From e6e5ecb7e813fa151c558c739d5394dce0a2af8e Mon Sep 17 00:00:00 2001 From: Arthur Heymans Date: Thu, 20 Dec 2018 01:44:50 +0100 Subject: sb/intel/i82801gx: Implement PCIe coalescing The implementation is a simplified version of the haswell/broadwell code. This also adds a chip option to enable coalescing from the devicetree. Change-Id: I6d7ddef96e4f45e163f7017175398a0938a18273 Signed-off-by: Arthur Heymans Reviewed-on: https://review.coreboot.org/c/30320 Tested-by: build bot (Jenkins) Reviewed-by: Nico Huber --- src/southbridge/intel/i82801gx/chip.h | 3 + src/southbridge/intel/i82801gx/i82801gx.h | 3 + src/southbridge/intel/i82801gx/pcie.c | 164 ++++++++++++++++++++++++++++++ 3 files changed, 170 insertions(+) (limited to 'src/southbridge') diff --git a/src/southbridge/intel/i82801gx/chip.h b/src/southbridge/intel/i82801gx/chip.h index 3a20ab1cb3..db27ef7097 100644 --- a/src/southbridge/intel/i82801gx/chip.h +++ b/src/southbridge/intel/i82801gx/chip.h @@ -68,6 +68,9 @@ struct southbridge_intel_i82801gx_config { uint32_t sata_ahci; uint32_t sata_ports_implemented; + /* Enable linear PCIe Root Port function numbers starting at zero */ + uint8_t pcie_port_coalesce; + int c4onc3_enable:1; int docking_supported:1; int p_cnt_throttling_supported:1; diff --git a/src/southbridge/intel/i82801gx/i82801gx.h b/src/southbridge/intel/i82801gx/i82801gx.h index 395cdd13cf..e664eb43fa 100644 --- a/src/southbridge/intel/i82801gx/i82801gx.h +++ b/src/southbridge/intel/i82801gx/i82801gx.h @@ -84,6 +84,9 @@ int southbridge_detect_s3_resume(void); #define GPI_IS_SCI 0x02 #define GPI_IS_NMI 0x03 +#define FDVCT 0xe4 +#define PCIE_4_PORTS_MAX (1 << 7) + /* GEN_PMCON_3 bits */ #define RTC_BATTERY_DEAD (1 << 2) #define RTC_POWER_FAILED (1 << 1) diff --git a/src/southbridge/intel/i82801gx/pcie.c b/src/southbridge/intel/i82801gx/pcie.c index 7de98908bf..c0f9c1239c 100644 --- a/src/southbridge/intel/i82801gx/pcie.c +++ b/src/southbridge/intel/i82801gx/pcie.c @@ -18,6 +18,36 @@ #include #include #include +#include "i82801gx.h" + +/* Low Power variant has 6 root ports. */ +#define NUM_ROOT_PORTS 6 + +struct root_port_config { + /* RPFN is a write-once register so keep a copy until it is written */ + u32 orig_rpfn; + u32 new_rpfn; + int num_ports; + struct device *ports[NUM_ROOT_PORTS]; +}; + +static struct root_port_config rpc; + +static inline int root_port_is_first(struct device *dev) +{ + return PCI_FUNC(dev->path.pci.devfn) == 0; +} + +static inline int root_port_is_last(struct device *dev) +{ + return PCI_FUNC(dev->path.pci.devfn) == (rpc.num_ports - 1); +} + +/* Root ports are numbered 1..N in the documentation. */ +static inline int root_port_number(struct device *dev) +{ + return PCI_FUNC(dev->path.pci.devfn) + 1; +} static void pci_init(struct device *dev) { @@ -89,6 +119,139 @@ static void pci_init(struct device *dev) pci_write_config16(dev, 0x1e, reg16); } +static int get_num_ports(void) +{ + struct device *dev = pcidev_on_root(31, 0); + if (pci_read_config32(dev, FDVCT) & PCIE_4_PORTS_MAX) + return 4; + else + return 6; +} + +static void root_port_init_config(struct device *dev) +{ + int rp; + + if (root_port_is_first(dev)) { + rpc.orig_rpfn = RCBA32(RPFN); + rpc.new_rpfn = rpc.orig_rpfn; + rpc.num_ports = get_num_ports(); + } + + rp = root_port_number(dev); + if (rp > rpc.num_ports) { + printk(BIOS_ERR, "Found Root Port %d, expecting %d\n", + rp, rpc.num_ports); + return; + } + + /* Cache pci device. */ + rpc.ports[rp - 1] = dev; +} + +/* Update devicetree with new Root Port function number assignment */ +static void ich_pcie_device_set_func(int index, int pci_func) +{ + struct device *dev; + unsigned int new_devfn; + + dev = rpc.ports[index]; + + /* Set the new PCI function field for this Root Port. */ + rpc.new_rpfn &= ~RPFN_FNMASK(index); + rpc.new_rpfn |= RPFN_FNSET(index, pci_func); + + /* Determine the new devfn for this port */ + new_devfn = PCI_DEVFN(ICH_PCIE_DEV_SLOT, pci_func); + + if (dev->path.pci.devfn != new_devfn) { + printk(BIOS_DEBUG, + "ICH: PCIe map %02x.%1x -> %02x.%1x\n", + PCI_SLOT(dev->path.pci.devfn), + PCI_FUNC(dev->path.pci.devfn), + PCI_SLOT(new_devfn), PCI_FUNC(new_devfn)); + + dev->path.pci.devfn = new_devfn; + } +} + +static void root_port_commit_config(struct device *dev) +{ + int i; + int coalesce = 0; + + if (dev->chip_info != NULL) { + struct southbridge_intel_i82801gx_config *config + = dev->chip_info; + coalesce = config->pcie_port_coalesce; + } + + if (!rpc.ports[0]->enabled) + coalesce = 1; + + for (i = 0; i < rpc.num_ports; i++) { + struct device *pcie_dev; + + pcie_dev = rpc.ports[i]; + + if (dev == NULL) { + printk(BIOS_ERR, "Root Port %d device is NULL?\n", + i + 1); + continue; + } + + if (pcie_dev->enabled) + continue; + + printk(BIOS_DEBUG, "%s: Disabling device\n", + dev_path(pcie_dev)); + + /* Disable this device if possible */ + i82801gx_enable(pcie_dev); + } + + if (coalesce) { + int current_func; + + /* For all Root Ports N enabled ports get assigned the lower + * PCI function number. The disabled ones get upper PCI + * function numbers. */ + current_func = 0; + for (i = 0; i < rpc.num_ports; i++) { + if (!rpc.ports[i]->enabled) + continue; + ich_pcie_device_set_func(i, current_func); + current_func++; + } + + /* Allocate the disabled devices' PCI function number. */ + for (i = 0; i < rpc.num_ports; i++) { + if (rpc.ports[i]->enabled) + continue; + ich_pcie_device_set_func(i, current_func); + current_func++; + } + } + + printk(BIOS_SPEW, "ICH: RPFN 0x%08x -> 0x%08x\n", + rpc.orig_rpfn, rpc.new_rpfn); + RCBA32(RPFN) = rpc.new_rpfn; +} + +static void ich_pcie_enable(struct device *dev) +{ + /* Add this device to the root port config structure. */ + root_port_init_config(dev); + + /* + * When processing the last PCIe root port we can now + * update the Root Port Function Number and Hide register. + */ + if (root_port_is_last(dev)) + root_port_commit_config(dev); +} + + static void pcie_set_subsystem(struct device *dev, unsigned int vendor, unsigned int device) { @@ -111,6 +274,7 @@ static struct device_operations device_ops = { .set_resources = pci_dev_set_resources, .enable_resources = pci_bus_enable_resources, .init = pci_init, + .enable = ich_pcie_enable, .scan_bus = pci_scan_bridge, .ops_pci = &pci_ops, }; -- cgit v1.2.3