#include "gsc3280mac1000.h"
#include "gsc3280mac_dma.h"

static int gsc3280mac1000_dma_init(void __iomem *ioaddr, int pbl, u32 dma_tx,
			      u32 dma_rx)
{
	u32 value = readl(ioaddr + DMA_BUS_MODE);
	int limit;

	/* DMA SW reset */
	value |= DMA_BUS_MODE_SFT_RESET;
	writel(value, ioaddr + DMA_BUS_MODE);
	limit = 15000;
	while (limit--) {
		if (!(readl(ioaddr + DMA_BUS_MODE) & DMA_BUS_MODE_SFT_RESET))
			break;
	}
	if (limit < 0)
		return -EBUSY;

	//value =  /*DMA_BUS_MODE_FB |*/  DMA_BUS_MODE_4PBL |
	value =  DMA_BUS_MODE_FB |  DMA_BUS_MODE_4PBL |
	    ((pbl << DMA_BUS_MODE_PBL_SHIFT) |
	     (pbl << DMA_BUS_MODE_RPBL_SHIFT));


#ifdef CONFIG_GSC3280MAC_DA
	value |= DMA_BUS_MODE_DA;	/* Rx has priority over tx */
#endif
	writel(value, ioaddr + DMA_BUS_MODE);

	/* Mask interrupts by writing to CSR7 */
	writel(DMA_INTR_DEFAULT_MASK, ioaddr + DMA_INTR_ENA);

	/* The base address of the RX/TX descriptor lists must be written into
	 * DMA CSR3 and CSR4, respectively. */
	writel(dma_tx, ioaddr + DMA_TX_BASE_ADDR);
	writel(dma_rx, ioaddr + DMA_RCV_BASE_ADDR);

	return 0;
}

static void gsc3280mac1000_dma_operation_mode(void __iomem *ioaddr, int txmode,
				    int rxmode)
{
	u32 csr6 = readl(ioaddr + DMA_CONTROL);

	if (txmode == SF_DMA_MODE) {
		CHIP_DBG(KERN_DEBUG "GMAC: enable TX store and forward mode\n");
		/* Transmit COE type 2 cannot be done in cut-through mode. */
		csr6 |= DMA_CONTROL_TSF;
		/* Operating on second frame increase the performance
		 * especially when transmit store-and-forward is used.*/
		csr6 |= DMA_CONTROL_OSF;
	} else {
		CHIP_DBG(KERN_DEBUG "GMAC: disabling TX store and forward mode"
			      " (threshold = %d)\n", txmode);
		csr6 &= ~DMA_CONTROL_TSF;
		csr6 &= DMA_CONTROL_TC_TX_MASK;
		/* Set the transmit threshold */
		if (txmode <= 32)
			csr6 |= DMA_CONTROL_TTC_32;
		else if (txmode <= 64)
			csr6 |= DMA_CONTROL_TTC_64;
		else if (txmode <= 128)
			csr6 |= DMA_CONTROL_TTC_128;
		else if (txmode <= 192)
			csr6 |= DMA_CONTROL_TTC_192;
		else
			csr6 |= DMA_CONTROL_TTC_256;
	}

	if (rxmode == SF_DMA_MODE) {
		CHIP_DBG(KERN_DEBUG "GMAC: enable RX store and forward mode\n");
		csr6 |= DMA_CONTROL_RSF;
//		csr6 |= DMA_CONTROL_DT; //NOTE: set 1 to report IP/TCP/UDP/ICMP checksum error frame to CPU, set 0 to drop the frame silently. 
	} else {
		CHIP_DBG(KERN_DEBUG "GMAC: disabling RX store and forward mode"
			      " (threshold = %d)\n", rxmode);
		csr6 &= ~DMA_CONTROL_RSF;
		csr6 &= DMA_CONTROL_TC_RX_MASK;
		if (rxmode <= 32)
			csr6 |= DMA_CONTROL_RTC_32;
		else if (rxmode <= 64)
			csr6 |= DMA_CONTROL_RTC_64;
		else if (rxmode <= 96)
			csr6 |= DMA_CONTROL_RTC_96;
		else
			csr6 |= DMA_CONTROL_RTC_128;
	}

	writel(csr6, ioaddr + DMA_CONTROL);
}

/* Not yet implemented --- no RMON module */
static void gsc3280mac1000_dma_diagnostic_fr(void *data,
		  struct gsc3280mac_extra_stats *x, void __iomem *ioaddr)
{
	return;
}

static void gsc3280mac1000_dump_dma_regs(void __iomem *ioaddr)
{
	int i;
	pr_info(" DMA registers\n");
	for (i = 0; i < 22; i++) {
		if ((i < 9) || (i > 17)) {
			int offset = i * 4;
			pr_err("\t Reg No. %d (offset 0x%x): 0x%08x\n", i,
			       (DMA_BUS_MODE + offset),
			       readl(ioaddr + DMA_BUS_MODE + offset));
		}
	}
}

const struct gsc3280mac_dma_ops gsc3280mac1000_dma_ops = {
	.init = gsc3280mac1000_dma_init,
	.dump_regs = gsc3280mac1000_dump_dma_regs,
	.dma_mode = gsc3280mac1000_dma_operation_mode,
	.dma_diagnostic_fr = gsc3280mac1000_dma_diagnostic_fr,
	.enable_dma_transmission = gsc3280mac_enable_dma_transmission,
	.enable_dma_irq = gsc3280mac_enable_dma_irq,
	.disable_dma_irq = gsc3280mac_disable_dma_irq,
	.start_tx = gsc3280mac_dma_start_tx,
	.stop_tx = gsc3280mac_dma_stop_tx,
	.start_rx = gsc3280mac_dma_start_rx,
	.stop_rx = gsc3280mac_dma_stop_rx,
	.dma_interrupt = gsc3280mac_dma_interrupt,
};