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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/powerpc/kernel/rtas_pci.c
Initial import
Diffstat (limited to 'arch/powerpc/kernel/rtas_pci.c')
-rw-r--r--arch/powerpc/kernel/rtas_pci.c279
1 files changed, 279 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/rtas_pci.c b/arch/powerpc/kernel/rtas_pci.c
new file mode 100644
index 000000000..73f193458
--- /dev/null
+++ b/arch/powerpc/kernel/rtas_pci.c
@@ -0,0 +1,279 @@
+/*
+ * Copyright (C) 2001 Dave Engebretsen, IBM Corporation
+ * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
+ *
+ * RTAS specific routines for PCI.
+ *
+ * Based on code from pci.c, chrp_pci.c and pSeries_pci.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/threads.h>
+#include <linux/pci.h>
+#include <linux/string.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/irq.h>
+#include <asm/prom.h>
+#include <asm/machdep.h>
+#include <asm/pci-bridge.h>
+#include <asm/iommu.h>
+#include <asm/rtas.h>
+#include <asm/mpic.h>
+#include <asm/ppc-pci.h>
+#include <asm/eeh.h>
+
+/* RTAS tokens */
+static int read_pci_config;
+static int write_pci_config;
+static int ibm_read_pci_config;
+static int ibm_write_pci_config;
+
+static inline int config_access_valid(struct pci_dn *dn, int where)
+{
+ if (where < 256)
+ return 1;
+ if (where < 4096 && dn->pci_ext_config_space)
+ return 1;
+
+ return 0;
+}
+
+int rtas_read_config(struct pci_dn *pdn, int where, int size, u32 *val)
+{
+ int returnval = -1;
+ unsigned long buid, addr;
+ int ret;
+
+ if (!pdn)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ if (!config_access_valid(pdn, where))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+#ifdef CONFIG_EEH
+ if (pdn->edev && pdn->edev->pe &&
+ (pdn->edev->pe->state & EEH_PE_CFG_BLOCKED))
+ return PCIBIOS_SET_FAILED;
+#endif
+
+ addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
+ buid = pdn->phb->buid;
+ if (buid) {
+ ret = rtas_call(ibm_read_pci_config, 4, 2, &returnval,
+ addr, BUID_HI(buid), BUID_LO(buid), size);
+ } else {
+ ret = rtas_call(read_pci_config, 2, 2, &returnval, addr, size);
+ }
+ *val = returnval;
+
+ if (ret)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int rtas_pci_read_config(struct pci_bus *bus,
+ unsigned int devfn,
+ int where, int size, u32 *val)
+{
+ struct device_node *busdn, *dn;
+ struct pci_dn *pdn;
+ bool found = false;
+ int ret;
+
+ /* Search only direct children of the bus */
+ *val = 0xFFFFFFFF;
+ busdn = pci_bus_to_OF_node(bus);
+ for (dn = busdn->child; dn; dn = dn->sibling) {
+ pdn = PCI_DN(dn);
+ if (pdn && pdn->devfn == devfn
+ && of_device_is_available(dn)) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ ret = rtas_read_config(pdn, where, size, val);
+ if (*val == EEH_IO_ERROR_VALUE(size) &&
+ eeh_dev_check_failure(pdn_to_eeh_dev(pdn)))
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return ret;
+}
+
+int rtas_write_config(struct pci_dn *pdn, int where, int size, u32 val)
+{
+ unsigned long buid, addr;
+ int ret;
+
+ if (!pdn)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ if (!config_access_valid(pdn, where))
+ return PCIBIOS_BAD_REGISTER_NUMBER;
+#ifdef CONFIG_EEH
+ if (pdn->edev && pdn->edev->pe &&
+ (pdn->edev->pe->state & EEH_PE_CFG_BLOCKED))
+ return PCIBIOS_SET_FAILED;
+#endif
+
+ addr = rtas_config_addr(pdn->busno, pdn->devfn, where);
+ buid = pdn->phb->buid;
+ if (buid) {
+ ret = rtas_call(ibm_write_pci_config, 5, 1, NULL, addr,
+ BUID_HI(buid), BUID_LO(buid), size, (ulong) val);
+ } else {
+ ret = rtas_call(write_pci_config, 3, 1, NULL, addr, size, (ulong)val);
+ }
+
+ if (ret)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return PCIBIOS_SUCCESSFUL;
+}
+
+static int rtas_pci_write_config(struct pci_bus *bus,
+ unsigned int devfn,
+ int where, int size, u32 val)
+{
+ struct device_node *busdn, *dn;
+ struct pci_dn *pdn;
+ bool found = false;
+
+ /* Search only direct children of the bus */
+ busdn = pci_bus_to_OF_node(bus);
+ for (dn = busdn->child; dn; dn = dn->sibling) {
+ pdn = PCI_DN(dn);
+ if (pdn && pdn->devfn == devfn
+ && of_device_is_available(dn)) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ return PCIBIOS_DEVICE_NOT_FOUND;
+
+ return rtas_write_config(pdn, where, size, val);
+}
+
+static struct pci_ops rtas_pci_ops = {
+ .read = rtas_pci_read_config,
+ .write = rtas_pci_write_config,
+};
+
+static int is_python(struct device_node *dev)
+{
+ const char *model = of_get_property(dev, "model", NULL);
+
+ if (model && strstr(model, "Python"))
+ return 1;
+
+ return 0;
+}
+
+static void python_countermeasures(struct device_node *dev)
+{
+ struct resource registers;
+ void __iomem *chip_regs;
+ volatile u32 val;
+
+ if (of_address_to_resource(dev, 0, &registers)) {
+ printk(KERN_ERR "Can't get address for Python workarounds !\n");
+ return;
+ }
+
+ /* Python's register file is 1 MB in size. */
+ chip_regs = ioremap(registers.start & ~(0xfffffUL), 0x100000);
+
+ /*
+ * Firmware doesn't always clear this bit which is critical
+ * for good performance - Anton
+ */
+
+#define PRG_CL_RESET_VALID 0x00010000
+
+ val = in_be32(chip_regs + 0xf6030);
+ if (val & PRG_CL_RESET_VALID) {
+ printk(KERN_INFO "Python workaround: ");
+ val &= ~PRG_CL_RESET_VALID;
+ out_be32(chip_regs + 0xf6030, val);
+ /*
+ * We must read it back for changes to
+ * take effect
+ */
+ val = in_be32(chip_regs + 0xf6030);
+ printk("reg0: %x\n", val);
+ }
+
+ iounmap(chip_regs);
+}
+
+void __init init_pci_config_tokens(void)
+{
+ read_pci_config = rtas_token("read-pci-config");
+ write_pci_config = rtas_token("write-pci-config");
+ ibm_read_pci_config = rtas_token("ibm,read-pci-config");
+ ibm_write_pci_config = rtas_token("ibm,write-pci-config");
+}
+
+unsigned long get_phb_buid(struct device_node *phb)
+{
+ struct resource r;
+
+ if (ibm_read_pci_config == -1)
+ return 0;
+ if (of_address_to_resource(phb, 0, &r))
+ return 0;
+ return r.start;
+}
+
+static int phb_set_bus_ranges(struct device_node *dev,
+ struct pci_controller *phb)
+{
+ const __be32 *bus_range;
+ unsigned int len;
+
+ bus_range = of_get_property(dev, "bus-range", &len);
+ if (bus_range == NULL || len < 2 * sizeof(int)) {
+ return 1;
+ }
+
+ phb->first_busno = be32_to_cpu(bus_range[0]);
+ phb->last_busno = be32_to_cpu(bus_range[1]);
+
+ return 0;
+}
+
+int rtas_setup_phb(struct pci_controller *phb)
+{
+ struct device_node *dev = phb->dn;
+
+ if (is_python(dev))
+ python_countermeasures(dev);
+
+ if (phb_set_bus_ranges(dev, phb))
+ return 1;
+
+ phb->ops = &rtas_pci_ops;
+ phb->buid = get_phb_buid(dev);
+
+ return 0;
+}