dm: spi: Read default speed and mode values from DT

This patch update the behavior introduced by
commit 96907c0fe5 ("dm: spi: Read default speed and mode values from DT")

In case of DT boot, don't read default speed and mode for SPI from
CONFIG_* but instead read from DT node. This will make sure that boards
with multiple SPI/QSPI controllers can be probed at different
bus frequencies and SPI modes.

Remove also use in boards of the value speed=0 (no more supported)
for ENV in SPI by using CONFIG_ENV_SPI_MAX_HZ=0.

DT values will be always used when available (full DM support of
SPI slave with available DT node) even if speed and mode are requested;
for example in splash screen support (in splash_sf_read_raw)
or in SPL boot (in spl_spi_load_image).
The caller of spi_get_bus_and_cs() no more need to force speed=0.

But the current behavior don't change if the SPI slave is not
present (device with generic driver is created automatically)
or if platdata is used (CONFIG_OF_PLATDATA).

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Acked-by: Jagan Teki <jagan@amarulasolutions.com>

cmd/sf.c

@@ -81,14 +81,13 @@ static int do_spi_flash_probe(int argc, char * const argv[])
 {
 	unsigned int bus = CONFIG_SF_DEFAULT_BUS;
 	unsigned int cs = CONFIG_SF_DEFAULT_CS;
+	/* In DM mode, defaults speed and mode will be taken from DT */
 	unsigned int speed = CONFIG_SF_DEFAULT_SPEED;
 	unsigned int mode = CONFIG_SF_DEFAULT_MODE;
 	char *endp;
 #ifdef CONFIG_DM_SPI_FLASH
 	struct udevice *new, *bus_dev;
 	int ret;
-	/* In DM mode defaults will be taken from DT */
-	speed = 0, mode = 0;
 #else
 	struct spi_flash *new;
 #endif

common/spl/spl_spi.c

@@ -77,6 +77,8 @@ static int spl_spi_load_image(struct spl_image_info *spl_image,
 
 	/*
 	 * Load U-Boot image from SPI flash into RAM
+	 * In DM mode: defaults speed and mode will be
+	 * taken from DT when available
 	 */
 
 	flash = spi_flash_probe(CONFIG_SF_DEFAULT_BUS,

configs/da850_am18xxevm_defconfig

@@ -39,10 +39,6 @@ CONFIG_SPL_OF_CONTROL=y
 CONFIG_DEFAULT_DEVICE_TREE="da850-evm"
 CONFIG_SPL_OF_PLATDATA=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_DM=y
 CONFIG_SPL_DM=y
 CONFIG_DA8XX_GPIO=y

configs/da850evm_defconfig

@@ -41,10 +41,6 @@ CONFIG_SPL_OF_CONTROL=y
 CONFIG_DEFAULT_DEVICE_TREE="da850-evm"
 CONFIG_SPL_OF_PLATDATA=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_DM=y
 CONFIG_SPL_DM=y
 CONFIG_DM_GPIO=y

configs/mscc_jr2_defconfig

@@ -38,10 +38,6 @@ CONFIG_OF_LIST="jr2_pcb110 jr2_pcb111 serval2_pcb112"
 CONFIG_DTB_RESELECT=y
 CONFIG_MULTI_DTB_FIT=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_CLK=y
 CONFIG_DM_GPIO=y

configs/mscc_luton_defconfig

@@ -44,10 +44,6 @@ CONFIG_OF_LIST="luton_pcb090 luton_pcb091"
 CONFIG_DTB_RESELECT=y
 CONFIG_MULTI_DTB_FIT=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_CLK=y
 CONFIG_DM_GPIO=y

configs/mscc_ocelot_defconfig

@@ -43,10 +43,6 @@ CONFIG_OF_LIST="ocelot_pcb120 ocelot_pcb123"
 CONFIG_DTB_RESELECT=y
 CONFIG_MULTI_DTB_FIT=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_CLK=y
 CONFIG_DM_GPIO=y

configs/mscc_serval_defconfig

@@ -35,10 +35,6 @@ CONFIG_OF_LIST="serval_pcb106 serval_pcb105"
 CONFIG_DTB_RESELECT=y
 CONFIG_MULTI_DTB_FIT=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_CLK=y
 CONFIG_DM_GPIO=y

configs/mscc_servalt_defconfig

@@ -33,10 +33,6 @@ CONFIG_DEFAULT_DEVICE_TREE="servalt_pcb116"
 CONFIG_DTB_RESELECT=y
 CONFIG_MULTI_DTB_FIT=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
-CONFIG_USE_ENV_SPI_MAX_HZ=y
-CONFIG_ENV_SPI_MAX_HZ=0
-CONFIG_USE_ENV_SPI_MODE=y
-CONFIG_ENV_SPI_MODE=0
 CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_CLK=y
 CONFIG_DM_GPIO=y

drivers/mtd/spi/Kconfig

@@ -62,6 +62,9 @@ config SF_DEFAULT_MODE
 	  The default mode may be provided by the platform
 	  to handle the common case when only a single serial
 	  flash is present on the system.
+	  Not used for boot with device tree; the SPI driver reads
+	  speed and mode from platdata values computed from
+	  available node.
 
 config SF_DEFAULT_SPEED
 	int "SPI Flash default speed in Hz"
@@ -71,6 +74,9 @@ config SF_DEFAULT_SPEED
 	  The default speed may be provided by the platform
 	  to handle the common case when only a single serial
 	  flash is present on the system.
+	  Not used for boot with device tree; the SPI driver reads
+	  speed and mode from platdata values computed from
+	  available node.
 
 if SPI_FLASH
 

drivers/spi/spi-uclass.c

@@ -328,7 +328,9 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 	}
 
 	plat = dev_get_parent_platdata(dev);
-	if (!speed) {
+
+	/* get speed and mode from platdata when available */
+	if (plat->max_hz) {
 		speed = plat->max_hz;
 		mode = plat->mode;
 	}

include/spi.h

@@ -496,14 +496,15 @@ int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
  * device and slave device.
  *
  * If no such slave exists, and drv_name is not NULL, then a new slave device
- * is automatically bound on this chip select.
+ * is automatically bound on this chip select with requested speed and mode.
  *
- * Ths new slave device is probed ready for use with the given speed and mode.
+ * Ths new slave device is probed ready for use with the speed and mode
+ * from platdata when available or the requested values.
  *
  * @busnum:	SPI bus number
  * @cs:		Chip select to look for
- * @speed:	SPI speed to use for this slave
- * @mode:	SPI mode to use for this slave
+ * @speed:	SPI speed to use for this slave when not available in platdata
+ * @mode:	SPI mode to use for this slave when not available in platdata
  * @drv_name:	Name of driver to attach to this chip select
  * @dev_name:	Name of the new device thus created
  * @busp:	Returns bus device