Subject: [PATCH 20/20] ARM: pxa: remove old DMA implementation

From: [email-masked] (Daniel Mack)
Date: Wed, 7 Aug 2013 17:34:09 +0200

Signed-off-by: Daniel Mack <[email-masked]>
---
 arch/arm/mach-pxa/include/mach/dma.h |  21 --
 arch/arm/plat-pxa/Makefile           |   2 -
 arch/arm/plat-pxa/dma.c              | 391 -----------------------------------
 arch/arm/plat-pxa/include/plat/dma.h |  85 --------
 4 files changed, 499 deletions(-)
 delete mode 100644 arch/arm/mach-pxa/include/mach/dma.h
 delete mode 100644 arch/arm/plat-pxa/dma.c
 delete mode 100644 arch/arm/plat-pxa/include/plat/dma.h

diff --git a/arch/arm/mach-pxa/include/mach/dma.h b/arch/arm/mach-pxa/include/mach/dma.h
deleted file mode 100644
index 5bd5589..0000000
--- a/arch/arm/mach-pxa/include/mach/dma.h
+++ /dev/null
@@ -1,21 +0,0 @@
-/*
- *  arch/arm/mach-pxa/include/mach/dma.h
- *
- *  Author:	Nicolas Pitre
- *  Created:	Jun 15, 2001
- *  Copyright:	MontaVista Software, Inc.
- *
- * 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.
- */
-#ifndef __ASM_ARCH_DMA_H
-#define __ASM_ARCH_DMA_H
-
-#include <mach/hardware.h>
-
-/* DMA Controller Registers Definitions */
-#define DMAC_REGS_VIRT	io_p2v(0x40000000)
-
-#include <plat/dma.h>
-#endif /* _ASM_ARCH_DMA_H */
diff --git a/arch/arm/plat-pxa/Makefile b/arch/arm/plat-pxa/Makefile
index 1fc9419..826ef87 100644
--- a/arch/arm/plat-pxa/Makefile
+++ b/arch/arm/plat-pxa/Makefile
@@ -2,8 +2,6 @@
 # Makefile for code common across different PXA processor families
 #
 
-obj-y	:= dma.o
-
 obj-$(CONFIG_PXA3xx)		+= mfp.o
 obj-$(CONFIG_ARCH_MMP)		+= mfp.o
 
diff --git a/arch/arm/plat-pxa/dma.c b/arch/arm/plat-pxa/dma.c
deleted file mode 100644
index 79ef102..0000000
--- a/arch/arm/plat-pxa/dma.c
+++ /dev/null
@@ -1,391 +0,0 @@
-/*
- *  linux/arch/arm/plat-pxa/dma.c
- *
- *  PXA DMA registration and IRQ dispatching
- *
- *  Author:	Nicolas Pitre
- *  Created:	Nov 15, 2001
- *  Copyright:	MontaVista Software Inc.
- *
- *  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/module.h>
-#include <linux/init.h>
-#include <linux/slab.h>
-#include <linux/kernel.h>
-#include <linux/interrupt.h>
-#include <linux/errno.h>
-#include <linux/dma-mapping.h>
-
-#include <asm/irq.h>
-#include <asm/memory.h>
-#include <mach/hardware.h>
-#include <mach/dma.h>
-
-#define DMA_DEBUG_NAME		"pxa_dma"
-#define DMA_MAX_REQUESTERS	64
-
-struct dma_channel {
-	char *name;
-	pxa_dma_prio prio;
-	void (*irq_handler)(int, void *);
-	void *data;
-	spinlock_t lock;
-};
-
-static struct dma_channel *dma_channels;
-static int num_dma_channels;
-
-/*
- * Debug fs
- */
-#ifdef CONFIG_DEBUG_FS
-#include <linux/debugfs.h>
-#include <linux/uaccess.h>
-#include <linux/seq_file.h>
-
-static struct dentry *dbgfs_root, *dbgfs_state, **dbgfs_chan;
-
-static int dbg_show_requester_chan(struct seq_file *s, void *p)
-{
-	int pos = 0;
-	int chan = (int)s->private;
-	int i;
-	u32 drcmr;
-
-	pos += seq_printf(s, "DMA channel %d requesters list :\n", chan);
-	for (i = 0; i < DMA_MAX_REQUESTERS; i++) {
-		drcmr = DRCMR(i);
-		if ((drcmr & DRCMR_CHLNUM) == chan)
-			pos += seq_printf(s, "\tRequester %d (MAPVLD=%d)\n", i,
-					  !!(drcmr & DRCMR_MAPVLD));
-	}
-	return pos;
-}
-
-static inline int dbg_burst_from_dcmd(u32 dcmd)
-{
-	int burst = (dcmd >> 16) & 0x3;
-
-	return burst ? 4 << burst : 0;
-}
-
-static int is_phys_valid(unsigned long addr)
-{
-	return pfn_valid(__phys_to_pfn(addr));
-}
-
-#define DCSR_STR(flag) (dcsr & DCSR_##flag ? #flag" " : "")
-#define DCMD_STR(flag) (dcmd & DCMD_##flag ? #flag" " : "")
-
-static int dbg_show_descriptors(struct seq_file *s, void *p)
-{
-	int pos = 0;
-	int chan = (int)s->private;
-	int i, max_show = 20, burst, width;
-	u32 dcmd;
-	unsigned long phys_desc;
-	struct pxa_dma_desc *desc;
-	unsigned long flags;
-
-	spin_lock_irqsave(&dma_channels[chan].lock, flags);
-	phys_desc = DDADR(chan);
-
-	pos += seq_printf(s, "DMA channel %d descriptors :\n", chan);
-	pos += seq_printf(s, "[%03d] First descriptor unknown\n", 0);
-	for (i = 1; i < max_show && is_phys_valid(phys_desc); i++) {
-		desc = phys_to_virt(phys_desc);
-		dcmd = desc->dcmd;
-		burst = dbg_burst_from_dcmd(dcmd);
-		width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
-
-		pos += seq_printf(s, "[%03d] Desc at %08lx(virt %p)\n",
-				  i, phys_desc, desc);
-		pos += seq_printf(s, "\tDDADR = %08x\n", desc->ddadr);
-		pos += seq_printf(s, "\tDSADR = %08x\n", desc->dsadr);
-		pos += seq_printf(s, "\tDTADR = %08x\n", desc->dtadr);
-		pos += seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d"
-				  " width=%d len=%d)\n",
-				  dcmd,
-				  DCMD_STR(INCSRCADDR), DCMD_STR(INCTRGADDR),
-				  DCMD_STR(FLOWSRC), DCMD_STR(FLOWTRG),
-				  DCMD_STR(STARTIRQEN), DCMD_STR(ENDIRQEN),
-				  DCMD_STR(ENDIAN), burst, width,
-				  dcmd & DCMD_LENGTH);
-		phys_desc = desc->ddadr;
-	}
-	if (i == max_show)
-		pos += seq_printf(s, "[%03d] Desc at %08lx ... max display reached\n",
-				  i, phys_desc);
-	else
-		pos += seq_printf(s, "[%03d] Desc at %08lx is %s\n",
-				  i, phys_desc, phys_desc == DDADR_STOP ?
-				  "DDADR_STOP" : "invalid");
-
-	spin_unlock_irqrestore(&dma_channels[chan].lock, flags);
-	return pos;
-}
-
-static int dbg_show_chan_state(struct seq_file *s, void *p)
-{
-	int pos = 0;
-	int chan = (int)s->private;
-	u32 dcsr, dcmd;
-	int burst, width;
-	static char *str_prio[] = { "high", "normal", "low" };
-
-	dcsr = DCSR(chan);
-	dcmd = DCMD(chan);
-	burst = dbg_burst_from_dcmd(dcmd);
-	width = (1 << ((dcmd >> 14) & 0x3)) >> 1;
-
-	pos += seq_printf(s, "DMA channel %d\n", chan);
-	pos += seq_printf(s, "\tPriority : %s\n",
-			  str_prio[dma_channels[chan].prio]);
-	pos += seq_printf(s, "\tUnaligned transfer bit: %s\n",
-			  DALGN & (1 << chan) ? "yes" : "no");
-	pos += seq_printf(s, "\tDCSR  = %08x (%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s)\n",
-			  dcsr, DCSR_STR(RUN), DCSR_STR(NODESC),
-			  DCSR_STR(STOPIRQEN), DCSR_STR(EORIRQEN),
-			  DCSR_STR(EORJMPEN), DCSR_STR(EORSTOPEN),
-			  DCSR_STR(SETCMPST), DCSR_STR(CLRCMPST),
-			  DCSR_STR(CMPST), DCSR_STR(EORINTR), DCSR_STR(REQPEND),
-			  DCSR_STR(STOPSTATE), DCSR_STR(ENDINTR),
-			  DCSR_STR(STARTINTR), DCSR_STR(BUSERR));
-
-	pos += seq_printf(s, "\tDCMD  = %08x (%s%s%s%s%s%s%sburst=%d width=%d"
-			  " len=%d)\n",
-			  dcmd,
-			  DCMD_STR(INCSRCADDR), DCMD_STR(INCTRGADDR),
-			  DCMD_STR(FLOWSRC), DCMD_STR(FLOWTRG),
-			  DCMD_STR(STARTIRQEN), DCMD_STR(ENDIRQEN),
-			  DCMD_STR(ENDIAN), burst, width, dcmd & DCMD_LENGTH);
-	pos += seq_printf(s, "\tDSADR = %08x\n", DSADR(chan));
-	pos += seq_printf(s, "\tDTADR = %08x\n", DTADR(chan));
-	pos += seq_printf(s, "\tDDADR = %08x\n", DDADR(chan));
-	return pos;
-}
-
-static int dbg_show_state(struct seq_file *s, void *p)
-{
-	int pos = 0;
-
-	/* basic device status */
-	pos += seq_printf(s, "DMA engine status\n");
-	pos += seq_printf(s, "\tChannel number: %d\n", num_dma_channels);
-
-	return pos;
-}
-
-#define DBGFS_FUNC_DECL(name) \
-static int dbg_open_##name(struct inode *inode, struct file *file) \
-{ \
-	return single_open(file, dbg_show_##name, inode->i_private); \
-} \
-static const struct file_operations dbg_fops_##name = { \
-	.owner		= THIS_MODULE, \
-	.open		= dbg_open_##name, \
-	.llseek		= seq_lseek, \
-	.read		= seq_read, \
-	.release	= single_release, \
-}
-
-DBGFS_FUNC_DECL(state);
-DBGFS_FUNC_DECL(chan_state);
-DBGFS_FUNC_DECL(descriptors);
-DBGFS_FUNC_DECL(requester_chan);
-
-static struct dentry *pxa_dma_dbg_alloc_chan(int ch, struct dentry *chandir)
-{
-	char chan_name[11];
-	struct dentry *chan, *chan_state = NULL, *chan_descr = NULL;
-	struct dentry *chan_reqs = NULL;
-	void *dt;
-
-	scnprintf(chan_name, sizeof(chan_name), "%d", ch);
-	chan = debugfs_create_dir(chan_name, chandir);
-	dt = (void *)ch;
-
-	if (chan)
-		chan_state = debugfs_create_file("state", 0400, chan, dt,
-						 &dbg_fops_chan_state);
-	if (chan_state)
-		chan_descr = debugfs_create_file("descriptors", 0400, chan, dt,
-						 &dbg_fops_descriptors);
-	if (chan_descr)
-		chan_reqs = debugfs_create_file("requesters", 0400, chan, dt,
-						&dbg_fops_requester_chan);
-	if (!chan_reqs)
-		goto err_state;
-
-	return chan;
-
-err_state:
-	debugfs_remove_recursive(chan);
-	return NULL;
-}
-
-static void pxa_dma_init_debugfs(void)
-{
-	int i;
-	struct dentry *chandir;
-
-	dbgfs_root = debugfs_create_dir(DMA_DEBUG_NAME, NULL);
-	if (IS_ERR(dbgfs_root) || !dbgfs_root)
-		goto err_root;
-
-	dbgfs_state = debugfs_create_file("state", 0400, dbgfs_root, NULL,
-					  &dbg_fops_state);
-	if (!dbgfs_state)
-		goto err_state;
-
-	dbgfs_chan = kmalloc(sizeof(*dbgfs_state) * num_dma_channels,
-			     GFP_KERNEL);
-	if (!dbgfs_chan)
-		goto err_alloc;
-
-	chandir = debugfs_create_dir("channels", dbgfs_root);
-	if (!chandir)
-		goto err_chandir;
-
-	for (i = 0; i < num_dma_channels; i++) {
-		dbgfs_chan[i] = pxa_dma_dbg_alloc_chan(i, chandir);
-		if (!dbgfs_chan[i])
-			goto err_chans;
-	}
-
-	return;
-err_chans:
-err_chandir:
-	kfree(dbgfs_chan);
-err_alloc:
-err_state:
-	debugfs_remove_recursive(dbgfs_root);
-err_root:
-	pr_err("pxa_dma: debugfs is not available\n");
-}
-
-static void __exit pxa_dma_cleanup_debugfs(void)
-{
-	debugfs_remove_recursive(dbgfs_root);
-}
-#else
-static inline void pxa_dma_init_debugfs(void) {}
-static inline void pxa_dma_cleanup_debugfs(void) {}
-#endif
-
-int pxa_request_dma (char *name, pxa_dma_prio prio,
-			void (*irq_handler)(int, void *),
-			void *data)
-{
-	unsigned long flags;
-	int i, found = 0;
-
-	/* basic sanity checks */
-	if (!name || !irq_handler)
-		return -EINVAL;
-
-	local_irq_save(flags);
-
-	do {
-		/* try grabbing a DMA channel with the requested priority */
-		for (i = 0; i < num_dma_channels; i++) {
-			if ((dma_channels[i].prio == prio) &&
-			    !dma_channels[i].name) {
-				found = 1;
-				break;
-			}
-		}
-		/* if requested prio group is full, try a hier priority */
-	} while (!found && prio--);
-
-	if (found) {
-		DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
-		dma_channels[i].name = name;
-		dma_channels[i].irq_handler = irq_handler;
-		dma_channels[i].data = data;
-	} else {
-		printk (KERN_WARNING "No more available DMA channels for %s\n", name);
-		i = -ENODEV;
-	}
-
-	local_irq_restore(flags);
-	return i;
-}
-EXPORT_SYMBOL(pxa_request_dma);
-
-void pxa_free_dma (int dma_ch)
-{
-	unsigned long flags;
-
-	if (!dma_channels[dma_ch].name) {
-		printk (KERN_CRIT
-			"%s: trying to free channel %d which is already freed\n",
-			__func__, dma_ch);
-		return;
-	}
-
-	local_irq_save(flags);
-	DCSR(dma_ch) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
-	dma_channels[dma_ch].name = NULL;
-	local_irq_restore(flags);
-}
-EXPORT_SYMBOL(pxa_free_dma);
-
-static irqreturn_t dma_irq_handler(int irq, void *dev_id)
-{
-	int i, dint = DINT;
-	struct dma_channel *channel;
-
-	while (dint) {
-		i = __ffs(dint);
-		dint &= (dint - 1);
-		channel = &dma_channels[i];
-		if (channel->name && channel->irq_handler) {
-			channel->irq_handler(i, channel->data);
-		} else {
-			/*
-			 * IRQ for an unregistered DMA channel:
-			 * let's clear the interrupts and disable it.
-			 */
-			printk (KERN_WARNING "spurious IRQ for DMA channel %d\n", i);
-			DCSR(i) = DCSR_STARTINTR|DCSR_ENDINTR|DCSR_BUSERR;
-		}
-	}
-	return IRQ_HANDLED;
-}
-
-int __init pxa_init_dma(int irq, int num_ch)
-{
-	int i, ret;
-
-	dma_channels = kzalloc(sizeof(struct dma_channel) * num_ch, GFP_KERNEL);
-	if (dma_channels == NULL)
-		return -ENOMEM;
-
-	/* dma channel priorities on pxa2xx processors:
-	 * ch 0 - 3,  16 - 19  <--> (0) DMA_PRIO_HIGH
-	 * ch 4 - 7,  20 - 23  <--> (1) DMA_PRIO_MEDIUM
-	 * ch 8 - 15, 24 - 31  <--> (2) DMA_PRIO_LOW
-	 */
-	for (i = 0; i < num_ch; i++) {
-		DCSR(i) = 0;
-		dma_channels[i].prio = min((i & 0xf) >> 2, DMA_PRIO_LOW);
-		spin_lock_init(&dma_channels[i].lock);
-	}
-
-	ret = request_irq(irq, dma_irq_handler, IRQF_DISABLED, "DMA", NULL);
-	if (ret) {
-		printk (KERN_CRIT "Wow!  Can't register IRQ for DMA\n");
-		kfree(dma_channels);
-		return ret;
-	}
-	num_dma_channels = num_ch;
-
-	pxa_dma_init_debugfs();
-
-	return 0;
-}
diff --git a/arch/arm/plat-pxa/include/plat/dma.h b/arch/arm/plat-pxa/include/plat/dma.h
deleted file mode 100644
index a7b91dc..0000000
--- a/arch/arm/plat-pxa/include/plat/dma.h
+++ /dev/null
@@ -1,85 +0,0 @@
-#ifndef __PLAT_DMA_H
-#define __PLAT_DMA_H
-
-#define DMAC_REG(x)	(*((volatile u32 *)(DMAC_REGS_VIRT + (x))))
-
-#define DCSR(n)		DMAC_REG((n) << 2)
-#define DALGN		DMAC_REG(0x00a0)  /* DMA Alignment Register */
-#define DINT		DMAC_REG(0x00f0)  /* DMA Interrupt Register */
-#define DDADR(n)	DMAC_REG(0x0200 + ((n) << 4))
-#define DSADR(n)	DMAC_REG(0x0204 + ((n) << 4))
-#define DTADR(n)	DMAC_REG(0x0208 + ((n) << 4))
-#define DCMD(n)		DMAC_REG(0x020c + ((n) << 4))
-#define DRCMR(n)	DMAC_REG((((n) < 64) ? 0x0100 : 0x1100) + \
-				 (((n) & 0x3f) << 2))
-
-#define DCSR_RUN	(1 << 31)	/* Run Bit (read / write) */
-#define DCSR_NODESC	(1 << 30)	/* No-Descriptor Fetch (read / write) */
-#define DCSR_STOPIRQEN	(1 << 29)	/* Stop Interrupt Enable (read / write) */
-#define DCSR_REQPEND	(1 << 8)	/* Request Pending (read-only) */
-#define DCSR_STOPSTATE	(1 << 3)	/* Stop State (read-only) */
-#define DCSR_ENDINTR	(1 << 2)	/* End Interrupt (read / write) */
-#define DCSR_STARTINTR	(1 << 1)	/* Start Interrupt (read / write) */
-#define DCSR_BUSERR	(1 << 0)	/* Bus Error Interrupt (read / write) */
-
-#define DCSR_EORIRQEN	(1 << 28)       /* End of Receive Interrupt Enable (R/W) */
-#define DCSR_EORJMPEN	(1 << 27)       /* Jump to next descriptor on EOR */
-#define DCSR_EORSTOPEN	(1 << 26)       /* STOP on an EOR */
-#define DCSR_SETCMPST	(1 << 25)       /* Set Descriptor Compare Status */
-#define DCSR_CLRCMPST	(1 << 24)       /* Clear Descriptor Compare Status */
-#define DCSR_CMPST	(1 << 10)       /* The Descriptor Compare Status */
-#define DCSR_EORINTR	(1 << 9)        /* The end of Receive */
-
-#define DRCMR_MAPVLD	(1 << 7)	/* Map Valid (read / write) */
-#define DRCMR_CHLNUM	0x1f		/* mask for Channel Number (read / write) */
-
-#define DDADR_DESCADDR	0xfffffff0	/* Address of next descriptor (mask) */
-#define DDADR_STOP	(1 << 0)	/* Stop (read / write) */
-
-#define DCMD_INCSRCADDR	(1 << 31)	/* Source Address Increment Setting. */
-#define DCMD_INCTRGADDR	(1 << 30)	/* Target Address Increment Setting. */
-#define DCMD_FLOWSRC	(1 << 29)	/* Flow Control by the source. */
-#define DCMD_FLOWTRG	(1 << 28)	/* Flow Control by the target. */
-#define DCMD_STARTIRQEN	(1 << 22)	/* Start Interrupt Enable */
-#define DCMD_ENDIRQEN	(1 << 21)	/* End Interrupt Enable */
-#define DCMD_ENDIAN	(1 << 18)	/* Device Endian-ness. */
-#define DCMD_BURST8	(1 << 16)	/* 8 byte burst */
-#define DCMD_BURST16	(2 << 16)	/* 16 byte burst */
-#define DCMD_BURST32	(3 << 16)	/* 32 byte burst */
-#define DCMD_WIDTH1	(1 << 14)	/* 1 byte width */
-#define DCMD_WIDTH2	(2 << 14)	/* 2 byte width (HalfWord) */
-#define DCMD_WIDTH4	(3 << 14)	/* 4 byte width (Word) */
-#define DCMD_LENGTH	0x01fff		/* length mask (max = 8K - 1) */
-
-/*
- * Descriptor structure for PXA's DMA engine
- * Note: this structure must always be aligned to a 16-byte boundary.
- */
-
-typedef struct pxa_dma_desc {
-	volatile u32 ddadr;	/* Points to the next descriptor + flags */
-	volatile u32 dsadr;	/* DSADR value for the current transfer */
-	volatile u32 dtadr;	/* DTADR value for the current transfer */
-	volatile u32 dcmd;	/* DCMD value for the current transfer */
-} pxa_dma_desc;
-
-typedef enum {
-	DMA_PRIO_HIGH = 0,
-	DMA_PRIO_MEDIUM = 1,
-	DMA_PRIO_LOW = 2
-} pxa_dma_prio;
-
-/*
- * DMA registration
- */
-
-int __init pxa_init_dma(int irq, int num_ch);
-
-int pxa_request_dma (char *name,
-			 pxa_dma_prio prio,
-			 void (*irq_handler)(int, void *),
-			 void *data);
-
-void pxa_free_dma (int dma_ch);
-
-#endif /* __PLAT_DMA_H */
-- 
1.8.3.1