+/*
+ * Return the address of the command within a descriptor.
+ */
+static unsigned int mxs_dma_cmd_address(struct mxs_dma_desc *desc)
+{
+ return desc->address + offsetof(struct mxs_dma_desc, cmd);
+}
+
+/*
+ * Read a DMA channel's hardware semaphore.
+ *
+ * As used by the MXS platform's DMA software, the DMA channel's hardware
+ * semaphore reflects the number of DMA commands the hardware will process, but
+ * has not yet finished. This is a volatile value read directly from hardware,
+ * so it must be be viewed as immediately stale.
+ *
+ * If the channel is not marked busy, or has finished processing all its
+ * commands, this value should be zero.
+ *
+ * See mxs_dma_append() for details on how DMA command blocks must be configured
+ * to maintain the expected behavior of the semaphore's value.
+ */
+static int mxs_dma_read_semaphore(int channel)
+{
+ struct mxs_apbh_regs *apbh_regs =
+ (struct mxs_apbh_regs *)MXS_APBH_BASE;
+ uint32_t tmp;
+ int ret;
+
+ ret = mxs_dma_validate_chan(channel);
+ if (ret)
+ return ret;
+
+ tmp = readl(&apbh_regs->ch[channel].hw_apbh_ch_sema);
+
+ tmp &= APBH_CHn_SEMA_PHORE_MASK;
+ tmp >>= APBH_CHn_SEMA_PHORE_OFFSET;
+
+ return tmp;
+}
+
+#ifndef CONFIG_SYS_DCACHE_OFF
+void mxs_dma_flush_desc(struct mxs_dma_desc *desc)
+{
+ uint32_t addr;
+ uint32_t size;
+
+ addr = (uint32_t)desc;
+ size = roundup(sizeof(struct mxs_dma_desc), MXS_DMA_ALIGNMENT);
+
+ flush_dcache_range(addr, addr + size);
+}
+#else
+inline void mxs_dma_flush_desc(struct mxs_dma_desc *desc) {}
+#endif
+