doc: shorten overlong title underlines

Title underlines should match the length of the title. Unfortunately
docutils only catches underlines that are too short.

Add some missing empty lines after titles.

Signed-off-by: Heinrich Schuchardt <[email protected]>

4 files changed, 12 insertions, 12 deletions

diff --git a/doc/develop/driver-model/ethernet.rst b/doc/develop/driver-model/ethernet.rst
index cdbccca34d6..73c3a728dbf 100644
--- a/doc/develop/driver-model/ethernet.rst
+++ b/doc/develop/driver-model/ethernet.rst
@@ -1,5 +1,5 @@
 Ethernet Driver Guide
-=======================
+=====================
 
 The networking stack in Das U-Boot is designed for multiple network devices
 to be easily added and controlled at runtime.  This guide is meant for people
@@ -14,7 +14,7 @@ Some drivers are still using the old Ethernet interface, differences between
 the two and hints about porting will be handled at the end.
 
 Driver framework
-------------------
+----------------
 
 A network driver following the driver model must declare itself using
 the UCLASS_ETH .id field in the U-Boot driver struct:
@@ -67,7 +67,7 @@ bus. Also it would take care of any special PHY setup (power rails, enable
 bits for internal PHYs, etc.).
 
 Driver methods
-----------------
+--------------
 
 The real work will be done in the driver method functions the driver provides
 by defining the members of struct eth_ops:
@@ -158,7 +158,7 @@ So the call graph at this stage would look something like:
 
 
 CONFIG_PHYLIB / CONFIG_CMD_MII
---------------------------------
+------------------------------
 
 If your device supports banging arbitrary values on the MII bus (pretty much
 every device does), you should add support for the mii command.  Doing so is
@@ -193,7 +193,7 @@ should logically follow.
 ................................................................
 
 Legacy network drivers
-------------------------
+----------------------
 
 !!! WARNING !!!
 
@@ -221,7 +221,7 @@ instructions on how to port this over. For the records, the old way of
 initialising a network driver is as follows:
 
 Old network driver registration
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 When U-Boot initializes, it will call the common function eth_initialize().
 This will in turn call the board-specific board_eth_init() (or if that fails,
diff --git a/doc/develop/driver-model/migration.rst b/doc/develop/driver-model/migration.rst
index fe1ae210def..03fea943b29 100644
--- a/doc/develop/driver-model/migration.rst
+++ b/doc/develop/driver-model/migration.rst
@@ -100,7 +100,7 @@ Maintainers should submit patches switching over to using CONFIG_DM_I2C and
 other base driver model options in time for inclusion in the 2021.10 release.
 
 CFG_SYS_TIMER_RATE and CFG_SYS_TIMER_COUNTER
---------------------------------------------------
+--------------------------------------------
 Deadline: 2023.01
 
 These are legacy options which have been replaced by driver model.
diff --git a/doc/develop/driver-model/nvmxip.rst b/doc/develop/driver-model/nvmxip.rst
index e85dc220b9c..4a7650c8d2f 100644
--- a/doc/develop/driver-model/nvmxip.rst
+++ b/doc/develop/driver-model/nvmxip.rst
@@ -1,7 +1,7 @@
 .. SPDX-License-Identifier: GPL-2.0+
 
 NVM XIP Block Storage Emulation Driver
-=======================================
+======================================
 
 Summary
 -------
@@ -54,12 +54,12 @@ The NVMXIP Uclass provides the following drivers:
 The implementation is generic and can be used by different platforms.
 
 Supported hardware
---------------------------------
+------------------
 
 Any plaform supporting readq().
 
 Configuration
-----------------------
+-------------
 
 config NVMXIP
 	  This option allows the emulation of a block storage device
@@ -77,7 +77,7 @@ config NVMXIP_QSPI
 	  write their own driver (same as nvmxip_qspi in addition to the custom settings).
 
 Device Tree nodes
---------------------
+-----------------
 
 Multiple QSPI XIP flash devices can be used at the same time by describing them through DT
 nodes.
diff --git a/doc/develop/driver-model/spi-howto.rst b/doc/develop/driver-model/spi-howto.rst
index 97fbf750cb6..9dc3b9b4aac 100644
--- a/doc/develop/driver-model/spi-howto.rst
+++ b/doc/develop/driver-model/spi-howto.rst
@@ -218,7 +218,7 @@ DM tells you. The name is not quite right. So in this case we would use:
 
 
 Write of_to_plat() [for device tree only]
--------------------------------------------------
+-----------------------------------------
 
 This method will convert information in the device tree node into a C
 structure in your driver (called platform data). If you are not using