/**
* mpc52xx_lpbfifo_kick - Trigger the next block of data to be transferred
*/
static void mpc52xx_lpbfifo_kick(struct mpc52xx_lpbfifo_request *req)
{
size_t transfer_size = req->size - req->pos;
struct bcom_bd *bd;
void __iomem *reg;
u32 *data;
int i;
int bit_fields;
int dma = !(req->flags & MPC52XX_LPBFIFO_FLAG_NO_DMA);
int write = req->flags & MPC52XX_LPBFIFO_FLAG_WRITE;
int poll_dma = req->flags & MPC52XX_LPBFIFO_FLAG_POLL_DMA;
/* Set and clear the reset bits; is good practice in User Manual */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);
/* set master enable bit */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000001);
if (!dma) {
/* While the FIFO can be setup for transfer sizes as large as
* 16M-1, the FIFO itself is only 512 bytes deep and it does
* not generate interrupts for FIFO full events (only transfer
* complete will raise an IRQ). Therefore when not using
* Bestcomm to drive the FIFO it needs to either be polled, or
* transfers need to constrained to the size of the fifo.
*
* This driver restricts the size of the transfer
*/
if (transfer_size > 512)
transfer_size = 512;
/* Load the FIFO with data */
if (write) {
reg = lpbfifo.regs + LPBFIFO_REG_FIFO_DATA;
data = req->data + req->pos;
for (i = 0; i < transfer_size; i += 4)
out_be32(reg, *data++);
}
/* Unmask both error and completion irqs */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000301);
} else {
/* Choose the correct direction
*
* Configure the watermarks so DMA will always complete correctly.
* It may be worth experimenting with the ALARM value to see if
* there is a performance impacit. However, if it is wrong there
* is a risk of DMA not transferring the last chunk of data
*/
if (write) {
out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1e4);
out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 7);
lpbfifo.bcom_cur_task = lpbfifo.bcom_tx_task;
} else {
out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1ff);
out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 0);
lpbfifo.bcom_cur_task = lpbfifo.bcom_rx_task;
if (poll_dma) {
if (lpbfifo.dma_irqs_enabled) {
disable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
lpbfifo.dma_irqs_enabled = 0;
}
} else {
if (!lpbfifo.dma_irqs_enabled) {
enable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
lpbfifo.dma_irqs_enabled = 1;
}
}
}
bd = bcom_prepare_next_buffer(lpbfifo.bcom_cur_task);
bd->status = transfer_size;
if (!write) {
/*
* In the DMA read case, the DMA doesn't complete,
* possibly due to incorrect watermarks in the ALARM
* and CONTROL regs. For now instead of trying to
* determine the right watermarks that will make this
* work, just increase the number of bytes the FIFO is
* expecting.
*
* When submitting another operation, the FIFO will get
* reset, so the condition of the FIFO waiting for a
* non-existent 4 bytes will get cleared.
*/
transfer_size += 4; /* BLECH! */
}
bd->data[0] = req->data_phys + req->pos;
bcom_submit_next_buffer(lpbfifo.bcom_cur_task, NULL);
/* error irq & master enabled bit */
bit_fields = 0x00000201;
/* Unmask irqs */
if (write && (!poll_dma))
bit_fields |= 0x00000100; /* completion irq too */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, bit_fields);
}
/* Set transfer size, width, chip select and READ mode */
out_be32(lpbfifo.regs + LPBFIFO_REG_START_ADDRESS,
req->offset + req->pos);
out_be32(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, transfer_size);
bit_fields = req->cs << 24 | 0x000008;
if (!write)
bit_fields |= 0x010000; /* read mode */
out_be32(lpbfifo.regs + LPBFIFO_REG_CONTROL, bit_fields);
/* Kick it off */
out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
if (dma)
bcom_enable(lpbfifo.bcom_cur_task);
}
static void mpc52xx_lpbfifo_kick(struct mpc52xx_lpbfifo_request *req)
{
size_t transfer_size = req->size - req->pos;
struct bcom_bd *bd;
void __iomem *reg;
u32 *data;
int i;
int bit_fields;
int dma = !(req->flags & MPC52XX_LPBFIFO_FLAG_NO_DMA);
int write = req->flags & MPC52XX_LPBFIFO_FLAG_WRITE;
int poll_dma = req->flags & MPC52XX_LPBFIFO_FLAG_POLL_DMA;
/* */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x01010000);
/* */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000001);
if (!dma) {
/*
*/
if (transfer_size > 512)
transfer_size = 512;
/* */
if (write) {
reg = lpbfifo.regs + LPBFIFO_REG_FIFO_DATA;
data = req->data + req->pos;
for (i = 0; i < transfer_size; i += 4)
out_be32(reg, *data++);
}
/* */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, 0x00000301);
} else {
/*
*/
if (write) {
out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1e4);
out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 7);
lpbfifo.bcom_cur_task = lpbfifo.bcom_tx_task;
} else {
out_be32(lpbfifo.regs + LPBFIFO_REG_FIFO_ALARM, 0x1ff);
out_8(lpbfifo.regs + LPBFIFO_REG_FIFO_CONTROL, 0);
lpbfifo.bcom_cur_task = lpbfifo.bcom_rx_task;
if (poll_dma) {
if (lpbfifo.dma_irqs_enabled) {
disable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
lpbfifo.dma_irqs_enabled = 0;
}
} else {
if (!lpbfifo.dma_irqs_enabled) {
enable_irq(bcom_get_task_irq(lpbfifo.bcom_rx_task));
lpbfifo.dma_irqs_enabled = 1;
}
}
}
bd = bcom_prepare_next_buffer(lpbfifo.bcom_cur_task);
bd->status = transfer_size;
if (!write) {
/*
*/
transfer_size += 4; /* */
}
bd->data[0] = req->data_phys + req->pos;
bcom_submit_next_buffer(lpbfifo.bcom_cur_task, NULL);
/* */
bit_fields = 0x00000201;
/* */
if (write && (!poll_dma))
bit_fields |= 0x00000100; /* */
out_be32(lpbfifo.regs + LPBFIFO_REG_ENABLE, bit_fields);
}
/* */
out_be32(lpbfifo.regs + LPBFIFO_REG_START_ADDRESS,
req->offset + req->pos);
out_be32(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, transfer_size);
bit_fields = req->cs << 24 | 0x000008;
if (!write)
bit_fields |= 0x010000; /* */
out_be32(lpbfifo.regs + LPBFIFO_REG_CONTROL, bit_fields);
/* */
out_8(lpbfifo.regs + LPBFIFO_REG_PACKET_SIZE, 0x01);
if (dma)
bcom_enable(lpbfifo.bcom_cur_task);
}
