From 69fd2d3b0559f221a45e9a86b8ead16490f4e47b Mon Sep 17 00:00:00 2001 From: Andrew Sharp Date: Wed, 29 Aug 2012 14:16:32 +0000 Subject: [PATCH] pci: add CONFIG_PCI_ENUM_ONLY for platforms that don't need PCI setup done Introduce CONFIG_PCI_ENUM_ONLY variable for platforms that just want a quick enumberation of the PCI devices, but don't need any setup work done. This is very beneficial on platforms that have u-boot loaded by another boot loader which does a more sophisticated job of setup of PCI devices than u-boot. That way, u-boot can just read what's there and get on with life. This is what SeaBIOS does. Signed-off-by: Andrew Sharp --- README | 7 +++++++ drivers/pci/pci_auto.c | 35 +++++++++++++++++++++++++---------- 2 files changed, 32 insertions(+), 10 deletions(-) diff --git a/README b/README index da4341f4d6..d45eba77d3 100644 --- a/README +++ b/README @@ -3377,6 +3377,13 @@ Low Level (hardware related) configuration options: Disable PCI-Express on systems where it is supported but not required. +- CONFIG_PCI_ENUM_ONLY + Only scan through and get the devices on the busses. + Don't do any setup work, presumably because someone or + something has already done it, and we don't need to do it + a second time. Useful for platforms that are pre-booted + by coreboot or similar. + - CONFIG_SYS_SRIO: Chip has SRIO or not diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c index 9a42ede56b..ae61e24907 100644 --- a/drivers/pci/pci_auto.c +++ b/drivers/pci/pci_auto.c @@ -90,12 +90,14 @@ void pciauto_setup_device(struct pci_controller *hose, struct pci_region *io) { pci_addr_t bar_response; - pci_addr_t bar_value; pci_size_t bar_size; u16 cmdstat = 0; - struct pci_region *bar_res; int bar, bar_nr = 0; +#ifndef CONFIG_PCI_ENUM_ONLY + pci_addr_t bar_value; + struct pci_region *bar_res; int found_mem64 = 0; +#endif pci_hose_read_config_word(hose, dev, PCI_COMMAND, &cmdstat); cmdstat = (cmdstat & ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) | PCI_COMMAND_MASTER; @@ -103,20 +105,26 @@ void pciauto_setup_device(struct pci_controller *hose, for (bar = PCI_BASE_ADDRESS_0; bar < PCI_BASE_ADDRESS_0 + (bars_num * 4); bar += 4) { /* Tickle the BAR and get the response */ +#ifndef CONFIG_PCI_ENUM_ONLY pci_hose_write_config_dword(hose, dev, bar, 0xffffffff); +#endif pci_hose_read_config_dword(hose, dev, bar, &bar_response); /* If BAR is not implemented go to the next BAR */ if (!bar_response) continue; +#ifndef CONFIG_PCI_ENUM_ONLY found_mem64 = 0; +#endif /* Check the BAR type and set our address mask */ if (bar_response & PCI_BASE_ADDRESS_SPACE) { bar_size = ((~(bar_response & PCI_BASE_ADDRESS_IO_MASK)) & 0xffff) + 1; +#ifndef CONFIG_PCI_ENUM_ONLY bar_res = io; +#endif DEBUGF("PCI Autoconfig: BAR %d, I/O, size=0x%llx, ", bar_nr, (u64)bar_size); } else { @@ -124,26 +132,34 @@ void pciauto_setup_device(struct pci_controller *hose, PCI_BASE_ADDRESS_MEM_TYPE_64) { u32 bar_response_upper; u64 bar64; + +#ifndef CONFIG_PCI_ENUM_ONLY pci_hose_write_config_dword(hose, dev, bar + 4, 0xffffffff); +#endif pci_hose_read_config_dword(hose, dev, bar + 4, &bar_response_upper); bar64 = ((u64)bar_response_upper << 32) | bar_response; bar_size = ~(bar64 & PCI_BASE_ADDRESS_MEM_MASK) + 1; +#ifndef CONFIG_PCI_ENUM_ONLY found_mem64 = 1; +#endif } else { bar_size = (u32)(~(bar_response & PCI_BASE_ADDRESS_MEM_MASK) + 1); } +#ifndef CONFIG_PCI_ENUM_ONLY if (prefetch && (bar_response & PCI_BASE_ADDRESS_MEM_PREFETCH)) bar_res = prefetch; else bar_res = mem; +#endif DEBUGF("PCI Autoconfig: BAR %d, Mem, size=0x%llx, ", bar_nr, (u64)bar_size); } +#ifndef CONFIG_PCI_ENUM_ONLY if (pciauto_region_allocate(bar_res, bar_size, &bar_value) == 0) { /* Write it out and update our limit */ pci_hose_write_config_dword(hose, dev, bar, (u32)bar_value); @@ -162,9 +178,10 @@ void pciauto_setup_device(struct pci_controller *hose, #endif } - cmdstat |= (bar_response & PCI_BASE_ADDRESS_SPACE) ? - PCI_COMMAND_IO : PCI_COMMAND_MEMORY; } +#endif + cmdstat |= (bar_response & PCI_BASE_ADDRESS_SPACE) ? + PCI_COMMAND_IO : PCI_COMMAND_MEMORY; DEBUGF("\n"); @@ -357,12 +374,6 @@ int pciauto_config_device(struct pci_controller *hose, pci_dev_t dev) pci_hose_read_config_word(hose, dev, PCI_CLASS_DEVICE, &class); switch (class) { - case PCI_CLASS_PROCESSOR_POWERPC: /* an agent or end-point */ - DEBUGF("PCI AutoConfig: Found PowerPC device\n"); - pciauto_setup_device(hose, dev, 6, hose->pci_mem, - hose->pci_prefetch, hose->pci_io); - break; - case PCI_CLASS_BRIDGE_PCI: hose->current_busno++; pciauto_setup_device(hose, dev, 2, hose->pci_mem, @@ -429,6 +440,10 @@ int pciauto_config_device(struct pci_controller *hose, pci_dev_t dev) hose->pci_prefetch, hose->pci_io); break; #endif + + case PCI_CLASS_PROCESSOR_POWERPC: /* an agent or end-point */ + DEBUGF("PCI AutoConfig: Found PowerPC device\n"); + default: pciauto_setup_device(hose, dev, 6, hose->pci_mem, hose->pci_prefetch, hose->pci_io); -- 2.25.1