Re: [RFC PATCH] PCI/pci-host-generic: Add support for Cavium Thunder fixed BARs.
From: David Daney
Date: Wed Nov 25 2015 - 12:26:24 EST
On 11/25/2015 09:06 AM, Bjorn Helgaas wrote:
Hi David,
On Mon, Sep 28, 2015 at 05:56:24PM -0700, David Daney wrote:
From: David Daney <david.daney@xxxxxxxxxx>
Early versions of the Cavium Thunder CN88XX processor are missing
Enhanced Allocation (EA) capabilities for the fixed BAR addresses used
by the on-SoC hardware blocks.
Add config access functions that synthesize the missing EA
capabilities for versions that are missing that information. Since
this is a little hacky, gate the inclusion of the code with a new
Kconfig variable.
Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
What about this one? Do we still need it?
Yes, we still need this. However ...
This version looks like it
still has some debug code and it feels like a lot of hard-coding of
config offsets;
... I have a new version that removes the debugging code, and adds a
couple of corrections.
it'd be nice if it could be more table-driven.
There is and will only ever be a single silicon revision where this code
would be needed. So, I think the hard coding is the easiest solution,
and not really any worse than a table driver infrastructure.
I will send a new version of the patch.
Thanks for looking at this.
David
But
maybe this isn't needed anymore anyway.
Bjorn
---
As suggested by Bjorn Helgaas... It is RFC at this point, but this is
working well for me.
Depends on:
https://lkml.org/lkml/2015/9/28/796
drivers/pci/host/Kconfig | 9 +
drivers/pci/host/Makefile | 1 +
drivers/pci/host/pci-host-generic.c | 22 ++-
drivers/pci/host/thunder_ecam_config_io.c | 273 ++++++++++++++++++++++++++++++
4 files changed, 304 insertions(+), 1 deletion(-)
create mode 100644 drivers/pci/host/thunder_ecam_config_io.c
diff --git a/drivers/pci/host/Kconfig b/drivers/pci/host/Kconfig
index d5e58ba..9f3a9cd 100644
--- a/drivers/pci/host/Kconfig
+++ b/drivers/pci/host/Kconfig
@@ -58,6 +58,15 @@ config PCI_HOST_GENERIC
Say Y here if you want to support a simple generic PCI host
controller, such as the one emulated by kvmtool.
+config PCI_HOST_THUNDER
+ bool "Extensions to Generic PCI host controller for Cavium Thunder"
+ depends on PCI_HOST_GENERIC && ARM64
+ help
+ Say Y here to enable PCI config access methods needed by
+ CN88XX Cavium Thunder SoCs. The access is standard ECAM,
+ but Enhanced Allocation (EA) capability structures are
+ synthesized for on-SoC devices with fixed BARs.
+
config PCIE_SPEAR13XX
bool "STMicroelectronics SPEAr PCIe controller"
depends on ARCH_SPEAR13XX
diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
index 140d66f..8b77d62 100644
--- a/drivers/pci/host/Makefile
+++ b/drivers/pci/host/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o
obj-$(CONFIG_PCI_RCAR_GEN2) += pci-rcar-gen2.o
obj-$(CONFIG_PCI_RCAR_GEN2_PCIE) += pcie-rcar.o
obj-$(CONFIG_PCI_HOST_GENERIC) += pci-host-generic.o
+obj-$(CONFIG_PCI_HOST_THUNDER) += thunder_ecam_config_io.o
obj-$(CONFIG_PCIE_SPEAR13XX) += pcie-spear13xx.o
obj-$(CONFIG_PCI_KEYSTONE) += pci-keystone-dw.o pci-keystone.o
obj-$(CONFIG_PCIE_XILINX) += pcie-xilinx.o
diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
index 6f12830..64558e5 100644
--- a/drivers/pci/host/pci-host-generic.c
+++ b/drivers/pci/host/pci-host-generic.c
@@ -91,6 +91,21 @@ static struct gen_pci_cfg_bus_ops gen_pci_cfg_ecam_bus_ops = {
}
};
+#ifdef CONFIG_PCI_HOST_THUNDER
+int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val);
+int thunder_ecam_config_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val);
+static struct gen_pci_cfg_bus_ops gen_pci_cfg_thunder_ecam_bus_ops = {
+ .bus_shift = 20,
+ .ops = {
+ .map_bus = gen_pci_map_cfg_bus_ecam,
+ .read = thunder_ecam_config_read,
+ .write = thunder_ecam_config_write,
+ }
+};
+#endif
+
static void __iomem *gen_pci_map_cfg_bus_thunder_pem(struct pci_bus *bus,
unsigned int devfn,
int where)
@@ -108,6 +123,7 @@ static void __iomem *gen_pci_map_cfg_bus_thunder_pem(struct pci_bus *bus,
return pci->cfg.win[idx] + ((devfn << 16) | where);
}
+#ifdef CONFIG_PCI_HOST_THUNDER
static struct gen_pci_cfg_bus_ops gen_pci_cfg_thunder_pem_bus_ops = {
.bus_shift = 24,
.ops = {
@@ -116,6 +132,7 @@ static struct gen_pci_cfg_bus_ops gen_pci_cfg_thunder_pem_bus_ops = {
.write = pci_generic_config_write,
}
};
+#endif
static const struct of_device_id gen_pci_of_match[] = {
{ .compatible = "pci-host-cam-generic",
@@ -126,7 +143,10 @@ static const struct of_device_id gen_pci_of_match[] = {
{ .compatible = "cavium,pci-host-thunder-pem",
.data = &gen_pci_cfg_thunder_pem_bus_ops },
-
+#ifdef CONFIG_PCI_HOST_THUNDER
+ { .compatible = "cavium,pci-host-thunder-ecam",
+ .data = &gen_pci_cfg_thunder_ecam_bus_ops },
+#endif
{ },
};
MODULE_DEVICE_TABLE(of, gen_pci_of_match);
diff --git a/drivers/pci/host/thunder_ecam_config_io.c b/drivers/pci/host/thunder_ecam_config_io.c
new file mode 100644
index 0000000..58c3109
--- /dev/null
+++ b/drivers/pci/host/thunder_ecam_config_io.c
@@ -0,0 +1,273 @@
+/*
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2015 Cavium, Inc.
+ *
+ */
+
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/printk.h>
+
+static void set_val(u32 v, int where, int size, u32 *val)
+{
+ int shift = (where & 3) * 8;
+
+ pr_debug("set_val %04x: %08x\n", (unsigned)(where & ~3), v);
+ v >>= shift;
+ if (size == 1)
+ v &= 0xff;
+ else if (size == 2)
+ v &= 0xffff;
+ *val = v;
+}
+
+static int handle_ea_bar(u32 e0, int bar, struct pci_bus *bus,
+ unsigned int devfn, int where, int size, u32 *val)
+{
+ void __iomem *addr;
+ u32 v;
+ /*
+ * Each entry is 16-byte aligned bits[2,3] select which word
+ * in the entry
+ */
+ int where_a = where & 0xc;
+
+ if (where_a == 0) {
+ set_val(e0, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0x4) {
+ addr = bus->ops->map_bus(bus, devfn, bar); /* BAR 0 */
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ v = readl(addr);
+ v &= ~0xf;
+ v |= 2; /* EA entry-1. Base-L */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0x8) {
+ u32 barl_orig;
+ u32 barl_rb;
+
+ addr = bus->ops->map_bus(bus, devfn, bar); /* BAR 0 */
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ barl_orig = readl(addr + 0);
+ writel(0xffffffff, addr + 0);
+ barl_rb = readl(addr + 0);
+ writel(barl_orig, addr + 0);
+ /* zeros in unsettable bits. */
+ v = ~barl_rb & ~3;
+ v |= 0xc; /* EA entry-2. Offset-L */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xc) {
+ addr = bus->ops->map_bus(bus, devfn, bar + 4); /* BAR 1 */
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ v = readl(addr); /* EA entry-3. Base-H */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ return PCIBIOS_DEVICE_NOT_FOUND;
+}
+int thunder_ecam_config_write(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 val)
+{
+ /*
+ * All BARs have fixed addresses, ignore BAR writes so they
+ * don't get corrupted.
+ */
+ if ((where >= 0x10 && where < 0x2c) || (where >= 0x1a4 && where < 0x1bc))
+ /* BAR or SRIOV BAR */
+ return PCIBIOS_SUCCESSFUL;
+
+ return pci_generic_config_write(bus, devfn, where, size, val);
+}
+
+int thunder_ecam_config_read(struct pci_bus *bus, unsigned int devfn,
+ int where, int size, u32 *val)
+{
+ u32 v;
+ u32 vendor_device;
+ void __iomem *addr;
+ int cfg_type;
+ int where_a = where & ~3;
+
+ /*
+ * All BARs have fixed addresses specified by the EA
+ * capability, they must return zero on read.
+ */
+ if ((where >= 0x10 && where < 0x2c) || (where >= 0x1a4 && where < 0x1bc)) {
+ /* BAR or SRIOV BAR */
+ *val = 0;
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ addr = bus->ops->map_bus(bus, devfn, 0);
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
+ vendor_device = readl(addr);
+ if (vendor_device == 0xffffffff)
+ goto no_emulation;
+
+ addr = bus->ops->map_bus(bus, devfn, 8);
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
+ v = readl(addr);
+ if (v == 0xffffffff)
+ goto no_emulation;
+
+ if ((v & 0xff) < 8) {
+ pr_debug("%04x:%04x - Fix pass#: %08x, where: %03x, devfn: %03x\n",
+ vendor_device & 0xffff, vendor_device >> 16, v, (unsigned) where, devfn);
+ /* pass 1.x*/
+ } else {
+ pr_debug("%04x:%04x - OK pass#: %08x, devfn: %03x\n",
+ vendor_device & 0xffff, vendor_device >> 16, v, devfn);
+ goto no_emulation;
+ }
+
+ addr = bus->ops->map_bus(bus, devfn, 0xc);
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+
+ v = readl(addr);
+ /* Check for non type-00 header. */
+ cfg_type = (v >> 16) & 0x7f;
+ if (cfg_type == 0) {
+ bool has_msix;
+ bool is_nic = (vendor_device == 0xa01e177d);
+ bool is_tns = (vendor_device == 0xa01f177d);
+
+ addr = bus->ops->map_bus(bus, devfn, 0x70);
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ /* E_CAP */
+ v = readl(addr);
+ has_msix = (v & 0xff00) != 0;
+
+ if (!has_msix && where_a == 0x70) {
+ v |= 0xbc00; /* next capability is EA at 0xbc */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xb0) {
+ addr = bus->ops->map_bus(bus, devfn, where_a);
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ v = readl(addr);
+ if (v & 0xff00)
+ pr_err("Bad MSIX cap header: %08x\n", v);
+ v |= 0xbc00; /* next capability is EA at 0xbc */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xbc) {
+ if (is_nic)
+ v = 0x40014; /* EA last in chain, 4 entries. */
+ else if (is_tns)
+ v = 0x40014; /* EA last in chain, 3 entries. */
+ else if (has_msix)
+ v = 0x20014; /* EA last in chain, 2 entries. */
+ else
+ v = 0x10014; /* EA last in chain, 1 entry. */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a >= 0xc0 && where_a < 0xd0)
+ return handle_ea_bar(0x80ff0003, /* EA entry-0. PP=0, BAR0 Size:3 */
+ 0x10, bus, devfn, where, size, val);
+ if (where_a >= 0xd0 && where_a < 0xe0 && has_msix)
+ return handle_ea_bar(0x80ff0043, /* EA entry-1. PP=0, BAR4 Size:3 */
+ 0x20, bus, devfn, where, size, val);
+ if (where_a >= 0xe0 && where_a < 0xf0 && is_tns)
+ return handle_ea_bar(0x80ff0023, /* EA entry-2. PP=0, BAR2, Size:3 */
+ 0x18, bus, devfn, where, size, val);
+ if (where_a >= 0xe0 && where_a < 0xf0 && is_nic)
+ return handle_ea_bar(0x80ff0493, /* EA entry-2. PP=4, VF_BAR0 (9), Size:3 */
+ 0x1a4, bus, devfn, where, size, val);
+ if (where_a >= 0xf0 && where_a < 0x100 && is_nic)
+ return handle_ea_bar(0x80ff04d3, /* EA entry-3. PP=4, VF_BAR4 (d), Size:3 */
+ 0x1b4, bus, devfn, where, size, val);
+ } else if (cfg_type == 1) {
+ if (where_a == 0x70) {
+ addr = bus->ops->map_bus(bus, devfn, where_a);
+ if (!addr) {
+ *val = ~0;
+ return PCIBIOS_DEVICE_NOT_FOUND;
+ }
+ v = readl(addr);
+ if (v & 0xff00)
+ pr_err("Bad PCIe cap header: %08x\n", v);
+ v |= 0xbc00; /* next capability is EA at 0xbc */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xbc) {
+ v = 0x10014; /* EA last in chain, 1 entry. */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xc0) {
+ v = 0x0101; /* subordinate:secondary = 1:1 */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xc4) {
+ v = 0x80ff0564; /* Enabled, not-Write, SP=ff, PP=05, BEI=6, ES=4 */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xc8) {
+ v = 0x00000002; /* Base-L 64-bit */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xcc) {
+ v = 0xfffffffe; /* MaxOffset-L 64-bit */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xd0) {
+ if (devfn == 8)
+ v = 0x000087e0; /* RSL Base-H */
+ else
+ v = 0x00008430; /* NIC Base-H */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+ if (where_a == 0xd4) {
+ v = 0x0000000f; /* MaxOffset-H */
+ set_val(v, where, size, val);
+ return PCIBIOS_SUCCESSFUL;
+ }
+
+ }
+no_emulation:
+ return pci_generic_config_read(bus, devfn, where, size, val);
+}
--
1.9.1
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