soc/amd/picasso: Remove xhci0_force_gen1 from soc config

To remove the xhci0_force_gen1 and use usb3_port_force_gen1 instead.
The xhci0_force_gen1 is used for force all port on xhci0 to USB3 GEN1.
Now variant can use the usb3_port_force_gen1 to customize which port
it needs to limit.

BUG=b:167651308
BRANCH=zork
TEST=Build, verify the USB3 speed in gen1

Signed-off-by: Chris Wang <chris.wang@amd.corp-partner.google.com>
Change-Id: If5f0c1f22d8c98c4461f09d074bf082c340b14d9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46041
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-by: Sam McNally <sammc@google.com>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

src/mainboard/google/zork/variants/baseboard/devicetree_dalboz.cb

@@ -54,8 +54,6 @@ chip soc/amd/picasso
 		.init_khz_preset = 1,
 	}"
 
-	register "xhci0_force_gen1" = "0"
-
 	register "has_usb2_phy_tune_params" = "1"
 
 	# Controller0 Port0 Default

src/mainboard/google/zork/variants/baseboard/devicetree_trembyle.cb

@@ -54,8 +54,6 @@ chip soc/amd/picasso
 		.init_khz_preset = 1,
 	}"
 
-	register "xhci0_force_gen1" = "0"
-
 	register "has_usb2_phy_tune_params" = "1"
 
 	# Controller0 Port0 Default

src/soc/amd/picasso/chip.h

@@ -201,8 +201,7 @@ struct soc_amd_picasso_config {
 		 */
 		uint16_t init_khz_preset;
 	} emmc_config;
-	/* set xhci0 from gen2 to gen1 */
-	uint8_t xhci0_force_gen1;
+
 	/* Force USB3 port to gen1, bit0 - controller0 Port0, bit1 - Port1 */
 	union usb3_force_gen1 usb3_port_force_gen1;
 

src/soc/amd/picasso/fsp_params.c

@@ -110,7 +110,6 @@ static void fsp_usb_oem_customization(FSP_S_CONFIG *scfg,
 	/* each OC mapping in xhci_oc_pin_select is 4 bit per USB port */
 	ASSERT(2 * sizeof(scfg->xhci_oc_pin_select) >= USB_PORT_COUNT);
 
-	scfg->xhci0_force_gen1 = cfg->xhci0_force_gen1;
 	scfg->fch_usb_3_port_force_gen1 = cfg->usb3_port_force_gen1.usb3_port_force_gen1_en;
 
 	if (cfg->has_usb2_phy_tune_params) {