2 * linux/arch/arm/mach-pnx4008/dma.c
4 * PNX4008 DMA registration and IRQ dispatching
7 * Copyright: MontaVista Software Inc. (c) 2005
9 * Based on the code from Nicolas Pitre
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/kernel.h>
19 #include <linux/interrupt.h>
20 #include <linux/errno.h>
21 #include <linux/err.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/clk.h>
25 #include <linux/gfp.h>
27 #include <asm/system.h>
28 #include <mach/hardware.h>
30 #include <asm/dma-mapping.h>
31 #include <mach/clock.h>
33 static struct dma_channel {
35 void (*irq_handler) (int, int, void *);
37 struct pnx4008_dma_ll *ll;
41 } dma_channels[MAX_DMA_CHANNELS];
43 static struct ll_pool {
50 static DEFINE_SPINLOCK(ll_lock);
52 struct pnx4008_dma_ll *pnx4008_alloc_ll_entry(dma_addr_t * ll_dma)
54 struct pnx4008_dma_ll *ll = NULL;
57 spin_lock_irqsave(&ll_lock, flags);
58 if (ll_pool.count > 4) { /* can give one more */
59 ll = *(struct pnx4008_dma_ll **) ll_pool.cur;
60 *ll_dma = ll_pool.dma_addr + ((void *)ll - ll_pool.vaddr);
61 *(void **)ll_pool.cur = **(void ***)ll_pool.cur;
62 memset(ll, 0, sizeof(*ll));
65 spin_unlock_irqrestore(&ll_lock, flags);
70 EXPORT_SYMBOL_GPL(pnx4008_alloc_ll_entry);
72 void pnx4008_free_ll_entry(struct pnx4008_dma_ll * ll, dma_addr_t ll_dma)
77 if ((unsigned long)((long)ll - (long)ll_pool.vaddr) > 0x4000) {
78 printk(KERN_ERR "Trying to free entry not allocated by DMA\n");
82 if (ll->flags & DMA_BUFFER_ALLOCATED)
83 ll->free(ll->alloc_data);
85 spin_lock_irqsave(&ll_lock, flags);
86 *(long *)ll = *(long *)ll_pool.cur;
87 *(long *)ll_pool.cur = (long)ll;
89 spin_unlock_irqrestore(&ll_lock, flags);
93 EXPORT_SYMBOL_GPL(pnx4008_free_ll_entry);
95 void pnx4008_free_ll(u32 ll_dma, struct pnx4008_dma_ll * ll)
97 struct pnx4008_dma_ll *ptr;
103 pnx4008_free_ll_entry(ll, ll_dma);
110 EXPORT_SYMBOL_GPL(pnx4008_free_ll);
112 static int dma_channels_requested = 0;
114 static inline void dma_increment_usage(void)
116 if (!dma_channels_requested++) {
117 struct clk *clk = clk_get(0, "dma_ck");
119 clk_set_rate(clk, 1);
122 pnx4008_config_dma(-1, -1, 1);
125 static inline void dma_decrement_usage(void)
127 if (!--dma_channels_requested) {
128 struct clk *clk = clk_get(0, "dma_ck");
130 clk_set_rate(clk, 0);
133 pnx4008_config_dma(-1, -1, 0);
138 static DEFINE_SPINLOCK(dma_lock);
140 static inline void pnx4008_dma_lock(void)
142 spin_lock_irq(&dma_lock);
145 static inline void pnx4008_dma_unlock(void)
147 spin_unlock_irq(&dma_lock);
150 #define VALID_CHANNEL(c) (((c) >= 0) && ((c) < MAX_DMA_CHANNELS))
152 int pnx4008_request_channel(char *name, int ch,
153 void (*irq_handler) (int, int, void *), void *data)
157 /* basic sanity checks */
158 if (!name || (ch != -1 && !VALID_CHANNEL(ch)))
163 /* try grabbing a DMA channel with the requested priority */
164 for (i = MAX_DMA_CHANNELS - 1; i >= 0; i--) {
165 if (!dma_channels[i].name && (ch == -1 || ch == i)) {
172 dma_increment_usage();
173 dma_channels[i].name = name;
174 dma_channels[i].irq_handler = irq_handler;
175 dma_channels[i].data = data;
176 dma_channels[i].ll = NULL;
177 dma_channels[i].ll_dma = 0;
179 printk(KERN_WARNING "No more available DMA channels for %s\n",
184 pnx4008_dma_unlock();
188 EXPORT_SYMBOL_GPL(pnx4008_request_channel);
190 void pnx4008_free_channel(int ch)
192 if (!dma_channels[ch].name) {
194 "%s: trying to free channel %d which is already freed\n",
200 pnx4008_free_ll(dma_channels[ch].ll_dma, dma_channels[ch].ll);
201 dma_channels[ch].ll = NULL;
202 dma_decrement_usage();
204 dma_channels[ch].name = NULL;
205 pnx4008_dma_unlock();
208 EXPORT_SYMBOL_GPL(pnx4008_free_channel);
210 int pnx4008_config_dma(int ahb_m1_be, int ahb_m2_be, int enable)
212 unsigned long dma_cfg = __raw_readl(DMAC_CONFIG);
216 dma_cfg &= ~(1 << 1);
227 dma_cfg &= ~(1 << 2);
238 dma_cfg &= ~(1 << 0);
248 __raw_writel(dma_cfg, DMAC_CONFIG);
249 pnx4008_dma_unlock();
254 EXPORT_SYMBOL_GPL(pnx4008_config_dma);
256 int pnx4008_dma_pack_control(const struct pnx4008_dma_ch_ctrl * ch_ctrl,
259 int i = 0, dbsize, sbsize, err = 0;
261 if (!ctrl || !ch_ctrl) {
268 switch (ch_ctrl->tc_mask) {
280 switch (ch_ctrl->cacheable) {
291 switch (ch_ctrl->bufferable) {
302 switch (ch_ctrl->priv_mode) {
313 switch (ch_ctrl->di) {
324 switch (ch_ctrl->si) {
335 switch (ch_ctrl->dest_ahb1) {
346 switch (ch_ctrl->src_ahb1) {
357 switch (ch_ctrl->dwidth) {
374 switch (ch_ctrl->swidth) {
391 dbsize = ch_ctrl->dbsize;
392 while (!(dbsize & 1)) {
396 if (ch_ctrl->dbsize != 1 || i > 8 || i == 1) {
404 sbsize = ch_ctrl->sbsize;
405 while (!(sbsize & 1)) {
409 if (ch_ctrl->sbsize != 1 || i > 8 || i == 1) {
417 if (ch_ctrl->tr_size > 0x7ff) {
422 *ctrl |= ch_ctrl->tr_size & 0x7ff;
428 EXPORT_SYMBOL_GPL(pnx4008_dma_pack_control);
430 int pnx4008_dma_parse_control(unsigned long ctrl,
431 struct pnx4008_dma_ch_ctrl * ch_ctrl)
440 ch_ctrl->tr_size = ctrl & 0x7ff;
443 ch_ctrl->sbsize = 1 << (ctrl & 7);
444 if (ch_ctrl->sbsize > 1)
445 ch_ctrl->sbsize <<= 1;
448 ch_ctrl->dbsize = 1 << (ctrl & 7);
449 if (ch_ctrl->dbsize > 1)
450 ch_ctrl->dbsize <<= 1;
455 ch_ctrl->swidth = WIDTH_BYTE;
458 ch_ctrl->swidth = WIDTH_HWORD;
461 ch_ctrl->swidth = WIDTH_WORD;
471 ch_ctrl->dwidth = WIDTH_BYTE;
474 ch_ctrl->dwidth = WIDTH_HWORD;
477 ch_ctrl->dwidth = WIDTH_WORD;
485 ch_ctrl->src_ahb1 = ctrl & 1;
488 ch_ctrl->dest_ahb1 = ctrl & 1;
491 ch_ctrl->si = ctrl & 1;
494 ch_ctrl->di = ctrl & 1;
497 ch_ctrl->priv_mode = ctrl & 1;
500 ch_ctrl->bufferable = ctrl & 1;
503 ch_ctrl->cacheable = ctrl & 1;
506 ch_ctrl->tc_mask = ctrl & 1;
512 EXPORT_SYMBOL_GPL(pnx4008_dma_parse_control);
514 int pnx4008_dma_pack_config(const struct pnx4008_dma_ch_config * ch_cfg,
519 if (!cfg || !ch_cfg) {
526 switch (ch_cfg->halt) {
537 switch (ch_cfg->active) {
548 switch (ch_cfg->lock) {
559 switch (ch_cfg->itc) {
570 switch (ch_cfg->ie) {
581 switch (ch_cfg->flow_cntrl) {
597 case FC_PER2PER_DPER:
609 case FC_PER2PER_SPER:
617 *cfg &= ~(0x1f << 6);
618 *cfg |= ((ch_cfg->dest_per & 0x1f) << 6);
620 *cfg &= ~(0x1f << 1);
621 *cfg |= ((ch_cfg->src_per & 0x1f) << 1);
627 EXPORT_SYMBOL_GPL(pnx4008_dma_pack_config);
629 int pnx4008_dma_parse_config(unsigned long cfg,
630 struct pnx4008_dma_ch_config * ch_cfg)
641 ch_cfg->src_per = cfg & 0x1f;
644 ch_cfg->dest_per = cfg & 0x1f;
649 ch_cfg->flow_cntrl = FC_MEM2MEM_DMA;
652 ch_cfg->flow_cntrl = FC_MEM2PER_DMA;
655 ch_cfg->flow_cntrl = FC_PER2MEM_DMA;
658 ch_cfg->flow_cntrl = FC_PER2PER_DMA;
661 ch_cfg->flow_cntrl = FC_PER2PER_DPER;
664 ch_cfg->flow_cntrl = FC_MEM2PER_PER;
667 ch_cfg->flow_cntrl = FC_PER2MEM_PER;
670 ch_cfg->flow_cntrl = FC_PER2PER_SPER;
674 ch_cfg->ie = cfg & 1;
677 ch_cfg->itc = cfg & 1;
680 ch_cfg->lock = cfg & 1;
683 ch_cfg->active = cfg & 1;
686 ch_cfg->halt = cfg & 1;
692 EXPORT_SYMBOL_GPL(pnx4008_dma_parse_config);
694 void pnx4008_dma_split_head_entry(struct pnx4008_dma_config * config,
695 struct pnx4008_dma_ch_ctrl * ctrl)
697 int new_len = ctrl->tr_size, num_entries = 0;
698 int old_len = new_len;
699 int src_width, dest_width, count = 1;
701 switch (ctrl->swidth) {
715 switch (ctrl->dwidth) {
729 while (new_len > 0x7FF) {
731 new_len = (ctrl->tr_size + num_entries) / (num_entries + 1);
733 if (num_entries != 0) {
734 struct pnx4008_dma_ll *ll = NULL;
735 config->ch_ctrl &= ~0x7ff;
736 config->ch_ctrl |= new_len;
737 if (!config->is_ll) {
739 while (num_entries) {
742 pnx4008_alloc_ll_entry(&config->
747 pnx4008_alloc_ll_entry(&ll->
755 src_width * new_len * count;
757 ll->src_addr = config->src_addr;
761 dest_width * new_len * count;
763 ll->dest_addr = config->dest_addr;
764 ll->ch_ctrl = config->ch_ctrl & 0x7fffffff;
771 struct pnx4008_dma_ll *ll_old = config->ll;
772 unsigned long ll_dma_old = config->ll_dma;
773 while (num_entries) {
776 pnx4008_alloc_ll_entry(&config->
781 pnx4008_alloc_ll_entry(&ll->
789 src_width * new_len * count;
791 ll->src_addr = config->src_addr;
795 dest_width * new_len * count;
797 ll->dest_addr = config->dest_addr;
798 ll->ch_ctrl = config->ch_ctrl & 0x7fffffff;
804 ll->next_dma = ll_dma_old;
807 /* adjust last length/tc */
808 ll->ch_ctrl = config->ch_ctrl & (~0x7ff);
809 ll->ch_ctrl |= old_len - new_len * (count - 1);
810 config->ch_ctrl &= 0x7fffffff;
814 EXPORT_SYMBOL_GPL(pnx4008_dma_split_head_entry);
816 void pnx4008_dma_split_ll_entry(struct pnx4008_dma_ll * cur_ll,
817 struct pnx4008_dma_ch_ctrl * ctrl)
819 int new_len = ctrl->tr_size, num_entries = 0;
820 int old_len = new_len;
821 int src_width, dest_width, count = 1;
823 switch (ctrl->swidth) {
837 switch (ctrl->dwidth) {
851 while (new_len > 0x7FF) {
853 new_len = (ctrl->tr_size + num_entries) / (num_entries + 1);
855 if (num_entries != 0) {
856 struct pnx4008_dma_ll *ll = NULL;
857 cur_ll->ch_ctrl &= ~0x7ff;
858 cur_ll->ch_ctrl |= new_len;
860 while (num_entries) {
863 pnx4008_alloc_ll_entry(&cur_ll->
868 pnx4008_alloc_ll_entry(&ll->
876 src_width * new_len * count;
878 ll->src_addr = cur_ll->src_addr;
882 dest_width * new_len * count;
884 ll->dest_addr = cur_ll->dest_addr;
885 ll->ch_ctrl = cur_ll->ch_ctrl & 0x7fffffff;
892 struct pnx4008_dma_ll *ll_old = cur_ll->next;
893 unsigned long ll_dma_old = cur_ll->next_dma;
894 while (num_entries) {
897 pnx4008_alloc_ll_entry(&cur_ll->
902 pnx4008_alloc_ll_entry(&ll->
910 src_width * new_len * count;
912 ll->src_addr = cur_ll->src_addr;
916 dest_width * new_len * count;
918 ll->dest_addr = cur_ll->dest_addr;
919 ll->ch_ctrl = cur_ll->ch_ctrl & 0x7fffffff;
926 ll->next_dma = ll_dma_old;
929 /* adjust last length/tc */
930 ll->ch_ctrl = cur_ll->ch_ctrl & (~0x7ff);
931 ll->ch_ctrl |= old_len - new_len * (count - 1);
932 cur_ll->ch_ctrl &= 0x7fffffff;
936 EXPORT_SYMBOL_GPL(pnx4008_dma_split_ll_entry);
938 int pnx4008_config_channel(int ch, struct pnx4008_dma_config * config)
940 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
944 __raw_writel(config->src_addr, DMAC_Cx_SRC_ADDR(ch));
945 __raw_writel(config->dest_addr, DMAC_Cx_DEST_ADDR(ch));
948 __raw_writel(config->ll_dma, DMAC_Cx_LLI(ch));
950 __raw_writel(0, DMAC_Cx_LLI(ch));
952 __raw_writel(config->ch_ctrl, DMAC_Cx_CONTROL(ch));
953 __raw_writel(config->ch_cfg, DMAC_Cx_CONFIG(ch));
954 pnx4008_dma_unlock();
960 EXPORT_SYMBOL_GPL(pnx4008_config_channel);
962 int pnx4008_channel_get_config(int ch, struct pnx4008_dma_config * config)
964 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name || !config)
968 config->ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
969 config->ch_ctrl = __raw_readl(DMAC_Cx_CONTROL(ch));
971 config->ll_dma = __raw_readl(DMAC_Cx_LLI(ch));
972 config->is_ll = config->ll_dma ? 1 : 0;
974 config->src_addr = __raw_readl(DMAC_Cx_SRC_ADDR(ch));
975 config->dest_addr = __raw_readl(DMAC_Cx_DEST_ADDR(ch));
976 pnx4008_dma_unlock();
981 EXPORT_SYMBOL_GPL(pnx4008_channel_get_config);
983 int pnx4008_dma_ch_enable(int ch)
985 unsigned long ch_cfg;
987 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
991 ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
993 __raw_writel(ch_cfg, DMAC_Cx_CONFIG(ch));
994 pnx4008_dma_unlock();
999 EXPORT_SYMBOL_GPL(pnx4008_dma_ch_enable);
1001 int pnx4008_dma_ch_disable(int ch)
1003 unsigned long ch_cfg;
1005 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
1009 ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
1011 __raw_writel(ch_cfg, DMAC_Cx_CONFIG(ch));
1012 pnx4008_dma_unlock();
1017 EXPORT_SYMBOL_GPL(pnx4008_dma_ch_disable);
1019 int pnx4008_dma_ch_enabled(int ch)
1021 unsigned long ch_cfg;
1023 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
1027 ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
1028 pnx4008_dma_unlock();
1033 EXPORT_SYMBOL_GPL(pnx4008_dma_ch_enabled);
1035 static irqreturn_t dma_irq_handler(int irq, void *dev_id)
1038 unsigned long dint = __raw_readl(DMAC_INT_STAT);
1039 unsigned long tcint = __raw_readl(DMAC_INT_TC_STAT);
1040 unsigned long eint = __raw_readl(DMAC_INT_ERR_STAT);
1041 unsigned long i_bit;
1043 for (i = MAX_DMA_CHANNELS - 1; i >= 0; i--) {
1046 struct dma_channel *channel = &dma_channels[i];
1048 if (channel->name && channel->irq_handler) {
1052 cause |= DMA_ERR_INT;
1054 cause |= DMA_TC_INT;
1055 channel->irq_handler(i, cause, channel->data);
1058 * IRQ for an unregistered DMA channel
1061 "spurious IRQ for DMA channel %d\n", i);
1064 __raw_writel(i_bit, DMAC_INT_TC_CLEAR);
1066 __raw_writel(i_bit, DMAC_INT_ERR_CLEAR);
1072 static int __init pnx4008_dma_init(void)
1076 ret = request_irq(DMA_INT, dma_irq_handler, 0, "DMA", NULL);
1078 printk(KERN_CRIT "Wow! Can't register IRQ for DMA\n");
1082 ll_pool.count = 0x4000 / sizeof(struct pnx4008_dma_ll);
1083 ll_pool.cur = ll_pool.vaddr =
1084 dma_alloc_coherent(NULL, ll_pool.count * sizeof(struct pnx4008_dma_ll),
1085 &ll_pool.dma_addr, GFP_KERNEL);
1087 if (!ll_pool.vaddr) {
1089 free_irq(DMA_INT, NULL);
1093 for (i = 0; i < ll_pool.count - 1; i++) {
1094 void **addr = ll_pool.vaddr + i * sizeof(struct pnx4008_dma_ll);
1095 *addr = (void *)addr + sizeof(struct pnx4008_dma_ll);
1097 *(long *)(ll_pool.vaddr +
1098 (ll_pool.count - 1) * sizeof(struct pnx4008_dma_ll)) =
1099 (long)ll_pool.vaddr;
1101 __raw_writel(1, DMAC_CONFIG);
1106 arch_initcall(pnx4008_dma_init);