Supported Hardware¶
The main hardware used is Intel Validation Platform (RVP) used in conjunction with a modular embedded control card (MECC) or when applicable the on-board EC.
The reference HW used to showcase EC FW open source takes advantage of the Modular Embedded controller card (MECC) specification, which defines both pin mapping and provides general guidelines to use different Embedded Controller Soc to the on-board EC through an add-on card. This allows to evaluate different EC in an Intel RVP.
Note
Reworks are required on RVP to be able to control the RVP from MECC card. Refer to Platform design guide for details.
Board |
EC HW configuration |
Support |
|---|---|---|
Meteorlake S |
RVP (on-board EC) |
|
Meteorlake P |
RVP (on-board EC) |
Recommended |
Meteorlake P |
RVP + MECC card |
Enable other EC vendor |
Other EC SoC¶
In order to use a different MECC card with a different EC SoC vendor, the vendor should add its Hardware Abstraction Layer (HAL) and board support package (BSP) to Zephyr RTOS. See Zephyr’s porting guide
The list below presents the minimum drivers required by the EC application to boot an eSPI-based Intel platform.
UART
GPIO
RTOS timer
I2C - Port 80 visualization if board supports it.
eSPI - Required by power sequencing module
ACPI - Required by SMC host module (EC - BIOS interactions).
The following drivers are needed to exercise other non-boot critical features:
PS/2 - for PS/2 devices management
Keyscan - for keyboard matrix
These drivers are required to enable advanced features such as thermal and fan control.
PECI - for thermal module
TACH - for thermal module
ADC - for thermal module
PWM - for fan control
Customize EC FW framework for other EC SoC¶
Zephyr uses device tree to describe hardware both EC SoC and board’s peripherals. The EC FW abstracts the device tree using friendly macros which can be customized when using different EC SoC and/or different board. See boards/<vendor> for more details
#define I2C_BUS_0 DT_NODELABEL(i2c_smb_0)
For more details, see Zephyr’s device tree guide.
GPIO initialization¶
EC FW app doesn’t control/configure all GPIOs on the chip but only the ones used by the app. This is an important delegation to BSP’s where generic app pins are not configured.
Note
For current supported HW via MECC card, see boards folder.
When a pin is intended to be controlled by the EC FW framework it should be mapped under boardname_chipversion.h to corresponding Zephyr GPIO port and pin.
#define PCH_PWROK EC_GPIO_106 /* Board #1 Port A, Pin B */
#define PCH_PWROK EC_GPIO_036 /* Board #2 Port B, Pin C */
Note
EC_GPIO_XXX is a SoC specific macro, which abstracts GPIO port and GPIO pin number since Zephyr supports logical GPIO ports and EC FW requires the flexibility to map a signal to different pins.
Similarly, boardname_chipversion.c should contain the actual pin configuration required by the application input/output, open drain and so on. See Zephyr’s GPIO reference for Zephyr GPIO flags.
HW limitations¶
Most of the signals used by onboard EC are routed to MECC connector, however some signals may be missing on MECC compared to onboard EC. Refer to RVP schematics.
Note
Additionally, some MECC cards implement some variations on the MECC spec. However, this is being addressed by discussing with the EC vendors to adhere to the spec allowing more consistency.
As indicated above some Intel RVP features available are reduced when using MECC card. Refer to table below for guidance about what can be verified end-to-end.
Area |
Feature |
MTL-P + MEC172x |
MTL-S onboard |
MTL-P onboard |
|---|---|---|---|---|
Power sequencing |
ACPI power (Sx) |
Yes |
Yes |
Yes |
Deep sleep (DSx) |
No |
Yes |
No |
|
Pseudo G3 |
No |
No |
Yes |
|
SAF |
No |
Yes |
Yes |
|
Human interface |
Volume buttons |
Yes |
Yes |
Yes |
Power button |
Yes |
Yes |
Yes |
|
Home button |
No |
No |
Yes |
|
Lid switch |
Yes |
No |
Yes |
|
Thermal |
CPU temperature reading |
Yes |
Yes |
Yes |
Fan control |
Yes |
Yes |
Yes |
|
PS2/ scan matrix |
PS2 keyboard |
Yes |
Yes |
Yes(2) |
PS2 mouse |
No (1) |
No |
Yes(2) |
|
Keyboard matrix |
Yes(3) |
Yes |
Yes |
|
Debug |
Port 80 |
Yes |
Yes |
Yes |
Serial port (UART) |
Yes(4) |
Yes |
Yes |
Note
(1) MEC172x HW revision 2 supports PS2 Keyboard on PortA and PS2 Mouse on PortB. Mouse has not been verified though.
Note
(2) There is no PS2 connector on the MTL-P board, instead there is 1x5 header that allow the connection.
Note
(3) Intel Meteorlake RVP keyboard matrix connector cannot be used, instead need to connect the keyboard matrix directly into the MECC card. MEC15xx/MEC17xx cards allow to use Fujitsu keyboard matrix.
Note
(4) Intel Meteorlake RVP UART connector cannot be used for EC serial logs. Use MECC USB instead.