[PATCH v5 19/33] spi: dw: Add device tree properties for fields in CTRL1

Sean Anderson
2020-03-04T15:01:23Z

On 3/4/20 1:15 AM, Rick Chen wrote:
> Hi Sean
>
>> Some devices have different layouts for the fields in CTRL1 (e.g. the
>
> Still not fix this typo in commit message
> CTRL1 -> CTRL0
>
> Thanks,
> Rick

Ah, whoops. I think I fixed it, the forgot I had done so, and changed it
again. Hopefully I can get this straight.

--Sean

>
>> Kendryte K210). Allow this layout to be configurable from the device tree.
>> The documentation has been taken from Linux.
>>
>> Signed-off-by: Sean Anderson <seanga2@gmail.com>
>> Reviewed-by: Simon Glass <sjg@chromium.org>
>> ---
>>
>> Changes in v4:
>> - New
>>
>> .../spi/snps,dw-apb-ssi.txt | 43 +++++++++++++++++++
>> drivers/spi/designware_spi.c | 40 ++++++++++-------
>> 2 files changed, 68 insertions(+), 15 deletions(-)
>> create mode 100644 doc/device-tree-bindings/spi/snps,dw-apb-ssi.txt
>>
>> diff --git a/doc/device-tree-bindings/spi/snps,dw-apb-ssi.txt b/doc/device-tree-bindings/spi/snps,dw-apb-ssi.txt
>> new file mode 100644
>> index 0000000000..4b6152f6b7
>> --- /dev/null
>> +++ b/doc/device-tree-bindings/spi/snps,dw-apb-ssi.txt
>> @@ -0,0 +1,43 @@
>> +Synopsys DesignWare AMBA 2.0 Synchronous Serial Interface.
>> +
>> +Required properties:
>> +- compatible : "snps,dw-apb-ssi"
>> +- reg : The register base for the controller. For "mscc,<soc>-spi", a second
>> + register set is required (named ICPU_CFG:SPI_MST)
>> +- #address-cells : <1>, as required by generic SPI binding.
>> +- #size-cells : <0>, also as required by generic SPI binding.
>> +- clocks : phandles for the clocks, see the description of clock-names below.
>> + The phandle for the "ssi_clk" is required. The phandle for the "pclk" clock
>> + is optional. If a single clock is specified but no clock-name, it is the
>> + "ssi_clk" clock. If both clocks are listed, the "ssi_clk" must be first.
>> +
>> +Optional properties:
>> +- clock-names : Contains the names of the clocks:
>> + "ssi_clk", for the core clock used to generate the external SPI clock.
>> + "pclk", the interface clock, required for register access.
>> +- cs-gpios : Specifies the gpio pins to be used for chipselects.
>> +- num-cs : The number of chipselects. If omitted, this will default to 4.
>> +- reg-io-width : The I/O register width (in bytes) implemented by this
>> + device. Supported values are 2 or 4 (the default).
>> +- snps,dfs-offset The offset in bits of the DFS field in CTRL0, defaulting to 0
>> +- snps,frf-offset The offset in bits of the FRF field in CTRL0, defaulting to 4
>> +- snps,tmod-offset The offset in bits of the tmode field in CTRL0, defaulting
>> + to 6
>> +- snps,mode-offset The offset in bits of the work mode field in CTRL0,
>> + defaulting to 8
>> +
>> +Child nodes as per the generic SPI binding.
>> +
>> +Example:
>> +
>> + spi at fff00000 {
>> + compatible = "snps,dw-apb-ssi";
>> + reg = <0xfff00000 0x1000>;
>> + interrupts = <0 154 4>;
>> + #address-cells = <1>;
>> + #size-cells = <0>;
>> + clocks = <&spi_m_clk>;
>> + num-cs = <2>;
>> + cs-gpios = <&gpio0 13 0>,
>> + <&gpio0 14 0>;
>> + };
>> diff --git a/drivers/spi/designware_spi.c b/drivers/spi/designware_spi.c
>> index 2dc16736a3..6e1c289297 100644
>> --- a/drivers/spi/designware_spi.c
>> +++ b/drivers/spi/designware_spi.c
>> @@ -3,6 +3,7 @@
>> * Designware master SPI core controller driver
>> *
>> * Copyright (C) 2014 Stefan Roese <sr@denx.de>
>> + * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
>> *
>> * Very loosely based on the Linux driver:
>> * drivers/spi/spi-dw.c, which is:
>> @@ -51,20 +52,14 @@
>> #define DW_SPI_DR 0x60
>>
>> /* Bit fields in CTRLR0 */
>> -#define SPI_DFS_OFFSET 0
>> -
>> -#define SPI_FRF_OFFSET 4
>> #define SPI_FRF_SPI 0x0
>> #define SPI_FRF_SSP 0x1
>> #define SPI_FRF_MICROWIRE 0x2
>> #define SPI_FRF_RESV 0x3
>>
>> -#define SPI_MODE_OFFSET 6
>> -#define SPI_SCPH_OFFSET 6
>> -#define SPI_SCOL_OFFSET 7
>> +#define SPI_MODE_SCPH 0x1
>> +#define SPI_MODE_SCOL 0x2
>>
>> -#define SPI_TMOD_OFFSET 8
>> -#define SPI_TMOD_MASK (0x3 << SPI_TMOD_OFFSET)
>> #define SPI_TMOD_TR 0x0 /* xmit & recv */
>> #define SPI_TMOD_TO 0x1 /* xmit only */
>> #define SPI_TMOD_RO 0x2 /* recv only */
>> @@ -89,6 +84,12 @@
>> struct dw_spi_platdata {
>> s32 frequency; /* Default clock frequency, -1 for none */
>> void __iomem *regs;
>> +
>> + /* Offsets in CTRL0 */
>> + u8 dfs_off;
>> + u8 frf_off;
>> + u8 tmod_off;
>> + u8 mode_off;
>> };
>>
>> struct dw_spi_priv {
>> @@ -115,6 +116,15 @@ struct dw_spi_priv {
>> struct reset_ctl_bulk resets;
>> };
>>
>> +static inline u32 GEN_CTRL0(struct dw_spi_priv *priv,
>> + struct dw_spi_platdata *plat)
>> +{
>> + return ((priv->bits_per_word - 1) << plat->dfs_off |
>> + (priv->type << plat->frf_off) |
>> + (priv->mode << plat->mode_off) |
>> + (priv->tmode << plat->tmod_off));
>> +}
>> +
>> static inline u32 dw_read(struct dw_spi_priv *priv, u32 offset)
>> {
>> return __raw_readl(priv->regs + offset);
>> @@ -160,6 +170,10 @@ static int dw_spi_ofdata_to_platdata(struct udevice *bus)
>> /* Use 500KHz as a suitable default */
>> plat->frequency = dev_read_u32_default(bus, "spi-max-frequency",
>> 500000);
>> + plat->dfs_off = dev_read_u32_default(bus, "snps,dfs-offset", 0);
>> + plat->frf_off = dev_read_u32_default(bus, "snps,frf-offset", 4);
>> + plat->mode_off = dev_read_u32_default(bus, "snps,mode-offset", 6);
>> + plat->tmod_off = dev_read_u32_default(bus, "snps,tmod-offset", 8);
>> debug("%s: regs=%p max-frequency=%d\n", __func__, plat->regs,
>> plat->frequency);
>>
>> @@ -388,6 +402,7 @@ static int dw_spi_xfer(struct udevice *dev, unsigned int bitlen,
>> const void *dout, void *din, unsigned long flags)
>> {
>> struct udevice *bus = dev->parent;
>> + struct dw_spi_platdata *plat = dev_get_platdata(bus);
>> struct dw_spi_priv *priv = dev_get_priv(bus);
>> const u8 *tx = dout;
>> u8 *rx = din;
>> @@ -406,10 +421,6 @@ static int dw_spi_xfer(struct udevice *dev, unsigned int bitlen,
>> if (flags & SPI_XFER_BEGIN)
>> external_cs_manage(dev, false);
>>
>> - cr0 = (priv->bits_per_word - 1) | (priv->type << SPI_FRF_OFFSET) |
>> - (priv->mode << SPI_MODE_OFFSET) |
>> - (priv->tmode << SPI_TMOD_OFFSET);
>> -
>> if (rx && tx)
>> priv->tmode = SPI_TMOD_TR;
>> else if (rx)
>> @@ -421,8 +432,7 @@ static int dw_spi_xfer(struct udevice *dev, unsigned int bitlen,
>> */
>> priv->tmode = SPI_TMOD_TR;
>>
>> - cr0 &= ~SPI_TMOD_MASK;
>> - cr0 |= (priv->tmode << SPI_TMOD_OFFSET);
>> + cr0 = GEN_CTRL0(priv, plat);
>>
>> priv->len = bitlen >> 3;
>> debug("%s: rx=%p tx=%p len=%d [bytes]\n", __func__, rx, tx, priv->len);
>> @@ -476,7 +486,7 @@ static int dw_spi_xfer(struct udevice *dev, unsigned int bitlen,
>>
>> static int dw_spi_set_speed(struct udevice *bus, uint speed)
>> {
>> - struct dw_spi_platdata *plat = bus->platdata;
>> + struct dw_spi_platdata *plat = dev_get_platdata(bus);
>> struct dw_spi_priv *priv = dev_get_priv(bus);
>> u16 clk_div;
>>
>> --
>> 2.25.0
>>