diff --git a/Documentation/util.md b/Documentation/util.md
index f902ba4fdd..e6d1402c8a 100644
--- a/Documentation/util.md
+++ b/Documentation/util.md
@@ -70,8 +70,8 @@ into a format which can be used in coreboot's verb table `Go`
 `C`
 * __intelmetool__ - Dump interesting things about Management Engine
 even if hidden `C`
-* __intelp2m__ - convert the configuration DW0/1 registers value from
-an inteltool dump to coreboot macros. `go`
+* __intelp2m__ - Convert the inteltool register dump to gpio.h with GPIO
+configuration for porting coreboot to your motherboard. `Go`
 * __inteltool__ - Provides information about the Intel CPU/chipset
 hardware configuration (register contents, MSRs, etc). `C`
 * __intelvbttool__ - Parse VBT from VGA BIOS `C`
diff --git a/Documentation/util/intelp2m/gopackages.png b/Documentation/util/intelp2m/gopackages.png
deleted file mode 100644
index fb81a1ce1f..0000000000
Binary files a/Documentation/util/intelp2m/gopackages.png and /dev/null differ
diff --git a/Documentation/util/intelp2m/index.md b/Documentation/util/intelp2m/index.md
index 98b9c009d6..dd7994e19c 100644
--- a/Documentation/util/intelp2m/index.md
+++ b/Documentation/util/intelp2m/index.md
@@ -1,210 +1,273 @@
 Intel Pad to Macro (intelp2m) converter
 =======================================
 
-This utility allows one to convert the configuration DW0/1 register
-values from an inteltool dump to coreboot macros.
+The utility generates `output/gpio.h` with the GPIO configuration for SoC or PCH from intel.
+Use it to create coreboot port for your motherboard in the `src/mainboard/your-motherboard`
+directory. Depending on the settings, you can create several configuration formats:
+- [coreboot macros](../../getting_started/gpio.md);
+- [Intel FSP macros](../../soc/intel/fsp/index.md).
+
+Installing the latest version:
+
+```bash
+go install review.coreboot.org/coreboot.git/util/intelp2m@master
+```
+
+Including in the project as an external library:
+
+```bash
+go get review.coreboot.org/coreboot.git/util/intelp2m@master
+```
+
+## Build
+
+Since the utility is written in Go, you need to install the official
+[go-compiler and go-tools](https://go.dev/dl/) to build the executive
+image.
 
 ```bash
 cd util/intelp2m
 make
+./intelp2m -version
+```
+
+Set automatic argument completion:
+
+```bash
+complete -C `pwd`/intelp2m ./intelp2m
+```
+
+## Demo
+
+```bash
+./intelp2m -platform snr -file parser/testlog/inteltool_test.log
+```
+
+## Input data
+
+The chipset register dump obtained using [inteltool](../../util.md) is used as input data.
+
+```bash
+cd util/inteltool
+make
+sudo ./inteltool -G > inteltool.log
+```
+
+After this step, you can generate `gpio.h`:
+
+```bash
+./intelp2m -file ../inteltool/inteltool.log
+```
+
+More details in the help:
+
+```bash
 ./intelp2m -h
-./intelp2m -file /path/to/inteltool.log
 ```
 
 ## Platforms
 
-It is possible to use templates for parsing inteltool.log files.
-To specify such a pattern, use the option `-t <template number>`.
+The utility supports the following chipsets from Intel:
 
-```text
-    -t
-    template type number
-        0 - inteltool.log (default)
-        1 - gpio.h
-        2 - your template
-```
+* `adl` - Alder Lake PCH
+* `apl` - Apollo Lake SoC
+* `cnl` - CannonLake-LP or Whiskeylake/Coffeelake/Cometlake-U SoC
+* `ebg` - Emmitsburg PCH with Xeon SP
+* `jsl` - Jasper Lake SoC
+* `lbg` - Lewisburg PCH with Xeon SP
+* `mtl` - MeteorLake SoC
+* `snr` - Sunrise PCH or Skylake/Kaby Lake SoC
+* `tgl` - TigerLake-H SoC
 
-For example, using template type 1, you can parse gpio.h from an
-existing board in the coreboot project.
+The `-platform` option allows you to identify one of the above platforms:
 
 ```bash
-./intelp2m -t 1 -file coreboot/src/mainboard/yourboard/gpio.h
+./intelp2m -platform <platform> -file path/to/inteltool.log
 ```
 
-You can also add a template to 'parser/template.go' for your file type
-with the configuration of the pads.
+Show more details:
 
-platform type is set using the -p option (Sunrise by default):
+```bash
+./intelp2m -platform ?
+```
 
-```text
--p string
-  set up a platform
-    snr - Sunrise PCH with Skylake/Kaby Lake CPU
-    lbg - Lewisburg PCH with Xeon SP CPU
-    apl - Apollo Lake SoC
-    cnl - CannonLake-LP or Whiskeylake/Coffeelake/Cometlake-U SoC
-    adl - AlderLake PCH
-  (default "snr")
+## Auto-check macro
+
+The utility automatically checks the bit fields of the GPIO registers before generating the macro.
+If the bit is set to 1 in a register but isn't used in the "short" macro, the "long" macro is
+generated. This avoids data loss in the configuration.
+
+```c
+// the "short" macro:
+PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1, TxLASTRxE, DISPUPD),
+
+// the "long" macro:
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
+
+// [*] PAD_TRIG(OFF) isn't used in the "short" macro.
+```
+
+The option `-u`, `-unchecked` is used to disable automatic verification.
+In this case, all macros in `gpio.h` are generated in the "short" format:
+
+```c
+...
+PAD_NC(GPP_F18, NONE),
+PAD_CFG_NF(GPP_F19, NONE, PLTRST, NF1),
+...
 ```
 
 ```bash
-./intelp2m -p <platform> -file path/to/inteltool.log
+./intelp2m -unchecked -platform apl -file path/to/inteltool.log
+```
+
+## Excluding fields from the macro
+
+The utility can generate "long" macros without fields that aren't used in "short" ones.
+The `-e`, `-exclude` option is used to exclude these fields from the generated macros in
+`gpio.h`:
+
+```bash
+./intelp2m -exclude -platform apl -file path/to/inteltool.log
+```
+
+```c
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
+
+// [*] PAD_TRIG(OFF) field was excluded from the "long" macro.
 ```
 
 ## Packages
 
-![][pckgs]
+```text
++-------------------------------------------------------------------+
+|                              main                                 |
++-------------------------------------------------------------------+
+                         |                 |                 |
+                         V                 V                 V
++------------+   +--------------+   +-------------+   +-------------+
+|  template  |<--|    parser    |   |  generator  |   |   printer   |
++------------+   +--------------+   +-------------+   +-------------+
+                         |
+                         V
++-------------------------------------------------------------------+
+|                           platforms                               |
++-------------------------------------------------------------------+
+    |          |          |          |          |               |
+    V          V          V          V          V               V
++-------+  +-------+  +-------+  +-------+  +-------+       +-------+
+|  adl  |  |  apl  |  |  cnl  |  |  lbg  |  |  snr  | * * * | other |
++-------+  +-------+  +-------+  +-------+  +-------+       +-------+
+    |          |          |          |          |               |
+    V          V          V          V          V               V
++-------------------------------------------------------------------+
+|                             common                                |
++-------------------------------------------------------------------+
+                  |                           |              |
+                  V                           |              |
++------------------------------------+        |              |
+|               fields               |        |              |
++------------------------------------+        |              |
+     |            |             |             |              |
+     V            V             V             V              V
++--------+   +---------+   +---------+  +-----------+  +------------+
+|   cb   |   |   raw   |   |   fsp   |  |   macro   |  |  register  |
++--------+   +---------+   +---------+  +-----------+  +------------+
+```
 
-[pckgs]: gopackages.png
+## Format
 
-## Bit fields in macros
-
-Use the `-fld=cb` option to only generate a sequence of bit fields in
-a new macro:
+Depending on the options -i, -ii, -iii, -iiiii (information level),
+the utility can generate the configuration in different formats:
 
 ```bash
-./intelp2m -fld cb -p apl -file ../apollo-inteltool.log
+./intelp2m [-i | -ii | -iii | -iiii] -platform apl -file path/to/inteltool.log
 ```
 
+* i adding a function name:
+
 ```c
-_PAD_CFG_STRUCT(GPIO_37, PAD_FUNC(NF1) | PAD_TRIG(OFF) | PAD_TRIG(OFF), \
-    PAD_PULL(DN_20K)), /* LPSS_UART0_TXD */
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)), /* LPSS_UART0_TXD */
 ```
 
-## Raw DW0, DW1 register value
-
-To generate the gpio.c with raw PAD_CFG_DW0 and PAD_CFG_DW1 register
-values you need to use the -fld=raw option:
-
-```bash
-./intelp2m -fld raw -file /path/to/inteltool.log
-```
-
-```c
-_PAD_CFG_STRUCT(GPP_A10, 0x44000500, 0x00000000),
-```
-
-```bash
-./intelp2m -iiii -fld raw -file /path/to/inteltool.log
-```
-
-```c
-/* GPP_A10 - CLKOUT_LPC1 */
-/* DW0: 0x44000500, DW1: 0x00000000 */
-/* DW0: 0x04000100 - IGNORED */
-/* PAD_CFG_NF(GPP_A10, NONE, DEEP, NF1), */
-_PAD_CFG_STRUCT(GPP_A10, 0x44000500, 0x00000000),
-```
-
-## Macro Check
-
-After generating the macro, the utility checks all used
-fields of the configuration registers. If some field has been
-ignored, the utility generates field macros. To not check
-macros, use the -n option:
-
-```bash
-./intelp2m -n -file /path/to/inteltool.log
-```
-
-In this case, some fields of the configuration registers
-DW0 will be ignored.
-
-```c
-PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_38, UP_20K, DEEP, NF1, HIZCRx1, DISPUPD),
-PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1, TxLASTRxE, DISPUPD),
-```
-
-## Information level
-
-The utility can generate additional information about the bit
-fields of the DW0 and DW1 configuration registers. Using the
-options -i, -ii, -iii, -iiii you can set the info level from
-1 to 4:
-
-```bash
-./intelp2m -i -file /path/to/inteltool.log
-```
-
-```c
-_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF),\
-    PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),    /* LPSS_UART0_TXD */
-```
-
-```bash
-./intelp2m -ii -file /path/to/inteltool.log
-./intelp2m -iii -file /path/to/inteltool.log
-./intelp2m -iiii -file /path/to/inteltool.log
-```
+* ii adds configuration register values:
 
 ```c
 /* GPIO_39 - LPSS_UART0_TXD */
-/* DW0: 0x44000400, DW1: 0x00003100 */ --> (ii)
-/* DW0 : PAD_TRIG(OFF) - IGNORED */ --> (iii)
-/* PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1, TxLASTRxE,
-   DISPUPD), */ --> (iiii)
-_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF),
-    PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
+/* DW0: 0x44000400, DW1: 0x00003100 */
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
 ```
 
-If the -n switch was used and macros was generated without checking:
+* iii adds information about ignored fields:
+
 ```c
-/* GPIO_39 - LPSS_UART0_TXD */ --> (i)
-/* DW0: 0x44000400, DW1: 0x00003100 */ --> (ii)
-/* DW0: PAD_TRIG(OFF) - IGNORED */ --> (iii)
-/* _PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) |
-  PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)), */ --> (iiii)
-PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1, TxLASTRxE, \
-    DISPUPD),
+/* GPIO_39 - LPSS_UART0_TXD */
+/* DW0: 0x44000400, DW1: 0x00003100 */
+/* DW0 : PAD_TRIG(OFF) - IGNORED */
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
 ```
 
-## Ignoring Fields
-
-Utilities can generate the _PAD_CFG_STRUCT macro and exclude fields
-from it that are not in the corresponding PAD_CFG_*() macro:
-
-```bash
-./intelp2m -iiii -fld cb -ign -file /path/to/inteltool.log
-```
+* iiii adds the "short" macro corresponding to the current one (possibly after excluding unused fields):
 
 ```c
 /* GPIO_39 - LPSS_UART0_TXD */
 /* DW0: 0x44000400, DW1: 0x00003100 */
 /* DW0: PAD_TRIG(OFF) - IGNORED */
-/* PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1,
-   TxLASTRxE, DISPUPD), */
-_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP), \
-    PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
+/* PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1, TxLASTRxE, DISPUPD), */
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
 ```
 
-## FSP-style macro
-
-The utility allows one to generate macros that include fsp/edk2-platform
-style bitfields:
-
-```bash
-./intelp2m -i -fld fsp -p lbg -file ../crb-inteltool.log
-```
+The same without automatic check:
 
 ```c
-{ GPIO_SKL_H_GPP_A12, { GpioPadModeGpio, GpioHostOwnAcpi, GpioDirInInvOut,
-  GpioOutLow, GpioIntSci | GpioIntLvlEdgDis, GpioResetNormal, GpioTermNone,
-  GpioPadConfigLock },    /* GPIO */
+/* GPIO_39 - LPSS_UART0_TXD */
+/* DW0: 0x44000400, DW1: 0x00003100 */
+/* DW0: PAD_TRIG(OFF) - IGNORED */
+/* _PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)), */
+PAD_CFG_NF_IOSSTATE_IOSTERM(GPIO_39, UP_20K, DEEP, NF1, TxLASTRxE, DISPUPD),
 ```
 
+iiii generates an original macro in the comments.
+
+## Long macros with fields collection
+
+Depending on the value of the option -fields, the utility can generate
+long macros with different styles of the field collection:
+
 ```bash
-./intelp2m -iiii -fld fsp -p lbg -file ../crb-inteltool.log
+./intelp2m -fields [fsp | cb | raw] -platform apl -file ../apollo-inteltool.log
 ```
 
+* fsp
+
 ```c
-/* GPP_A12 - GPIO */
-/* DW0: 0x80880102, DW1: 0x00000000 */
-/* PAD_CFG_GPI_SCI(GPP_A12, NONE, PLTRST, LEVEL, INVERT), */
-{ GPIO_SKL_H_GPP_A12, { GpioPadModeGpio, GpioHostOwnAcpi, GpioDirInInvOut,
-  GpioOutLow, GpioIntSci | GpioIntLvlEdgDis, GpioResetNormal, GpioTermNone,
-  GpioPadConfigLock },
+{ GPIO_SKL_H_GPP_A12, { GpioPadModeGpio, GpioHostOwnAcpi, GpioDirInInvOut, GpioOutLow, GpioIntSci | GpioIntLvlEdgDis, GpioResetNormal GpioTermNone, GpioPadConfigLock },
 ```
 
-## Supported Chipsets
+* cb
 
-  Sunrise PCH, Lewisburg PCH, Apollo Lake SoC, CannonLake-LP SoCs
+```c
+_PAD_CFG_STRUCT(GPIO_39, PAD_FUNC(NF1) | PAD_RESET(DEEP) | PAD_TRIG(OFF), PAD_PULL(UP_20K) | PAD_IOSTERM(DISPUPD)),
+```
+
+* raw
+
+```c
+_PAD_CFG_STRUCT(GPP_A10, 0x44000500, 0x00000000),
+```
+
+Show more details:
+
+```bash
+./intelp2m -fields ?
+```
+
+## Unit testing
+
+Please run the tests before creating a new commit:
+
+```bash
+make test
+```
+
+If successful, all tests contain the PASS prefix.
diff --git a/util/README.md b/util/README.md
index 7a98bb6061..6d58d7a71b 100644
--- a/util/README.md
+++ b/util/README.md
@@ -61,8 +61,8 @@ into a format which can be used in coreboot's verb table `Go`
 `C`
 * __intelmetool__ - Dump interesting things about Management Engine
 even if hidden `C`
-* __intelp2m__ - convert the configuration DW0/1 registers value from
-an inteltool dump to coreboot macros. `go`
+* __intelp2m__ - Generate a GPIO configuration based on a register dump
+obtained using inteltool. `Go`
 * __inteltool__ - Provides information about the Intel CPU/chipset
 hardware configuration (register contents, MSRs, etc). `C`
 * __intelvbttool__ - Parse VBT from VGA BIOS `C`