[PATCH v2 2/2] PCI: designware: use iATU0 for cfg and IO, iATU1 for MEM

From: Jisheng Zhang
Date: Thu Apr 30 2015 - 04:26:52 EST


Most transactions' type are cfg0 and MEM, so the Current iATU usage is not
balanced, iATU0 is hot while iATU1 is rarely used. This patch refactors
the iATU usage: iATU0 for cfg and IO, iATU1 for MEM. This allocation
ideas comes from Minghuan Lian <Minghuan.Lian@xxxxxxxxxxxxx>:

http://www.spinics.net/lists/linux-pci/msg40440.html

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
---
drivers/pci/host/pcie-designware.c | 81 +++++++++++++++++++++-----------------
1 file changed, 45 insertions(+), 36 deletions(-)

diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 1da1446..40a0db1 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -508,6 +508,11 @@ int dw_pcie_host_init(struct pcie_port *pp)
if (pp->ops->host_init)
pp->ops->host_init(pp);

+ if (!pp->ops->rd_other_conf)
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
+ PCIE_ATU_TYPE_MEM, pp->mem_mod_base,
+ pp->mem_bus_addr, pp->mem_size);
+
dw_pcie_wr_own_conf(pp, PCI_BASE_ADDRESS_0, 4, 0);

/* program correct class for RC */
@@ -533,66 +538,70 @@ int dw_pcie_host_init(struct pcie_port *pp)
static int dw_pcie_rd_other_conf(struct pcie_port *pp, struct pci_bus *bus,
u32 devfn, int where, int size, u32 *val)
{
- int ret = PCIBIOS_SUCCESSFUL;
- u32 address, busdev;
+ int ret, type;
+ u32 address, busdev, cfg_size;
+ u64 cpu_addr;
+ void __iomem *va_cfg_base;

busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
PCIE_ATU_FUNC(PCI_FUNC(devfn));
address = where & ~0x3;

if (bus->parent->number == pp->root_bus_nr) {
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
- PCIE_ATU_TYPE_CFG0, pp->cfg0_mod_base,
- busdev, pp->cfg0_size);
- ret = dw_pcie_cfg_read(pp->va_cfg0_base + address, where, size,
- val);
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
- PCIE_ATU_TYPE_MEM, pp->mem_mod_base,
- pp->mem_bus_addr, pp->mem_size);
+ type = PCIE_ATU_TYPE_CFG0;
+ cpu_addr = pp->cfg0_mod_base;
+ cfg_size = pp->cfg0_size;
+ va_cfg_base = pp->va_cfg0_base;
} else {
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
- PCIE_ATU_TYPE_CFG1, pp->cfg1_mod_base,
- busdev, pp->cfg1_size);
- ret = dw_pcie_cfg_read(pp->va_cfg1_base + address, where, size,
- val);
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
- PCIE_ATU_TYPE_IO, pp->io_mod_base,
- pp->io_bus_addr, pp->io_size);
+ type = PCIE_ATU_TYPE_CFG1;
+ cpu_addr = pp->cfg1_mod_base;
+ cfg_size = pp->cfg1_size;
+ va_cfg_base = pp->va_cfg1_base;
}

+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ type, cpu_addr,
+ busdev, cfg_size);
+ ret = dw_pcie_cfg_read(va_cfg_base + address, where, size, val);
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ PCIE_ATU_TYPE_IO, pp->io_mod_base,
+ pp->io_bus_addr, pp->io_size);
+
return ret;
}

static int dw_pcie_wr_other_conf(struct pcie_port *pp, struct pci_bus *bus,
u32 devfn, int where, int size, u32 val)
{
- int ret = PCIBIOS_SUCCESSFUL;
- u32 address, busdev;
+ int ret, type;
+ u32 address, busdev, cfg_size;
+ u64 cpu_addr;
+ void __iomem *va_cfg_base;

busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
PCIE_ATU_FUNC(PCI_FUNC(devfn));
address = where & ~0x3;

if (bus->parent->number == pp->root_bus_nr) {
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
- PCIE_ATU_TYPE_CFG0, pp->cfg0_mod_base,
- busdev, pp->cfg0_size);
- ret = dw_pcie_cfg_write(pp->va_cfg0_base + address, where, size,
- val);
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
- PCIE_ATU_TYPE_MEM, pp->mem_mod_base,
- pp->mem_bus_addr, pp->mem_size);
+ type = PCIE_ATU_TYPE_CFG0;
+ cpu_addr = pp->cfg0_mod_base;
+ cfg_size = pp->cfg0_size;
+ va_cfg_base = pp->va_cfg0_base;
} else {
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
- PCIE_ATU_TYPE_CFG1, pp->cfg1_mod_base,
- busdev, pp->cfg1_size);
- ret = dw_pcie_cfg_write(pp->va_cfg1_base + address, where, size,
- val);
- dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX1,
- PCIE_ATU_TYPE_IO, pp->io_mod_base,
- pp->io_bus_addr, pp->io_size);
+ type = PCIE_ATU_TYPE_CFG1;
+ cpu_addr = pp->cfg1_mod_base;
+ cfg_size = pp->cfg1_size;
+ va_cfg_base = pp->va_cfg1_base;
}

+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ type, cpu_addr,
+ busdev, cfg_size);
+ ret = dw_pcie_cfg_write(va_cfg_base + address, where, size, val);
+ dw_pcie_prog_outbound_atu(pp, PCIE_ATU_REGION_INDEX0,
+ PCIE_ATU_TYPE_IO, pp->io_mod_base,
+ pp->io_bus_addr, pp->io_size);
+
return ret;
}

--
2.1.4

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