At the beginning I would like to thank you for all your assistance and help with mainstream Linux kernel compilation and deployment. I have successfully deployed and run 4.6.2 Linux kernel. The good news is, that Linux is running and Ethernet is working. Whats worry me is poor PCIe devices list. I cannot see any mini-PCIe devices connected to the mini-PCIe slot. PCI devices list with Toradex Linux kernel 3.1.10:
Due to an errata of the PCIe switch on our EvaluationBoard its reset line is connected to Apalis GPIO7 and needs to be toggled well in advance of releasing the regular RESET_MOCI signal. While this is taken care of by our regular BSP’s kernel here this is rather tricky to implement properly in mainline. The easiest would therefore probably be to do this in U-Boot as indicated here.
Depending on your device you might further have to limit it to GEN1 speed but let’s first see how you get along with it.
OK, well the uPD720202 probably does GEN2 which is not really supported by the T30 SoC plus our EvaluationBoard design probably is not GEN2 compliant neither. You would therefore have to make sure it exclusively uses GEN1 e.g. as follows.
BTW: Something else one could try is on a Ixora carrier board where its mini-PCIe slot is realised straight off the Apalis module without any PCIe switch or anything in between.
Because I`m unexperienced in hacking kernels I would like to ask what is your suggestion for this modification? Is it better to do this on the kernel side like in your custom kernel by adding Macro DECLARE_PCI_FIXUP_EARLY and function quirk_apalis_plx_gen1 to the new arch/arm/mach-tegra/… file or is it better to do that in u-boot? I tried to do that in u-boot, by adding: pci_write_config_dword(0x8605, 0x98, 0x01);
diff --git a/board/toradex/apalis_t30/apalis_t30.c b/board/toradex/apalis_t30/apalis_t30.c
index 9f9731a..2ee612f 100644
--- a/board/toradex/apalis_t30/apalis_t30.c
+++ b/board/toradex/apalis_t30/apalis_t30.c
@@ -77,6 +77,7 @@ void pinmux_init(void)
ARRAY_SIZE(apalis_t30_padctrl));
}
+
#ifdef CONFIG_PCI_TEGRA
int tegra_pcie_board_init(void)
{
@@ -120,6 +121,34 @@ int tegra_pcie_board_init(void)
return err;
}
+#ifdef APALIS_T30_PCIE_EVALBOARD_INIT
+#define PEX_PERST_N GPIO_PS7 /* Apalis GPIO7 */
+#define RESET_MOCI_N GPIO_PI4
+
+
+ /* Reset PLX PEX 8605 PCIe Switch plus PCIe devices on Apalis Evaluation
+ Board */
+ gpio_request(PEX_PERST_N, "PEX_PERST_N");
+ gpio_request(RESET_MOCI_N, "RESET_MOCI_N");
+ gpio_direction_output(PEX_PERST_N, 0);
+ gpio_direction_output(RESET_MOCI_N, 0);
+ /* Must be asserted for 100 ms after power and clocks are stable */
+ mdelay(100);
+ gpio_set_value(PEX_PERST_N, 1);
+ /* Err_5: PEX_REFCLK_OUTpx/nx Clock Outputs is not Guaranteed Until
+ 900 us After PEX_PERST# De-assertion */
+ mdelay(1);
+ gpio_set_value(RESET_MOCI_N, 1);
+
+ /* The Apalis evaluation board needs to set the link speed to 2.5 GT/s (GEN1).
+ The default link speed setting is 5 GT/s (GEN2). 0x98 is the Link Control 2
+ PCIe Capability Register of the PEX8605 PCIe switch. The switch supports
+ link speed auto negotiation, but falsely sets the link speed to 5 GT/s. */
+ pci_write_config_dword(0x8605, 0x98, 0x01);
+ mdelay(50);
+
+#endif /* APALIS_T30_PCIE_EVALBOARD_INIT */
+
return 0;
}
but it looks, like is not working. There is an error during u-boot starting: pci_bus_to_hose() failed
Could you point me out on a proper way? Thank you in advance for the assistance.
I don’t know how to add any such to U-Boot plus our rather old U-Boot version has some issues with PCIe switch enumeration as far as I remember. The easiest would probably be to add it to the drivers/pci/quirks.c file similar as to the Tilera one as shown.
but still cannot see uPD720202 device. The question is if I did something wrong or problem lies elsewhere? In attachment full dmesg log and lspci -vv log link text. Any another ideas? Many thanks for your assistance.
Yes this card was perfeclty working on the same hardware with toradex kernel from Apalis_T30_LinuxImageV2.6. It`s just became invisible after kernel update to kernel 4.6.2.
