spi: dw-spi: Convert 16bit accesses to 32bit accesses
Altera's Arria10 SoC interconnect requires a 32-bit write for APB
peripherals. The current spi-dw driver uses 16-bit accesses in
some locations. This patch converts all the 16-bit reads and
writes to 32-bit reads and writes.
Additional Documentation to Support this Change:
The DW_apb_ssi databook states:
"All registers in the DW_apb_ssi are addressed at 32-bit boundaries
to remain consistent with the AHB bus. Where the physical size of
any register is less than 32-bits wide, the upper unused bits of
the 32-bit boundary are reserved. Writing to these bits has no
effect; reading from these bits returns 0." [1]
[1] Section 6.1 of dw_apb_ssi.pdf (version 3.22a)
Request for test with platforms using the DesignWare SPI IP.
Tested On:
Altera CycloneV development kit
Altera Arria10 development kit
Compile tested for build errors on x86_64 (allyesconfigs)
Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Reviewed-and-tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
index 0f01069..cafac22 100644
--- a/drivers/spi/spi-dw.c
+++ b/drivers/spi/spi-dw.c
@@ -157,7 +157,7 @@
u32 tx_left, tx_room, rxtx_gap;
tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
- tx_room = dws->fifo_len - dw_readw(dws, DW_SPI_TXFLR);
+ tx_room = dws->fifo_len - dw_readl(dws, DW_SPI_TXFLR);
/*
* Another concern is about the tx/rx mismatch, we
@@ -178,7 +178,7 @@
{
u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
- return min_t(u32, rx_left, dw_readw(dws, DW_SPI_RXFLR));
+ return min_t(u32, rx_left, dw_readl(dws, DW_SPI_RXFLR));
}
static void dw_writer(struct dw_spi *dws)
@@ -194,7 +194,7 @@
else
txw = *(u16 *)(dws->tx);
}
- dw_writew(dws, DW_SPI_DR, txw);
+ dw_writel(dws, DW_SPI_DR, txw);
dws->tx += dws->n_bytes;
}
}
@@ -205,7 +205,7 @@
u16 rxw;
while (max--) {
- rxw = dw_readw(dws, DW_SPI_DR);
+ rxw = dw_readl(dws, DW_SPI_DR);
/* Care rx only if the transfer's original "rx" is not null */
if (dws->rx_end - dws->len) {
if (dws->n_bytes == 1)
@@ -228,11 +228,11 @@
static irqreturn_t interrupt_transfer(struct dw_spi *dws)
{
- u16 irq_status = dw_readw(dws, DW_SPI_ISR);
+ u16 irq_status = dw_readl(dws, DW_SPI_ISR);
/* Error handling */
if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
- dw_readw(dws, DW_SPI_ICR);
+ dw_readl(dws, DW_SPI_ICR);
int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
return IRQ_HANDLED;
}
@@ -257,7 +257,7 @@
{
struct spi_master *master = dev_id;
struct dw_spi *dws = spi_master_get_devdata(master);
- u16 irq_status = dw_readw(dws, DW_SPI_ISR) & 0x3f;
+ u16 irq_status = dw_readl(dws, DW_SPI_ISR) & 0x3f;
if (!irq_status)
return IRQ_NONE;
@@ -354,7 +354,7 @@
cr0 |= (chip->tmode << SPI_TMOD_OFFSET);
}
- dw_writew(dws, DW_SPI_CTRL0, cr0);
+ dw_writel(dws, DW_SPI_CTRL0, cr0);
/* Check if current transfer is a DMA transaction */
if (master->can_dma && master->can_dma(master, spi, transfer))
@@ -375,7 +375,7 @@
}
} else if (!chip->poll_mode) {
txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes);
- dw_writew(dws, DW_SPI_TXFLTR, txlevel);
+ dw_writel(dws, DW_SPI_TXFLTR, txlevel);
/* Set the interrupt mask */
imask |= SPI_INT_TXEI | SPI_INT_TXOI |
@@ -499,11 +499,11 @@
u32 fifo;
for (fifo = 1; fifo < 256; fifo++) {
- dw_writew(dws, DW_SPI_TXFLTR, fifo);
- if (fifo != dw_readw(dws, DW_SPI_TXFLTR))
+ dw_writel(dws, DW_SPI_TXFLTR, fifo);
+ if (fifo != dw_readl(dws, DW_SPI_TXFLTR))
break;
}
- dw_writew(dws, DW_SPI_TXFLTR, 0);
+ dw_writel(dws, DW_SPI_TXFLTR, 0);
dws->fifo_len = (fifo == 1) ? 0 : fifo;
dev_dbg(dev, "Detected FIFO size: %u bytes\n", dws->fifo_len);