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 <asm/system.h>
26 #include <asm/hardware.h>
28 #include <asm/dma-mapping.h>
30 #include <asm/mach/dma.h>
31 #include <asm/arch/clock.h>
33 static struct dma_channel {
35 void (*irq_handler) (int, int, void *, struct pt_regs *);
37 struct pnx4008_dma_ll *ll;
41 } dma_channels[MAX_DMA_CHANNELS];
43 static struct ll_pool {
50 static spinlock_t ll_lock = SPIN_LOCK_UNLOCKED;
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 spinlock_t dma_lock = SPIN_LOCK_UNLOCKED;
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 *,
154 struct pt_regs *), void *data)
158 /* basic sanity checks */
159 if (!name || (ch != -1 && !VALID_CHANNEL(ch)))
164 /* try grabbing a DMA channel with the requested priority */
165 for (i = MAX_DMA_CHANNELS - 1; i >= 0; i--) {
166 if (!dma_channels[i].name && (ch == -1 || ch == i)) {
173 dma_increment_usage();
174 dma_channels[i].name = name;
175 dma_channels[i].irq_handler = irq_handler;
176 dma_channels[i].data = data;
177 dma_channels[i].ll = NULL;
178 dma_channels[i].ll_dma = 0;
180 printk(KERN_WARNING "No more available DMA channels for %s\n",
185 pnx4008_dma_unlock();
189 EXPORT_SYMBOL_GPL(pnx4008_request_channel);
191 void pnx4008_free_channel(int ch)
193 if (!dma_channels[ch].name) {
195 "%s: trying to free channel %d which is already freed\n",
201 pnx4008_free_ll(dma_channels[ch].ll_dma, dma_channels[ch].ll);
202 dma_channels[ch].ll = NULL;
203 dma_decrement_usage();
205 dma_channels[ch].name = NULL;
206 pnx4008_dma_unlock();
209 EXPORT_SYMBOL_GPL(pnx4008_free_channel);
211 int pnx4008_config_dma(int ahb_m1_be, int ahb_m2_be, int enable)
213 unsigned long dma_cfg = __raw_readl(DMAC_CONFIG);
217 dma_cfg &= ~(1 << 1);
228 dma_cfg &= ~(1 << 2);
239 dma_cfg &= ~(1 << 0);
249 __raw_writel(dma_cfg, DMAC_CONFIG);
250 pnx4008_dma_unlock();
255 EXPORT_SYMBOL_GPL(pnx4008_config_dma);
257 int pnx4008_dma_pack_control(const struct pnx4008_dma_ch_ctrl * ch_ctrl,
260 int i = 0, dbsize, sbsize, err = 0;
262 if (!ctrl || !ch_ctrl) {
269 switch (ch_ctrl->tc_mask) {
281 switch (ch_ctrl->cacheable) {
292 switch (ch_ctrl->bufferable) {
303 switch (ch_ctrl->priv_mode) {
314 switch (ch_ctrl->di) {
325 switch (ch_ctrl->si) {
336 switch (ch_ctrl->dest_ahb1) {
347 switch (ch_ctrl->src_ahb1) {
358 switch (ch_ctrl->dwidth) {
375 switch (ch_ctrl->swidth) {
392 dbsize = ch_ctrl->dbsize;
393 while (!(dbsize & 1)) {
397 if (ch_ctrl->dbsize != 1 || i > 8 || i == 1) {
405 sbsize = ch_ctrl->sbsize;
406 while (!(sbsize & 1)) {
410 if (ch_ctrl->sbsize != 1 || i > 8 || i == 1) {
418 if (ch_ctrl->tr_size > 0x7ff) {
423 *ctrl |= ch_ctrl->tr_size & 0x7ff;
429 EXPORT_SYMBOL_GPL(pnx4008_dma_pack_control);
431 int pnx4008_dma_parse_control(unsigned long ctrl,
432 struct pnx4008_dma_ch_ctrl * ch_ctrl)
441 ch_ctrl->tr_size = ctrl & 0x7ff;
444 ch_ctrl->sbsize = 1 << (ctrl & 7);
445 if (ch_ctrl->sbsize > 1)
446 ch_ctrl->sbsize <<= 1;
449 ch_ctrl->dbsize = 1 << (ctrl & 7);
450 if (ch_ctrl->dbsize > 1)
451 ch_ctrl->dbsize <<= 1;
456 ch_ctrl->swidth = WIDTH_BYTE;
459 ch_ctrl->swidth = WIDTH_HWORD;
462 ch_ctrl->swidth = WIDTH_WORD;
472 ch_ctrl->dwidth = WIDTH_BYTE;
475 ch_ctrl->dwidth = WIDTH_HWORD;
478 ch_ctrl->dwidth = WIDTH_WORD;
486 ch_ctrl->src_ahb1 = ctrl & 1;
489 ch_ctrl->dest_ahb1 = ctrl & 1;
492 ch_ctrl->si = ctrl & 1;
495 ch_ctrl->di = ctrl & 1;
498 ch_ctrl->priv_mode = ctrl & 1;
501 ch_ctrl->bufferable = ctrl & 1;
504 ch_ctrl->cacheable = ctrl & 1;
507 ch_ctrl->tc_mask = ctrl & 1;
513 EXPORT_SYMBOL_GPL(pnx4008_dma_parse_control);
515 int pnx4008_dma_pack_config(const struct pnx4008_dma_ch_config * ch_cfg,
520 if (!cfg || !ch_cfg) {
527 switch (ch_cfg->halt) {
538 switch (ch_cfg->active) {
549 switch (ch_cfg->lock) {
560 switch (ch_cfg->itc) {
571 switch (ch_cfg->ie) {
582 switch (ch_cfg->flow_cntrl) {
598 case FC_PER2PER_DPER:
610 case FC_PER2PER_SPER:
618 *cfg &= ~(0x1f << 6);
619 *cfg |= ((ch_cfg->dest_per & 0x1f) << 6);
621 *cfg &= ~(0x1f << 1);
622 *cfg |= ((ch_cfg->src_per & 0x1f) << 1);
628 EXPORT_SYMBOL_GPL(pnx4008_dma_pack_config);
630 int pnx4008_dma_parse_config(unsigned long cfg,
631 struct pnx4008_dma_ch_config * ch_cfg)
642 ch_cfg->src_per = cfg & 0x1f;
645 ch_cfg->dest_per = cfg & 0x1f;
650 ch_cfg->flow_cntrl = FC_MEM2MEM_DMA;
653 ch_cfg->flow_cntrl = FC_MEM2PER_DMA;
656 ch_cfg->flow_cntrl = FC_PER2MEM_DMA;
659 ch_cfg->flow_cntrl = FC_PER2PER_DMA;
662 ch_cfg->flow_cntrl = FC_PER2PER_DPER;
665 ch_cfg->flow_cntrl = FC_MEM2PER_PER;
668 ch_cfg->flow_cntrl = FC_PER2MEM_PER;
671 ch_cfg->flow_cntrl = FC_PER2PER_SPER;
675 ch_cfg->ie = cfg & 1;
678 ch_cfg->itc = cfg & 1;
681 ch_cfg->lock = cfg & 1;
684 ch_cfg->active = cfg & 1;
687 ch_cfg->halt = cfg & 1;
693 EXPORT_SYMBOL_GPL(pnx4008_dma_parse_config);
695 void pnx4008_dma_split_head_entry(struct pnx4008_dma_config * config,
696 struct pnx4008_dma_ch_ctrl * ctrl)
698 int new_len = ctrl->tr_size, num_entries = 0;
699 int old_len = new_len;
700 int src_width, dest_width, count = 1;
702 switch (ctrl->swidth) {
716 switch (ctrl->dwidth) {
730 while (new_len > 0x7FF) {
732 new_len = (ctrl->tr_size + num_entries) / (num_entries + 1);
734 if (num_entries != 0) {
735 struct pnx4008_dma_ll *ll = NULL;
736 config->ch_ctrl &= ~0x7ff;
737 config->ch_ctrl |= new_len;
738 if (!config->is_ll) {
740 while (num_entries) {
743 pnx4008_alloc_ll_entry(&config->
748 pnx4008_alloc_ll_entry(&ll->
756 src_width * new_len * count;
758 ll->src_addr = config->src_addr;
762 dest_width * new_len * count;
764 ll->dest_addr = config->dest_addr;
765 ll->ch_ctrl = config->ch_ctrl & 0x7fffffff;
772 struct pnx4008_dma_ll *ll_old = config->ll;
773 unsigned long ll_dma_old = config->ll_dma;
774 while (num_entries) {
777 pnx4008_alloc_ll_entry(&config->
782 pnx4008_alloc_ll_entry(&ll->
790 src_width * new_len * count;
792 ll->src_addr = config->src_addr;
796 dest_width * new_len * count;
798 ll->dest_addr = config->dest_addr;
799 ll->ch_ctrl = config->ch_ctrl & 0x7fffffff;
805 ll->next_dma = ll_dma_old;
808 /* adjust last length/tc */
809 ll->ch_ctrl = config->ch_ctrl & (~0x7ff);
810 ll->ch_ctrl |= old_len - new_len * (count - 1);
811 config->ch_ctrl &= 0x7fffffff;
815 EXPORT_SYMBOL_GPL(pnx4008_dma_split_head_entry);
817 void pnx4008_dma_split_ll_entry(struct pnx4008_dma_ll * cur_ll,
818 struct pnx4008_dma_ch_ctrl * ctrl)
820 int new_len = ctrl->tr_size, num_entries = 0;
821 int old_len = new_len;
822 int src_width, dest_width, count = 1;
824 switch (ctrl->swidth) {
838 switch (ctrl->dwidth) {
852 while (new_len > 0x7FF) {
854 new_len = (ctrl->tr_size + num_entries) / (num_entries + 1);
856 if (num_entries != 0) {
857 struct pnx4008_dma_ll *ll = NULL;
858 cur_ll->ch_ctrl &= ~0x7ff;
859 cur_ll->ch_ctrl |= new_len;
861 while (num_entries) {
864 pnx4008_alloc_ll_entry(&cur_ll->
869 pnx4008_alloc_ll_entry(&ll->
877 src_width * new_len * count;
879 ll->src_addr = cur_ll->src_addr;
883 dest_width * new_len * count;
885 ll->dest_addr = cur_ll->dest_addr;
886 ll->ch_ctrl = cur_ll->ch_ctrl & 0x7fffffff;
893 struct pnx4008_dma_ll *ll_old = cur_ll->next;
894 unsigned long ll_dma_old = cur_ll->next_dma;
895 while (num_entries) {
898 pnx4008_alloc_ll_entry(&cur_ll->
903 pnx4008_alloc_ll_entry(&ll->
911 src_width * new_len * count;
913 ll->src_addr = cur_ll->src_addr;
917 dest_width * new_len * count;
919 ll->dest_addr = cur_ll->dest_addr;
920 ll->ch_ctrl = cur_ll->ch_ctrl & 0x7fffffff;
927 ll->next_dma = ll_dma_old;
930 /* adjust last length/tc */
931 ll->ch_ctrl = cur_ll->ch_ctrl & (~0x7ff);
932 ll->ch_ctrl |= old_len - new_len * (count - 1);
933 cur_ll->ch_ctrl &= 0x7fffffff;
937 EXPORT_SYMBOL_GPL(pnx4008_dma_split_ll_entry);
939 int pnx4008_config_channel(int ch, struct pnx4008_dma_config * config)
941 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
945 __raw_writel(config->src_addr, DMAC_Cx_SRC_ADDR(ch));
946 __raw_writel(config->dest_addr, DMAC_Cx_DEST_ADDR(ch));
949 __raw_writel(config->ll_dma, DMAC_Cx_LLI(ch));
951 __raw_writel(0, DMAC_Cx_LLI(ch));
953 __raw_writel(config->ch_ctrl, DMAC_Cx_CONTROL(ch));
954 __raw_writel(config->ch_cfg, DMAC_Cx_CONFIG(ch));
955 pnx4008_dma_unlock();
961 EXPORT_SYMBOL_GPL(pnx4008_config_channel);
963 int pnx4008_channel_get_config(int ch, struct pnx4008_dma_config * config)
965 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name || !config)
969 config->ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
970 config->ch_ctrl = __raw_readl(DMAC_Cx_CONTROL(ch));
972 config->ll_dma = __raw_readl(DMAC_Cx_LLI(ch));
973 config->is_ll = config->ll_dma ? 1 : 0;
975 config->src_addr = __raw_readl(DMAC_Cx_SRC_ADDR(ch));
976 config->dest_addr = __raw_readl(DMAC_Cx_DEST_ADDR(ch));
977 pnx4008_dma_unlock();
982 EXPORT_SYMBOL_GPL(pnx4008_channel_get_config);
984 int pnx4008_dma_ch_enable(int ch)
986 unsigned long ch_cfg;
988 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
992 ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
994 __raw_writel(ch_cfg, DMAC_Cx_CONFIG(ch));
995 pnx4008_dma_unlock();
1000 EXPORT_SYMBOL_GPL(pnx4008_dma_ch_enable);
1002 int pnx4008_dma_ch_disable(int ch)
1004 unsigned long ch_cfg;
1006 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
1010 ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
1012 __raw_writel(ch_cfg, DMAC_Cx_CONFIG(ch));
1013 pnx4008_dma_unlock();
1018 EXPORT_SYMBOL_GPL(pnx4008_dma_ch_disable);
1020 int pnx4008_dma_ch_enabled(int ch)
1022 unsigned long ch_cfg;
1024 if (!VALID_CHANNEL(ch) || !dma_channels[ch].name)
1028 ch_cfg = __raw_readl(DMAC_Cx_CONFIG(ch));
1029 pnx4008_dma_unlock();
1034 EXPORT_SYMBOL_GPL(pnx4008_dma_ch_enabled);
1036 static irqreturn_t dma_irq_handler(int irq, void *dev_id, struct pt_regs *regs)
1039 unsigned long dint = __raw_readl(DMAC_INT_STAT);
1040 unsigned long tcint = __raw_readl(DMAC_INT_TC_STAT);
1041 unsigned long eint = __raw_readl(DMAC_INT_ERR_STAT);
1042 unsigned long i_bit;
1044 for (i = MAX_DMA_CHANNELS - 1; i >= 0; i--) {
1047 struct dma_channel *channel = &dma_channels[i];
1049 if (channel->name && channel->irq_handler) {
1053 cause |= DMA_ERR_INT;
1055 cause |= DMA_TC_INT;
1056 channel->irq_handler(i, cause, channel->data,
1060 * IRQ for an unregistered DMA channel
1063 "spurious IRQ for DMA channel %d\n", i);
1066 __raw_writel(i_bit, DMAC_INT_TC_CLEAR);
1068 __raw_writel(i_bit, DMAC_INT_ERR_CLEAR);
1074 static int __init pnx4008_dma_init(void)
1078 ret = request_irq(DMA_INT, dma_irq_handler, 0, "DMA", NULL);
1080 printk(KERN_CRIT "Wow! Can't register IRQ for DMA\n");
1084 ll_pool.count = 0x4000 / sizeof(struct pnx4008_dma_ll);
1085 ll_pool.cur = ll_pool.vaddr =
1086 dma_alloc_coherent(NULL, ll_pool.count * sizeof(struct pnx4008_dma_ll),
1087 &ll_pool.dma_addr, GFP_KERNEL);
1089 if (!ll_pool.vaddr) {
1091 free_irq(DMA_INT, NULL);
1095 for (i = 0; i < ll_pool.count - 1; i++) {
1096 void **addr = ll_pool.vaddr + i * sizeof(struct pnx4008_dma_ll);
1097 *addr = (void *)addr + sizeof(struct pnx4008_dma_ll);
1099 *(long *)(ll_pool.vaddr +
1100 (ll_pool.count - 1) * sizeof(struct pnx4008_dma_ll)) =
1101 (long)ll_pool.vaddr;
1103 __raw_writel(1, DMAC_CONFIG);
1108 arch_initcall(pnx4008_dma_init);