cregit-Linux how code gets into the kernel

Release 4.14 arch/sh/drivers/dma/dma-sh.c

/*
 * arch/sh/drivers/dma/dma-sh.c
 *
 * SuperH On-chip DMAC Support
 *
 * Copyright (C) 2000 Takashi YOSHII
 * Copyright (C) 2003, 2004 Paul Mundt
 * Copyright (C) 2005 Andriy Skulysh
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 */
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/io.h>
#include <mach-dreamcast/mach/dma.h>
#include <asm/dma.h>
#include <asm/dma-register.h>
#include <cpu/dma-register.h>
#include <cpu/dma.h>

/*
 * Define the default configuration for dual address memory-memory transfer.
 * The 0x400 value represents auto-request, external->external.
 */

#define RS_DUAL	(DM_INC | SM_INC | RS_AUTO | TS_INDEX2VAL(XMIT_SZ_32BIT))


static unsigned long dma_find_base(unsigned int chan) { unsigned long base = SH_DMAC_BASE0; #ifdef SH_DMAC_BASE1 if (chan >= 6) base = SH_DMAC_BASE1; #endif return base; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3291.43%133.33%
Nobuhiro Iwamatsu25.71%133.33%
Jamie Lenehan12.86%133.33%
Total35100.00%3100.00%


static unsigned long dma_base_addr(unsigned int chan) { unsigned long base = dma_find_base(chan); /* Normalize offset calculation */ if (chan >= 9) chan -= 6; if (chan >= 4) base += 0x10; return base + (chan * 0x10); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt2958.00%250.00%
Andrew Morton1632.00%125.00%
Nobuhiro Iwamatsu510.00%125.00%
Total50100.00%4100.00%

#ifdef CONFIG_SH_DMA_IRQ_MULTI
static inline unsigned int get_dmte_irq(unsigned int chan) { return chan >= 6 ? DMTE6_IRQ : DMTE0_IRQ; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt1885.71%150.00%
Nobuhiro Iwamatsu314.29%150.00%
Total21100.00%2100.00%

#else static unsigned int dmte_irq_map[] = { DMTE0_IRQ, DMTE0_IRQ + 1, DMTE0_IRQ + 2, DMTE0_IRQ + 3, #ifdef DMTE4_IRQ DMTE4_IRQ, DMTE4_IRQ + 1, #endif #ifdef DMTE6_IRQ DMTE6_IRQ, DMTE6_IRQ + 1, #endif #ifdef DMTE8_IRQ DMTE8_IRQ, DMTE9_IRQ, DMTE10_IRQ, DMTE11_IRQ, #endif };
static inline unsigned int get_dmte_irq(unsigned int chan) { return dmte_irq_map[chan]; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt18100.00%1100.00%
Total18100.00%1100.00%

#endif /* * We determine the correct shift size based off of the CHCR transmit size * for the given channel. Since we know that it will take: * * info->count >> ts_shift[transmit_size] * * iterations to complete the transfer. */ static unsigned int ts_shift[] = TS_SHIFT;
static inline unsigned int calc_xmit_shift(struct dma_channel *chan) { u32 chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR); int cnt = ((chcr & CHCR_TS_LOW_MASK) >> CHCR_TS_LOW_SHIFT) | ((chcr & CHCR_TS_HIGH_MASK) >> CHCR_TS_HIGH_SHIFT); return ts_shift[cnt]; }

Contributors

PersonTokensPropCommitsCommitProp
Guennadi Liakhovetski2238.60%114.29%
Paul Mundt2238.60%457.14%
Andrew Morton1017.54%114.29%
Nobuhiro Iwamatsu35.26%114.29%
Total57100.00%7100.00%

/* * The transfer end interrupt must read the chcr register to end the * hardware interrupt active condition. * Besides that it needs to waken any waiting process, which should handle * setting up the next transfer. */
static irqreturn_t dma_tei(int irq, void *dev_id) { struct dma_channel *chan = dev_id; u32 chcr; chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR); if (!(chcr & CHCR_TE)) return IRQ_NONE; chcr &= ~(CHCR_IE | CHCR_DE); __raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR)); wake_up(&chan->wait_queue); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton4654.12%342.86%
Paul Mundt3136.47%342.86%
Nobuhiro Iwamatsu89.41%114.29%
Total85100.00%7100.00%


static int sh_dmac_request_dma(struct dma_channel *chan) { if (unlikely(!(chan->flags & DMA_TEI_CAPABLE))) return 0; return request_irq(get_dmte_irq(chan->chan), dma_tei, IRQF_SHARED, chan->dev_id, chan); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3061.22%444.44%
Andrew Morton1530.61%333.33%
Nobuhiro Iwamatsu24.08%111.11%
Julia Lawall24.08%111.11%
Total49100.00%9100.00%


static void sh_dmac_free_dma(struct dma_channel *chan) { free_irq(get_dmte_irq(chan->chan), chan); }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton1460.87%266.67%
Paul Mundt939.13%133.33%
Total23100.00%3100.00%


static int sh_dmac_configure_channel(struct dma_channel *chan, unsigned long chcr) { if (!chcr) chcr = RS_DUAL | CHCR_IE; if (chcr & CHCR_IE) { chcr &= ~CHCR_IE; chan->flags |= DMA_TEI_CAPABLE; } else { chan->flags &= ~DMA_TEI_CAPABLE; } __raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR)); chan->flags |= DMA_CONFIGURED; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt4758.75%450.00%
Andrew Morton2430.00%225.00%
Nobuhiro Iwamatsu56.25%112.50%
Manuel Lauss45.00%112.50%
Total80100.00%8100.00%


static void sh_dmac_enable_dma(struct dma_channel *chan) { int irq; u32 chcr; chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR); chcr |= CHCR_DE; if (chan->flags & DMA_TEI_CAPABLE) chcr |= CHCR_IE; __raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR)); if (chan->flags & DMA_TEI_CAPABLE) { irq = get_dmte_irq(chan->chan); enable_irq(irq); } }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt4652.87%450.00%
Andrew Morton3337.93%337.50%
Nobuhiro Iwamatsu89.20%112.50%
Total87100.00%8100.00%


static void sh_dmac_disable_dma(struct dma_channel *chan) { int irq; u32 chcr; if (chan->flags & DMA_TEI_CAPABLE) { irq = get_dmte_irq(chan->chan); disable_irq(irq); } chcr = __raw_readl(dma_base_addr(chan->chan) + CHCR); chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE); __raw_writel(chcr, (dma_base_addr(chan->chan) + CHCR)); }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton4453.66%337.50%
Paul Mundt3036.59%450.00%
Nobuhiro Iwamatsu89.76%112.50%
Total82100.00%8100.00%


static int sh_dmac_xfer_dma(struct dma_channel *chan) { /* * If we haven't pre-configured the channel with special flags, use * the defaults. */ if (unlikely(!(chan->flags & DMA_CONFIGURED))) sh_dmac_configure_channel(chan, 0); sh_dmac_disable_dma(chan); /* * Single-address mode usage note! * * It's important that we don't accidentally write any value to SAR/DAR * (this includes 0) that hasn't been directly specified by the user if * we're in single-address mode. * * In this case, only one address can be defined, anything else will * result in a DMA address error interrupt (at least on the SH-4), * which will subsequently halt the transfer. * * Channel 2 on the Dreamcast is a special case, as this is used for * cascading to the PVR2 DMAC. In this case, we still need to write * SAR and DAR, regardless of value, in order for cascading to work. */ if (chan->sar || (mach_is_dreamcast() && chan->chan == PVR2_CASCADE_CHAN)) __raw_writel(chan->sar, (dma_base_addr(chan->chan) + SAR)); if (chan->dar || (mach_is_dreamcast() && chan->chan == PVR2_CASCADE_CHAN)) __raw_writel(chan->dar, (dma_base_addr(chan->chan) + DAR)); __raw_writel(chan->count >> calc_xmit_shift(chan), (dma_base_addr(chan->chan) + TCR)); sh_dmac_enable_dma(chan); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton9265.71%337.50%
Paul Mundt3323.57%450.00%
Nobuhiro Iwamatsu1510.71%112.50%
Total140100.00%8100.00%


static int sh_dmac_get_dma_residue(struct dma_channel *chan) { if (!(__raw_readl(dma_base_addr(chan->chan) + CHCR) & CHCR_DE)) return 0; return __raw_readl(dma_base_addr(chan->chan) + TCR) << calc_xmit_shift(chan); }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton2650.98%342.86%
Paul Mundt1937.25%342.86%
Nobuhiro Iwamatsu611.76%114.29%
Total51100.00%7100.00%

/* * DMAOR handling */ #if defined(CONFIG_CPU_SUBTYPE_SH7723) || \ defined(CONFIG_CPU_SUBTYPE_SH7724) || \ defined(CONFIG_CPU_SUBTYPE_SH7780) || \ defined(CONFIG_CPU_SUBTYPE_SH7785) #define NR_DMAOR 2 #else #define NR_DMAOR 1 #endif /* * DMAOR bases are broken out amongst channel groups. DMAOR0 manages * channels 0 - 5, DMAOR1 6 - 11 (optional). */ #define dmaor_read_reg(n) __raw_readw(dma_find_base((n)*6)) #define dmaor_write_reg(n, data) __raw_writew(data, dma_find_base(n)*6)
static inline int dmaor_reset(int no) { unsigned long dmaor = dmaor_read_reg(no); /* Try to clear the error flags first, incase they are set */ dmaor &= ~(DMAOR_NMIF | DMAOR_AE); dmaor_write_reg(no, dmaor); dmaor |= DMAOR_INIT; dmaor_write_reg(no, dmaor); /* See if we got an error again */ if ((dmaor_read_reg(no) & (DMAOR_AE | DMAOR_NMIF))) { printk(KERN_ERR "dma-sh: Can't initialize DMAOR.\n"); return -EINVAL; } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt6684.62%150.00%
Nobuhiro Iwamatsu1215.38%150.00%
Total78100.00%2100.00%

/* * DMAE handling */ #ifdef CONFIG_CPU_SH4 #if defined(DMAE1_IRQ) #define NR_DMAE 2 #else #define NR_DMAE 1 #endif static const char *dmae_name[] = { "DMAC Address Error0", "DMAC Address Error1" }; #ifdef CONFIG_SH_DMA_IRQ_MULTI
static inline unsigned int get_dma_error_irq(int n) { return get_dmte_irq(n * 6); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt19100.00%1100.00%
Total19100.00%1100.00%

#else static unsigned int dmae_irq_map[] = { DMAE0_IRQ, #ifdef DMAE1_IRQ DMAE1_IRQ, #endif };
static inline unsigned int get_dma_error_irq(int n) { return dmae_irq_map[n]; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt17100.00%1100.00%
Total17100.00%1100.00%

#endif
static irqreturn_t dma_err(int irq, void *dummy) { int i; for (i = 0; i < NR_DMAOR; i++) dmaor_reset(i); disable_irq(irq); return IRQ_HANDLED; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3583.33%375.00%
Nobuhiro Iwamatsu716.67%125.00%
Total42100.00%4100.00%


static int dmae_irq_init(void) { int n; for (n = 0; n < NR_DMAE; n++) { int i = request_irq(get_dma_error_irq(n), dma_err, IRQF_SHARED, dmae_name[n], (void *)dmae_name[n]); if (unlikely(i < 0)) { printk(KERN_ERR "%s request_irq fail\n", dmae_name[n]); return i; } } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt6072.29%133.33%
Nobuhiro Iwamatsu1518.07%133.33%
Mike Frysinger89.64%133.33%
Total83100.00%3100.00%


static void dmae_irq_free(void) { int n; for (n = 0; n < NR_DMAE; n++) free_irq(get_dma_error_irq(n), NULL); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3088.24%266.67%
Nobuhiro Iwamatsu411.76%133.33%
Total34100.00%3100.00%

#else
static inline int dmae_irq_init(void) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt12100.00%2100.00%
Total12100.00%2100.00%


static void dmae_irq_free(void) { }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt7100.00%1100.00%
Total7100.00%1100.00%

#endif static struct dma_ops sh_dmac_ops = { .request = sh_dmac_request_dma, .free = sh_dmac_free_dma, .get_residue = sh_dmac_get_dma_residue, .xfer = sh_dmac_xfer_dma, .configure = sh_dmac_configure_channel, }; static struct dma_info sh_dmac_info = { .name = "sh_dmac", .nr_channels = CONFIG_NR_ONCHIP_DMA_CHANNELS, .ops = &sh_dmac_ops, .flags = DMAC_CHANNELS_TEI_CAPABLE, };
static int __init sh_dmac_init(void) { struct dma_info *info = &sh_dmac_info; int i, rc; /* * Initialize DMAE, for parts that support it. */ rc = dmae_irq_init(); if (unlikely(rc != 0)) return rc; /* * Initialize DMAOR, and clean up any error flags that may have * been set. */ for (i = 0; i < NR_DMAOR; i++) { rc = dmaor_reset(i); if (unlikely(rc != 0)) return rc; } return register_dmac(info); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt3948.15%450.00%
Andrew Morton2429.63%337.50%
Nobuhiro Iwamatsu1822.22%112.50%
Total81100.00%8100.00%


static void __exit sh_dmac_exit(void) { dmae_irq_free(); unregister_dmac(&sh_dmac_info); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt1794.44%375.00%
Andrew Morton15.56%125.00%
Total18100.00%4100.00%

subsys_initcall(sh_dmac_init); module_exit(sh_dmac_exit); MODULE_AUTHOR("Takashi YOSHII, Paul Mundt, Andriy Skulysh"); MODULE_DESCRIPTION("SuperH On-Chip DMAC Support"); MODULE_LICENSE("GPL");

Overall Contributors

PersonTokensPropCommitsCommitProp
Paul Mundt89360.34%947.37%
Andrew Morton41427.97%315.79%
Nobuhiro Iwamatsu1278.58%15.26%
Guennadi Liakhovetski302.03%15.26%
Mike Frysinger80.54%15.26%
Manuel Lauss40.27%15.26%
Julia Lawall20.14%15.26%
Jamie Lenehan10.07%15.26%
Geert Uytterhoeven10.07%15.26%
Total1480100.00%19100.00%
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.