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-rw-r--r--arch/blackfin/kernel/bfin_dma_5xx.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/arch/blackfin/kernel/bfin_dma_5xx.c b/arch/blackfin/kernel/bfin_dma_5xx.c
index 8531693..763ed84 100644
--- a/arch/blackfin/kernel/bfin_dma_5xx.c
+++ b/arch/blackfin/kernel/bfin_dma_5xx.c
@@ -20,6 +20,11 @@
#include <asm/dma.h>
#include <asm/uaccess.h>
+/*
+ * To make sure we work around 05000119 - we always check DMA_DONE bit,
+ * never the DMA_RUN bit
+ */
+
struct dma_channel dma_ch[MAX_DMA_CHANNELS];
EXPORT_SYMBOL(dma_ch);
@@ -232,6 +237,87 @@ void blackfin_dma_resume(void)
void __init blackfin_dma_early_init(void)
{
bfin_write_MDMA_S0_CONFIG(0);
+ bfin_write_MDMA_S1_CONFIG(0);
+}
+
+void __init early_dma_memcpy(void *pdst, const void *psrc, size_t size)
+{
+ unsigned long dst = (unsigned long)pdst;
+ unsigned long src = (unsigned long)psrc;
+ struct dma_register *dst_ch, *src_ch;
+
+ /* We assume that everything is 4 byte aligned, so include
+ * a basic sanity check
+ */
+ BUG_ON(dst % 4);
+ BUG_ON(src % 4);
+ BUG_ON(size % 4);
+
+ /* Force a sync in case a previous config reset on this channel
+ * occurred. This is needed so subsequent writes to DMA registers
+ * are not spuriously lost/corrupted.
+ */
+ __builtin_bfin_ssync();
+
+ src_ch = 0;
+ /* Find an avalible memDMA channel */
+ while (1) {
+ if (!src_ch || src_ch == (struct dma_register *)MDMA_S1_NEXT_DESC_PTR) {
+ dst_ch = (struct dma_register *)MDMA_D0_NEXT_DESC_PTR;
+ src_ch = (struct dma_register *)MDMA_S0_NEXT_DESC_PTR;
+ } else {
+ dst_ch = (struct dma_register *)MDMA_D1_NEXT_DESC_PTR;
+ src_ch = (struct dma_register *)MDMA_S1_NEXT_DESC_PTR;
+ }
+
+ if (!bfin_read16(&src_ch->cfg)) {
+ break;
+ } else {
+ if (bfin_read16(&src_ch->irq_status) & DMA_DONE)
+ bfin_write16(&src_ch->cfg, 0);
+ }
+
+ }
+
+ /* Destination */
+ bfin_write32(&dst_ch->start_addr, dst);
+ bfin_write16(&dst_ch->x_count, size >> 2);
+ bfin_write16(&dst_ch->x_modify, 1 << 2);
+ bfin_write16(&dst_ch->irq_status, DMA_DONE | DMA_ERR);
+
+ /* Source */
+ bfin_write32(&src_ch->start_addr, src);
+ bfin_write16(&src_ch->x_count, size >> 2);
+ bfin_write16(&src_ch->x_modify, 1 << 2);
+ bfin_write16(&src_ch->irq_status, DMA_DONE | DMA_ERR);
+
+ /* Enable */
+ bfin_write16(&src_ch->cfg, DMAEN | WDSIZE_32);
+ bfin_write16(&dst_ch->cfg, WNR | DI_EN | DMAEN | WDSIZE_32);
+
+ /* Since we are atomic now, don't use the workaround ssync */
+ __builtin_bfin_ssync();
+}
+
+void __init early_dma_memcpy_done(void)
+{
+ while ((bfin_read_MDMA_S0_CONFIG() && !(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE)) ||
+ (bfin_read_MDMA_S1_CONFIG() && !(bfin_read_MDMA_D1_IRQ_STATUS() & DMA_DONE)))
+ continue;
+
+ bfin_write_MDMA_D0_IRQ_STATUS(DMA_DONE | DMA_ERR);
+ bfin_write_MDMA_D1_IRQ_STATUS(DMA_DONE | DMA_ERR);
+ /*
+ * Now that DMA is done, we would normally flush cache, but
+ * i/d cache isn't running this early, so we don't bother,
+ * and just clear out the DMA channel for next time
+ */
+ bfin_write_MDMA_S0_CONFIG(0);
+ bfin_write_MDMA_S1_CONFIG(0);
+ bfin_write_MDMA_D0_CONFIG(0);
+ bfin_write_MDMA_D1_CONFIG(0);
+
+ __builtin_bfin_ssync();
}
/**
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