizeof(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); + } + + omap_dma_dev_info.res = pdev->resource; + omap_dma_dev_info.num_res = pdev->num_resources; + + 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; + + if (cpu_is_omap34xx() && (omap_type() != OMAP2_DEVICE_TYPE_GP)) + d->dev_caps |= HS_CHANNELS_RESERVED; + + if (platform_get_irq_byname(pdev, "0") < 0) + d->dev_caps |= DMA_ENGINE_HANDLE_IRQ; + + /* 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) +{ + struct platform_device *pdev; + int res; + + res = omap_hwmod_for_each_by_class("dma", + omap2_system_dma_init_dev, NULL); + if (res) + return res; + + if (of_have_populated_dt()) + return res; + + pdev = platform_device_register_full(&omap_dma_dev_info); + if (IS_ERR(pdev)) + return PTR_ERR(pdev); + + return res; +} +omap_arch_initcall(omap2_system_dma_init); |