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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/frv/kernel/dma.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/frv/kernel/dma.c')
-rw-r--r--arch/frv/kernel/dma.c464
1 files changed, 464 insertions, 0 deletions
diff --git a/arch/frv/kernel/dma.c b/arch/frv/kernel/dma.c
new file mode 100644
index 00000000000..f5de6cf7df4
--- /dev/null
+++ b/arch/frv/kernel/dma.c
@@ -0,0 +1,464 @@
+/* dma.c: DMA controller management on FR401 and the like
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <asm/dma.h>
+#include <asm/gpio-regs.h>
+#include <asm/irc-regs.h>
+#include <asm/cpu-irqs.h>
+
+struct frv_dma_channel {
+ uint8_t flags;
+#define FRV_DMA_FLAGS_RESERVED 0x01
+#define FRV_DMA_FLAGS_INUSE 0x02
+#define FRV_DMA_FLAGS_PAUSED 0x04
+ uint8_t cap; /* capabilities available */
+ int irq; /* completion IRQ */
+ uint32_t dreqbit;
+ uint32_t dackbit;
+ uint32_t donebit;
+ const unsigned long ioaddr; /* DMA controller regs addr */
+ const char *devname;
+ dma_irq_handler_t handler;
+ void *data;
+};
+
+
+#define __get_DMAC(IO,X) ({ *(volatile unsigned long *)((IO) + DMAC_##X##x); })
+
+#define __set_DMAC(IO,X,V) \
+do { \
+ *(volatile unsigned long *)((IO) + DMAC_##X##x) = (V); \
+ mb(); \
+} while(0)
+
+#define ___set_DMAC(IO,X,V) \
+do { \
+ *(volatile unsigned long *)((IO) + DMAC_##X##x) = (V); \
+} while(0)
+
+
+static struct frv_dma_channel frv_dma_channels[FRV_DMA_NCHANS] = {
+ [0] = {
+ .cap = FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK | FRV_DMA_CAP_DONE,
+ .irq = IRQ_CPU_DMA0,
+ .dreqbit = SIR_DREQ0_INPUT,
+ .dackbit = SOR_DACK0_OUTPUT,
+ .donebit = SOR_DONE0_OUTPUT,
+ .ioaddr = 0xfe000900,
+ },
+ [1] = {
+ .cap = FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK | FRV_DMA_CAP_DONE,
+ .irq = IRQ_CPU_DMA1,
+ .dreqbit = SIR_DREQ1_INPUT,
+ .dackbit = SOR_DACK1_OUTPUT,
+ .donebit = SOR_DONE1_OUTPUT,
+ .ioaddr = 0xfe000980,
+ },
+ [2] = {
+ .cap = FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK,
+ .irq = IRQ_CPU_DMA2,
+ .dreqbit = SIR_DREQ2_INPUT,
+ .dackbit = SOR_DACK2_OUTPUT,
+ .ioaddr = 0xfe000a00,
+ },
+ [3] = {
+ .cap = FRV_DMA_CAP_DREQ | FRV_DMA_CAP_DACK,
+ .irq = IRQ_CPU_DMA3,
+ .dreqbit = SIR_DREQ3_INPUT,
+ .dackbit = SOR_DACK3_OUTPUT,
+ .ioaddr = 0xfe000a80,
+ },
+ [4] = {
+ .cap = FRV_DMA_CAP_DREQ,
+ .irq = IRQ_CPU_DMA4,
+ .dreqbit = SIR_DREQ4_INPUT,
+ .ioaddr = 0xfe001000,
+ },
+ [5] = {
+ .cap = FRV_DMA_CAP_DREQ,
+ .irq = IRQ_CPU_DMA5,
+ .dreqbit = SIR_DREQ5_INPUT,
+ .ioaddr = 0xfe001080,
+ },
+ [6] = {
+ .cap = FRV_DMA_CAP_DREQ,
+ .irq = IRQ_CPU_DMA6,
+ .dreqbit = SIR_DREQ6_INPUT,
+ .ioaddr = 0xfe001100,
+ },
+ [7] = {
+ .cap = FRV_DMA_CAP_DREQ,
+ .irq = IRQ_CPU_DMA7,
+ .dreqbit = SIR_DREQ7_INPUT,
+ .ioaddr = 0xfe001180,
+ },
+};
+
+static DEFINE_RWLOCK(frv_dma_channels_lock);
+
+unsigned long frv_dma_inprogress;
+
+#define frv_clear_dma_inprogress(channel) \
+ atomic_clear_mask(1 << (channel), &frv_dma_inprogress);
+
+#define frv_set_dma_inprogress(channel) \
+ atomic_set_mask(1 << (channel), &frv_dma_inprogress);
+
+/*****************************************************************************/
+/*
+ * DMA irq handler - determine channel involved, grab status and call real handler
+ */
+static irqreturn_t dma_irq_handler(int irq, void *_channel, struct pt_regs *regs)
+{
+ struct frv_dma_channel *channel = _channel;
+
+ frv_clear_dma_inprogress(channel - frv_dma_channels);
+ return channel->handler(channel - frv_dma_channels,
+ __get_DMAC(channel->ioaddr, CSTR),
+ channel->data,
+ regs);
+
+} /* end dma_irq_handler() */
+
+/*****************************************************************************/
+/*
+ * Determine which DMA controllers are present on this CPU
+ */
+void __init frv_dma_init(void)
+{
+ unsigned long psr = __get_PSR();
+ int num_dma, i;
+
+ /* First, determine how many DMA channels are available */
+ switch (PSR_IMPLE(psr)) {
+ case PSR_IMPLE_FR405:
+ case PSR_IMPLE_FR451:
+ case PSR_IMPLE_FR501:
+ case PSR_IMPLE_FR551:
+ num_dma = FRV_DMA_8CHANS;
+ break;
+
+ case PSR_IMPLE_FR401:
+ default:
+ num_dma = FRV_DMA_4CHANS;
+ break;
+ }
+
+ /* Now mark all of the non-existent channels as reserved */
+ for(i = num_dma; i < FRV_DMA_NCHANS; i++)
+ frv_dma_channels[i].flags = FRV_DMA_FLAGS_RESERVED;
+
+} /* end frv_dma_init() */
+
+/*****************************************************************************/
+/*
+ * allocate a DMA controller channel and the IRQ associated with it
+ */
+int frv_dma_open(const char *devname,
+ unsigned long dmamask,
+ int dmacap,
+ dma_irq_handler_t handler,
+ unsigned long irq_flags,
+ void *data)
+{
+ struct frv_dma_channel *channel;
+ int dma, ret;
+ uint32_t val;
+
+ write_lock(&frv_dma_channels_lock);
+
+ ret = -ENOSPC;
+
+ for (dma = FRV_DMA_NCHANS - 1; dma >= 0; dma--) {
+ channel = &frv_dma_channels[dma];
+
+ if (!test_bit(dma, &dmamask))
+ continue;
+
+ if ((channel->cap & dmacap) != dmacap)
+ continue;
+
+ if (!frv_dma_channels[dma].flags)
+ goto found;
+ }
+
+ goto out;
+
+ found:
+ ret = request_irq(channel->irq, dma_irq_handler, irq_flags, devname, channel);
+ if (ret < 0)
+ goto out;
+
+ /* okay, we've allocated all the resources */
+ channel = &frv_dma_channels[dma];
+
+ channel->flags |= FRV_DMA_FLAGS_INUSE;
+ channel->devname = devname;
+ channel->handler = handler;
+ channel->data = data;
+
+ /* Now make sure we are set up for DMA and not GPIO */
+ /* SIR bit must be set for DMA to work */
+ __set_SIR(channel->dreqbit | __get_SIR());
+ /* SOR bits depend on what the caller requests */
+ val = __get_SOR();
+ if(dmacap & FRV_DMA_CAP_DACK)
+ val |= channel->dackbit;
+ else
+ val &= ~channel->dackbit;
+ if(dmacap & FRV_DMA_CAP_DONE)
+ val |= channel->donebit;
+ else
+ val &= ~channel->donebit;
+ __set_SOR(val);
+
+ ret = dma;
+ out:
+ write_unlock(&frv_dma_channels_lock);
+ return ret;
+} /* end frv_dma_open() */
+
+EXPORT_SYMBOL(frv_dma_open);
+
+/*****************************************************************************/
+/*
+ * close a DMA channel and its associated interrupt
+ */
+void frv_dma_close(int dma)
+{
+ struct frv_dma_channel *channel = &frv_dma_channels[dma];
+ unsigned long flags;
+
+ write_lock_irqsave(&frv_dma_channels_lock, flags);
+
+ free_irq(channel->irq, channel);
+ frv_dma_stop(dma);
+
+ channel->flags &= ~FRV_DMA_FLAGS_INUSE;
+
+ write_unlock_irqrestore(&frv_dma_channels_lock, flags);
+} /* end frv_dma_close() */
+
+EXPORT_SYMBOL(frv_dma_close);
+
+/*****************************************************************************/
+/*
+ * set static configuration on a DMA channel
+ */
+void frv_dma_config(int dma, unsigned long ccfr, unsigned long cctr, unsigned long apr)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+
+ ___set_DMAC(ioaddr, CCFR, ccfr);
+ ___set_DMAC(ioaddr, CCTR, cctr);
+ ___set_DMAC(ioaddr, APR, apr);
+ mb();
+
+} /* end frv_dma_config() */
+
+EXPORT_SYMBOL(frv_dma_config);
+
+/*****************************************************************************/
+/*
+ * start a DMA channel
+ */
+void frv_dma_start(int dma,
+ unsigned long sba, unsigned long dba,
+ unsigned long pix, unsigned long six, unsigned long bcl)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+
+ ___set_DMAC(ioaddr, SBA, sba);
+ ___set_DMAC(ioaddr, DBA, dba);
+ ___set_DMAC(ioaddr, PIX, pix);
+ ___set_DMAC(ioaddr, SIX, six);
+ ___set_DMAC(ioaddr, BCL, bcl);
+ ___set_DMAC(ioaddr, CSTR, 0);
+ mb();
+
+ __set_DMAC(ioaddr, CCTR, __get_DMAC(ioaddr, CCTR) | DMAC_CCTRx_ACT);
+ frv_set_dma_inprogress(dma);
+
+} /* end frv_dma_start() */
+
+EXPORT_SYMBOL(frv_dma_start);
+
+/*****************************************************************************/
+/*
+ * restart a DMA channel that's been stopped in circular addressing mode by comparison-end
+ */
+void frv_dma_restart_circular(int dma, unsigned long six)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+
+ ___set_DMAC(ioaddr, SIX, six);
+ ___set_DMAC(ioaddr, CSTR, __get_DMAC(ioaddr, CSTR) & ~DMAC_CSTRx_CE);
+ mb();
+
+ __set_DMAC(ioaddr, CCTR, __get_DMAC(ioaddr, CCTR) | DMAC_CCTRx_ACT);
+ frv_set_dma_inprogress(dma);
+
+} /* end frv_dma_restart_circular() */
+
+EXPORT_SYMBOL(frv_dma_restart_circular);
+
+/*****************************************************************************/
+/*
+ * stop a DMA channel
+ */
+void frv_dma_stop(int dma)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+ uint32_t cctr;
+
+ ___set_DMAC(ioaddr, CSTR, 0);
+ cctr = __get_DMAC(ioaddr, CCTR);
+ cctr &= ~(DMAC_CCTRx_IE | DMAC_CCTRx_ACT);
+ cctr |= DMAC_CCTRx_FC; /* fifo clear */
+ __set_DMAC(ioaddr, CCTR, cctr);
+ __set_DMAC(ioaddr, BCL, 0);
+ frv_clear_dma_inprogress(dma);
+} /* end frv_dma_stop() */
+
+EXPORT_SYMBOL(frv_dma_stop);
+
+/*****************************************************************************/
+/*
+ * test interrupt status of DMA channel
+ */
+int is_frv_dma_interrupting(int dma)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+
+ return __get_DMAC(ioaddr, CSTR) & (1 << 23);
+
+} /* end is_frv_dma_interrupting() */
+
+EXPORT_SYMBOL(is_frv_dma_interrupting);
+
+/*****************************************************************************/
+/*
+ * dump data about a DMA channel
+ */
+void frv_dma_dump(int dma)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+ unsigned long cstr, pix, six, bcl;
+
+ cstr = __get_DMAC(ioaddr, CSTR);
+ pix = __get_DMAC(ioaddr, PIX);
+ six = __get_DMAC(ioaddr, SIX);
+ bcl = __get_DMAC(ioaddr, BCL);
+
+ printk("DMA[%d] cstr=%lx pix=%lx six=%lx bcl=%lx\n", dma, cstr, pix, six, bcl);
+
+} /* end frv_dma_dump() */
+
+EXPORT_SYMBOL(frv_dma_dump);
+
+/*****************************************************************************/
+/*
+ * pause all DMA controllers
+ * - called by clock mangling routines
+ * - caller must be holding interrupts disabled
+ */
+void frv_dma_pause_all(void)
+{
+ struct frv_dma_channel *channel;
+ unsigned long ioaddr;
+ unsigned long cstr, cctr;
+ int dma;
+
+ write_lock(&frv_dma_channels_lock);
+
+ for (dma = FRV_DMA_NCHANS - 1; dma >= 0; dma--) {
+ channel = &frv_dma_channels[dma];
+
+ if (!(channel->flags & FRV_DMA_FLAGS_INUSE))
+ continue;
+
+ ioaddr = channel->ioaddr;
+ cctr = __get_DMAC(ioaddr, CCTR);
+ if (cctr & DMAC_CCTRx_ACT) {
+ cctr &= ~DMAC_CCTRx_ACT;
+ __set_DMAC(ioaddr, CCTR, cctr);
+
+ do {
+ cstr = __get_DMAC(ioaddr, CSTR);
+ } while (cstr & DMAC_CSTRx_BUSY);
+
+ if (cstr & DMAC_CSTRx_FED)
+ channel->flags |= FRV_DMA_FLAGS_PAUSED;
+ frv_clear_dma_inprogress(dma);
+ }
+ }
+
+} /* end frv_dma_pause_all() */
+
+EXPORT_SYMBOL(frv_dma_pause_all);
+
+/*****************************************************************************/
+/*
+ * resume paused DMA controllers
+ * - called by clock mangling routines
+ * - caller must be holding interrupts disabled
+ */
+void frv_dma_resume_all(void)
+{
+ struct frv_dma_channel *channel;
+ unsigned long ioaddr;
+ unsigned long cstr, cctr;
+ int dma;
+
+ for (dma = FRV_DMA_NCHANS - 1; dma >= 0; dma--) {
+ channel = &frv_dma_channels[dma];
+
+ if (!(channel->flags & FRV_DMA_FLAGS_PAUSED))
+ continue;
+
+ ioaddr = channel->ioaddr;
+ cstr = __get_DMAC(ioaddr, CSTR);
+ cstr &= ~(DMAC_CSTRx_FED | DMAC_CSTRx_INT);
+ __set_DMAC(ioaddr, CSTR, cstr);
+
+ cctr = __get_DMAC(ioaddr, CCTR);
+ cctr |= DMAC_CCTRx_ACT;
+ __set_DMAC(ioaddr, CCTR, cctr);
+
+ channel->flags &= ~FRV_DMA_FLAGS_PAUSED;
+ frv_set_dma_inprogress(dma);
+ }
+
+ write_unlock(&frv_dma_channels_lock);
+
+} /* end frv_dma_resume_all() */
+
+EXPORT_SYMBOL(frv_dma_resume_all);
+
+/*****************************************************************************/
+/*
+ * dma status clear
+ */
+void frv_dma_status_clear(int dma)
+{
+ unsigned long ioaddr = frv_dma_channels[dma].ioaddr;
+ uint32_t cctr;
+ ___set_DMAC(ioaddr, CSTR, 0);
+
+ cctr = __get_DMAC(ioaddr, CCTR);
+} /* end frv_dma_status_clear() */
+
+EXPORT_SYMBOL(frv_dma_status_clear);