spi: dw: Move Non-DMA code to the DW PCIe-SPI driver

This is a preparation patch before adding the DW DMA support into the
DW SPI MMIO driver. We need to unpin the Non-DMA-specific code from the
intended to be generic DW APB SSI DMA code. This isn't that hard,
since the most part of the spi-dw-mid.c driver in fact implements a
generic DMA interface for the DW SPI controller driver. The only Intel
MID specifics concern getting the max frequency from the MRST Clock
Control Unit and fetching the DMA controller channels from
corresponding PCIe DMA controller. Since first one is related with the
SPI interface configuration we moved it' implementation into the
DW PCIe-SPI driver module. After that former spi-dw-mid.c file
can be just renamed to be the DW SPI DMA module optionally compiled in to
the DW APB SSI core driver.

Co-developed-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Co-developed-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Georgy Vlasov <Georgy.Vlasov@baikalelectronics.ru>
Signed-off-by: Ramil Zaripov <Ramil.Zaripov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: devicetree@vger.kernel.org
Link: https://lore.kernel.org/r/20200529131205.31838-11-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 47 insertions, 3 deletions

diff --git a/drivers/spi/spi-dw-pci.c b/drivers/spi/spi-dw-pci.c
index dde54a918b5d..c13707b8493e 100644
--- a/drivers/spi/spi-dw-pci.c
+++ b/drivers/spi/spi-dw-pci.c
@@ -15,6 +15,15 @@
 
 #define DRIVER_NAME "dw_spi_pci"
 
+/* HW info for MRST Clk Control Unit, 32b reg per controller */
+#define MRST_SPI_CLK_BASE	100000000	/* 100m */
+#define MRST_CLK_SPI_REG	0xff11d86c
+#define CLK_SPI_BDIV_OFFSET	0
+#define CLK_SPI_BDIV_MASK	0x00000007
+#define CLK_SPI_CDIV_OFFSET	9
+#define CLK_SPI_CDIV_MASK	0x00000e00
+#define CLK_SPI_DISABLE_OFFSET	8
+
 struct spi_pci_desc {
 	int	(*setup)(struct dw_spi *);
 	u16	num_cs;
@@ -22,20 +31,55 @@ struct spi_pci_desc {
 	u32	max_freq;
 };
 
+static int spi_mid_init(struct dw_spi *dws)
+{
+	void __iomem *clk_reg;
+	u32 clk_cdiv;
+
+	clk_reg = ioremap(MRST_CLK_SPI_REG, 16);
+	if (!clk_reg)
+		return -ENOMEM;
+
+	/* Get SPI controller operating freq info */
+	clk_cdiv = readl(clk_reg + dws->bus_num * sizeof(u32));
+	clk_cdiv &= CLK_SPI_CDIV_MASK;
+	clk_cdiv >>= CLK_SPI_CDIV_OFFSET;
+	dws->max_freq = MRST_SPI_CLK_BASE / (clk_cdiv + 1);
+
+	iounmap(clk_reg);
+
+	/* Register hook to configure CTRLR0 */
+	dws->update_cr0 = dw_spi_update_cr0;
+
+	dw_spi_mid_setup_dma_mfld(dws);
+
+	return 0;
+}
+
+static int spi_generic_init(struct dw_spi *dws)
+{
+	/* Register hook to configure CTRLR0 */
+	dws->update_cr0 = dw_spi_update_cr0;
+
+	dw_spi_mid_setup_dma_generic(dws);
+
+	return 0;
+}
+
 static struct spi_pci_desc spi_pci_mid_desc_1 = {
-	.setup = dw_spi_mid_init_mfld,
+	.setup = spi_mid_init,
 	.num_cs = 5,
 	.bus_num = 0,
 };
 
 static struct spi_pci_desc spi_pci_mid_desc_2 = {
-	.setup = dw_spi_mid_init_mfld,
+	.setup = spi_mid_init,
 	.num_cs = 2,
 	.bus_num = 1,
 };
 
 static struct spi_pci_desc spi_pci_ehl_desc = {
-	.setup = dw_spi_mid_init_generic,
+	.setup = spi_generic_init,
 	.num_cs = 2,
 	.bus_num = -1,
 	.max_freq = 100000000,