diff options
| author | Mario Scheithauer <mario.scheithauer@siemens.com> | 2023-06-28 10:18:29 +0200 |
|---|---|---|
| committer | Felix Held <felix-coreboot@felixheld.de> | 2023-07-03 12:48:33 +0000 |
| commit | 15e1d97463f8ae21010f6f6bf38659b6cae718b2 (patch) | |
| tree | 0d6d20050e29cf25cf589d109143943dc3e2c01c /src/mainboard | |
| parent | b34576b03bc9034843969505d6193ea22837e36c (diff) | |
mb/siemens/mc_apl5: Correct the Tx signal from SATA port 0
Because of an incorrect transmit voltage swing, the signal must be
adjusted. The factor of slices for full swing level can be corrected via
the High Speed I/O Transmit Control Register 3. The appropriate value of
0.7 V was determined by using an oscilloscope.
Change-Id: I965960004ca44f1b37b16ce6484000fa7fd8ad90
Signed-off-by: Mario Scheithauer <mario.scheithauer@siemens.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/76175
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jan Samek <jan.samek@siemens.com>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
Diffstat (limited to 'src/mainboard')
| -rw-r--r-- | src/mainboard/siemens/mc_apl1/variants/mc_apl5/mainboard.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/src/mainboard/siemens/mc_apl1/variants/mc_apl5/mainboard.c b/src/mainboard/siemens/mc_apl1/variants/mc_apl5/mainboard.c index 1e7fa37cf8..8eedce6d6c 100644 --- a/src/mainboard/siemens/mc_apl1/variants/mc_apl5/mainboard.c +++ b/src/mainboard/siemens/mc_apl1/variants/mc_apl5/mainboard.c @@ -13,6 +13,9 @@ #include <baseboard/variants.h> #include <types.h> +#define TX_DWORD3_P0 0xc8c +#define TX_SWING_MASK 0x00ff0000 + void variant_mainboard_final(void) { struct device *dev = NULL; @@ -32,6 +35,14 @@ void variant_mainboard_final(void) */ pcr_or32(PID_LPC, PCR_LPC_PRC, (PCR_LPC_CCE_EN | PCR_LPC_PCE_EN)); + /* + * Correct the SATA transmit signal via the High Speed I/O Transmit + * Control Register 3 on SATA port 0. + * Bit [23:16] sets the output voltage swing for TX line. + * The value 0x5a sets the swing level to 0.7 V. + */ + pcr_rmw32(PID_MODPHY, TX_DWORD3_P0, ~TX_SWING_MASK, 0x5a << 16); + /* Set Master Enable for on-board PCI device if allowed. */ dev = dev_find_device(PCI_VID_SIEMENS, 0x403e, 0); if (dev) { |