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Diffstat (limited to 'src/soc/nvidia/tegra210/dma.c')
-rw-r--r--src/soc/nvidia/tegra210/dma.c147
1 files changed, 147 insertions, 0 deletions
diff --git a/src/soc/nvidia/tegra210/dma.c b/src/soc/nvidia/tegra210/dma.c
new file mode 100644
index 0000000000..9f04e9777f
--- /dev/null
+++ b/src/soc/nvidia/tegra210/dma.c
@@ -0,0 +1,147 @@
+/*
+ * (C) Copyright 2010,2011
+ * NVIDIA Corporation <www.nvidia.com>
+ * Copyright 2014 Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <arch/io.h>
+#include <console/console.h>
+#include <inttypes.h>
+#include <soc/addressmap.h>
+#include <soc/dma.h>
+#include <stddef.h>
+#include <stdlib.h>
+
+struct apb_dma * const apb_dma = (struct apb_dma *)TEGRA_APB_DMA_BASE;
+
+#define APB_DMA_OFFSET(n) \
+ (struct apb_dma_channel_regs *)(TEGRA_APB_DMA_BASE + n)
+struct apb_dma_channel apb_dma_channels[] = {
+ { .num = 0, .regs = APB_DMA_OFFSET(0x1000) },
+ { .num = 1, .regs = APB_DMA_OFFSET(0x1040) },
+ { .num = 2, .regs = APB_DMA_OFFSET(0x1080) },
+ { .num = 3, .regs = APB_DMA_OFFSET(0x10c0) },
+ { .num = 4, .regs = APB_DMA_OFFSET(0x1100) },
+ { .num = 5, .regs = APB_DMA_OFFSET(0x1140) },
+ { .num = 6, .regs = APB_DMA_OFFSET(0x1180) },
+ { .num = 7, .regs = APB_DMA_OFFSET(0x11c0) },
+ { .num = 8, .regs = APB_DMA_OFFSET(0x1200) },
+ { .num = 9, .regs = APB_DMA_OFFSET(0x1240) },
+ { .num = 10, .regs = APB_DMA_OFFSET(0x1280) },
+ { .num = 11, .regs = APB_DMA_OFFSET(0x12c0) },
+ { .num = 12, .regs = APB_DMA_OFFSET(0x1300) },
+ { .num = 13, .regs = APB_DMA_OFFSET(0x1340) },
+ { .num = 14, .regs = APB_DMA_OFFSET(0x1380) },
+ { .num = 15, .regs = APB_DMA_OFFSET(0x13c0) },
+ { .num = 16, .regs = APB_DMA_OFFSET(0x1400) },
+ { .num = 17, .regs = APB_DMA_OFFSET(0x1440) },
+ { .num = 18, .regs = APB_DMA_OFFSET(0x1480) },
+ { .num = 19, .regs = APB_DMA_OFFSET(0x14c0) },
+ { .num = 20, .regs = APB_DMA_OFFSET(0x1500) },
+ { .num = 21, .regs = APB_DMA_OFFSET(0x1540) },
+ { .num = 22, .regs = APB_DMA_OFFSET(0x1580) },
+ { .num = 23, .regs = APB_DMA_OFFSET(0x15c0) },
+ { .num = 24, .regs = APB_DMA_OFFSET(0x1600) },
+ { .num = 25, .regs = APB_DMA_OFFSET(0x1640) },
+ { .num = 26, .regs = APB_DMA_OFFSET(0x1680) },
+ { .num = 27, .regs = APB_DMA_OFFSET(0x16c0) },
+ { .num = 28, .regs = APB_DMA_OFFSET(0x1700) },
+ { .num = 29, .regs = APB_DMA_OFFSET(0x1740) },
+ { .num = 30, .regs = APB_DMA_OFFSET(0x1780) },
+ { .num = 31, .regs = APB_DMA_OFFSET(0x17c0) },
+};
+
+int dma_busy(struct apb_dma_channel * const channel)
+{
+ /*
+ * In continuous mode, the BSY_n bit in APB_DMA_STATUS and
+ * BSY in APBDMACHAN_CHANNEL_n_STA_0 will remain set as '1' so long
+ * as the channel is enabled. So for this function we'll use the
+ * DMA_ACTIVITY bit.
+ */
+ return read32(&channel->regs->sta) & APB_STA_DMA_ACTIVITY ? 1 : 0;
+}
+/* claim a DMA channel */
+struct apb_dma_channel * const dma_claim(void)
+{
+ int i;
+ struct apb_dma_channel_regs *regs = NULL;
+
+ /*
+ * Set global enable bit, otherwise register access to channel
+ * DMA registers will not be possible.
+ */
+ setbits_le32(&apb_dma->command, APB_COMMAND_GEN);
+
+ for (i = 0; i < ARRAY_SIZE(apb_dma_channels); i++) {
+ regs = apb_dma_channels[i].regs;
+
+ if (!apb_dma_channels[i].in_use) {
+ u32 status = read32(&regs->sta);
+ if (status & (1 << i)) {
+ /* FIXME: should this be fatal? */
+ printk(BIOS_DEBUG, "%s: DMA channel %d busy?\n",
+ __func__, i);
+ }
+ break;
+ }
+ }
+
+ if (i == ARRAY_SIZE(apb_dma_channels))
+ return NULL;
+
+ apb_dma_channels[i].in_use = 1;
+ return &apb_dma_channels[i];
+}
+
+/* release a DMA channel */
+void dma_release(struct apb_dma_channel * const channel)
+{
+ int i;
+
+ /* FIXME: make this "thread" friendly */
+ while (dma_busy(channel))
+ ;
+
+ channel->in_use = 0;
+
+ /* clear the global enable bit if no channels are in use */
+ for (i = 0; i < ARRAY_SIZE(apb_dma_channels); i++) {
+ if (apb_dma_channels[i].in_use)
+ return;
+ }
+
+ clrbits_le32(&apb_dma->command, APB_COMMAND_GEN);
+}
+
+int dma_start(struct apb_dma_channel * const channel)
+{
+ struct apb_dma_channel_regs *regs = channel->regs;
+
+ /* Set ENB bit for this channel */
+ setbits_le32(&regs->csr, APB_CSR_ENB);
+
+ return 0;
+}
+
+int dma_stop(struct apb_dma_channel * const channel)
+{
+ struct apb_dma_channel_regs *regs = channel->regs;
+
+ /* Clear ENB bit for this channel */
+ clrbits_le32(&regs->csr, APB_CSR_ENB);
+
+ return 0;
+}