[PATCH v2 08/22] PCI: dwc: designware: Add EP mode support

From: Kishon Vijay Abraham I
Date: Fri Feb 17 2017 - 04:54:37 EST


Add endpoint mode support to designware driver. This uses the
EP Core layer introduced recently to add endpoint mode support.
*Any* function driver can now use this designware device
in order to achieve the EP functionality.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
drivers/pci/dwc/Kconfig | 5 +
drivers/pci/dwc/Makefile | 1 +
drivers/pci/dwc/pcie-designware-ep.c | 342 ++++++++++++++++++++++++++++++++++
drivers/pci/dwc/pcie-designware.c | 51 +++++
drivers/pci/dwc/pcie-designware.h | 72 +++++++
5 files changed, 471 insertions(+)
create mode 100644 drivers/pci/dwc/pcie-designware-ep.c

diff --git a/drivers/pci/dwc/Kconfig b/drivers/pci/dwc/Kconfig
index dfb8a69..00335c7 100644
--- a/drivers/pci/dwc/Kconfig
+++ b/drivers/pci/dwc/Kconfig
@@ -9,6 +9,11 @@ config PCIE_DW_HOST
depends on PCI_MSI_IRQ_DOMAIN
select PCIE_DW

+config PCIE_DW_EP
+ bool
+ depends on PCI_ENDPOINT
+ select PCIE_DW
+
config PCI_DRA7XX
bool "TI DRA7xx PCIe controller"
depends on PCI
diff --git a/drivers/pci/dwc/Makefile b/drivers/pci/dwc/Makefile
index a2df13c..b38425d 100644
--- a/drivers/pci/dwc/Makefile
+++ b/drivers/pci/dwc/Makefile
@@ -1,5 +1,6 @@
obj-$(CONFIG_PCIE_DW) += pcie-designware.o
obj-$(CONFIG_PCIE_DW_HOST) += pcie-designware-host.o
+obj-$(CONFIG_PCIE_DW_EP) += pcie-designware-ep.o
obj-$(CONFIG_PCIE_DW_PLAT) += pcie-designware-plat.o
obj-$(CONFIG_PCI_DRA7XX) += pci-dra7xx.o
obj-$(CONFIG_PCI_EXYNOS) += pci-exynos.o
diff --git a/drivers/pci/dwc/pcie-designware-ep.c b/drivers/pci/dwc/pcie-designware-ep.c
new file mode 100644
index 0000000..e465c5e
--- /dev/null
+++ b/drivers/pci/dwc/pcie-designware-ep.c
@@ -0,0 +1,342 @@
+/**
+ * Synopsys Designware PCIe Endpoint controller driver
+ *
+ * Copyright (C) 2017 Texas Instruments
+ * Author: Kishon Vijay Abraham I <kishon@xxxxxx>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 of
+ * the License as published by the Free Software Foundation.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/of.h>
+
+#include "pcie-designware.h"
+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+
+void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
+{
+ struct pci_epc *epc = ep->epc;
+ struct pci_epf *epf;
+
+ list_for_each_entry(epf, &epc->pci_epf, list)
+ pci_epf_linkup(epf);
+}
+
+static void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
+{
+ u32 reg;
+
+ reg = PCI_BASE_ADDRESS_0 + (4 * bar);
+ dw_pcie_write_dbi(pci, pci->dbi_base2, reg, 0x4, 0x0);
+ dw_pcie_write_dbi(pci, pci->dbi_base, reg, 0x4, 0x0);
+}
+
+static int dw_pcie_ep_write_header(struct pci_epc *epc,
+ struct pci_epf_header *hdr)
+{
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ void __iomem *base = pci->dbi_base;
+
+ dw_pcie_write_dbi(pci, base, PCI_VENDOR_ID, 0x2, hdr->vendorid);
+ dw_pcie_write_dbi(pci, base, PCI_DEVICE_ID, 0x2, hdr->deviceid);
+ dw_pcie_write_dbi(pci, base, PCI_REVISION_ID, 0x1, hdr->revid);
+ dw_pcie_write_dbi(pci, base, PCI_CLASS_PROG, 0x1, hdr->progif_code);
+ dw_pcie_write_dbi(pci, base, PCI_CLASS_DEVICE, 0x2,
+ hdr->subclass_code | hdr->baseclass_code << 8);
+ dw_pcie_write_dbi(pci, base, PCI_CACHE_LINE_SIZE, 0x1,
+ hdr->cache_line_size);
+ dw_pcie_write_dbi(pci, base, PCI_SUBSYSTEM_VENDOR_ID, 0x2,
+ hdr->subsys_vendor_id);
+ dw_pcie_write_dbi(pci, base, PCI_SUBSYSTEM_ID, 0x2, hdr->subsys_id);
+ dw_pcie_write_dbi(pci, base, PCI_INTERRUPT_PIN, 0x1,
+ hdr->interrupt_pin);
+
+ return 0;
+}
+
+static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, enum pci_barno bar,
+ dma_addr_t cpu_addr,
+ enum dw_pcie_as_type as_type)
+{
+ int ret;
+ u32 free_win;
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ free_win = find_first_zero_bit(&ep->ib_window_map,
+ sizeof(ep->ib_window_map));
+ if (free_win >= ep->num_ib_windows) {
+ dev_err(pci->dev, "no free inbound window\n");
+ return -EINVAL;
+ }
+
+ ret = dw_pcie_prog_inbound_atu(pci, free_win, bar, cpu_addr,
+ as_type);
+ if (ret < 0) {
+ dev_err(pci->dev, "Failed to program IB window\n");
+ return ret;
+ }
+
+ ep->bar_to_atu[bar] = free_win;
+ set_bit(free_win, &ep->ib_window_map);
+
+ return 0;
+}
+
+static int dw_pcie_ep_outbound_atu(struct dw_pcie_ep *ep, phys_addr_t phys_addr,
+ u64 pci_addr, size_t size)
+{
+ u32 free_win;
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ free_win = find_first_zero_bit(&ep->ob_window_map,
+ sizeof(ep->ob_window_map));
+ if (free_win >= ep->num_ob_windows) {
+ dev_err(pci->dev, "no free outbound window\n");
+ return -EINVAL;
+ }
+
+ dw_pcie_prog_outbound_atu(pci, free_win, PCIE_ATU_TYPE_MEM,
+ phys_addr, pci_addr, size);
+
+ set_bit(free_win, &ep->ob_window_map);
+ ep->outbound_addr[free_win] = phys_addr;
+
+ return 0;
+}
+
+static void dw_pcie_ep_clear_bar(struct pci_epc *epc, enum pci_barno bar)
+{
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ u32 atu_index = ep->bar_to_atu[bar];
+
+ dw_pcie_ep_reset_bar(pci, bar);
+
+ dw_pcie_disable_atu(pci, atu_index, DW_PCIE_REGION_INBOUND);
+ clear_bit(atu_index, &ep->ib_window_map);
+}
+
+static int dw_pcie_ep_set_bar(struct pci_epc *epc, enum pci_barno bar,
+ dma_addr_t bar_phys, size_t size, int flags)
+{
+ int ret;
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ enum dw_pcie_as_type as_type;
+ u32 reg = PCI_BASE_ADDRESS_0 + (4 * bar);
+
+ if (!(flags & PCI_BASE_ADDRESS_SPACE))
+ as_type = DW_PCIE_AS_MEM;
+ else
+ as_type = DW_PCIE_AS_IO;
+
+ ret = dw_pcie_ep_inbound_atu(ep, bar, bar_phys, as_type);
+ if (ret)
+ return ret;
+
+ dw_pcie_write_dbi(pci, pci->dbi_base2, reg, 0x4, size - 1);
+ dw_pcie_write_dbi(pci, pci->dbi_base, reg, 0x4, flags);
+
+ return 0;
+}
+
+static int dw_pcie_find_index(struct dw_pcie_ep *ep, phys_addr_t addr,
+ u32 *atu_index)
+{
+ u32 index;
+
+ for (index = 0; index < ep->num_ob_windows; index++) {
+ if (ep->outbound_addr[index] != addr)
+ continue;
+ *atu_index = index;
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static void dw_pcie_ep_unmap_addr(struct pci_epc *epc, phys_addr_t addr)
+{
+ int ret;
+ u32 atu_index;
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ ret = dw_pcie_find_index(ep, addr, &atu_index);
+ if (ret < 0)
+ return;
+
+ dw_pcie_disable_atu(pci, atu_index, DW_PCIE_REGION_OUTBOUND);
+ clear_bit(atu_index, &ep->ob_window_map);
+}
+
+static int dw_pcie_ep_map_addr(struct pci_epc *epc, phys_addr_t addr,
+ u64 pci_addr, size_t size)
+{
+ int ret;
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ ret = dw_pcie_ep_outbound_atu(ep, addr, pci_addr, size);
+ if (ret) {
+ dev_err(pci->dev, "failed to enable address\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int dw_pcie_ep_get_msi(struct pci_epc *epc)
+{
+ int val;
+ u32 lower_addr;
+ u32 upper_addr;
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ val = dw_pcie_read_dbi(pci, pci->dbi_base, MSI_MESSAGE_CONTROL, 0x2);
+ val = (val & MSI_CAP_MME_MASK) >> MSI_CAP_MME_SHIFT;
+
+ lower_addr = dw_pcie_read_dbi(pci, pci->dbi_base, MSI_MESSAGE_ADDR_L32,
+ 0x4);
+ upper_addr = dw_pcie_read_dbi(pci, pci->dbi_base, MSI_MESSAGE_ADDR_U32,
+ 0x4);
+
+ if (!(lower_addr || upper_addr))
+ return -EINVAL;
+
+ return val;
+}
+
+static int dw_pcie_ep_set_msi(struct pci_epc *epc, u8 encode_int)
+{
+ int val;
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ val = (encode_int << MSI_CAP_MMC_SHIFT);
+ dw_pcie_write_dbi(pci, pci->dbi_base, MSI_MESSAGE_CONTROL, 0x2, val);
+
+ return 0;
+}
+
+static int dw_pcie_ep_raise_irq(struct pci_epc *epc,
+ enum pci_epc_irq_type type, u8 interrupt_num)
+{
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+
+ if (!ep->ops->raise_irq)
+ return -EINVAL;
+
+ return ep->ops->raise_irq(ep, type, interrupt_num);
+}
+
+static void dw_pcie_ep_stop(struct pci_epc *epc)
+{
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ if (!pci->ops->stop_link)
+ return;
+
+ pci->ops->stop_link(pci);
+}
+
+static int dw_pcie_ep_start(struct pci_epc *epc)
+{
+ struct dw_pcie_ep *ep = epc_get_drvdata(epc);
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+
+ if (!pci->ops->start_link)
+ return -EINVAL;
+
+ return pci->ops->start_link(pci);
+}
+
+static const struct pci_epc_ops epc_ops = {
+ .write_header = dw_pcie_ep_write_header,
+ .set_bar = dw_pcie_ep_set_bar,
+ .clear_bar = dw_pcie_ep_clear_bar,
+ .map_addr = dw_pcie_ep_map_addr,
+ .unmap_addr = dw_pcie_ep_unmap_addr,
+ .set_msi = dw_pcie_ep_set_msi,
+ .get_msi = dw_pcie_ep_get_msi,
+ .raise_irq = dw_pcie_ep_raise_irq,
+ .start = dw_pcie_ep_start,
+ .stop = dw_pcie_ep_stop,
+};
+
+void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
+{
+ struct pci_epc *epc = ep->epc;
+
+ pci_epc_mem_exit(epc);
+}
+
+int dw_pcie_ep_init(struct dw_pcie_ep *ep)
+{
+ int ret;
+ void *addr;
+ enum pci_barno bar;
+ struct pci_epc *epc;
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ struct device *dev = pci->dev;
+ struct device_node *np = dev->of_node;
+
+ ret = of_property_read_u32(np, "num-ib-windows", &ep->num_ib_windows);
+ if (ret < 0) {
+ dev_err(dev, "unable to read *num-ib-windows* property\n");
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "num-ob-windows", &ep->num_ob_windows);
+ if (ret < 0) {
+ dev_err(dev, "unable to read *num-ob-windows* property\n");
+ return ret;
+ }
+
+ addr = devm_kzalloc(dev, sizeof(phys_addr_t) * ep->num_ob_windows,
+ GFP_KERNEL);
+ if (!addr)
+ return -ENOMEM;
+ ep->outbound_addr = addr;
+
+ for (bar = BAR_0; bar <= BAR_5; bar++)
+ dw_pcie_ep_reset_bar(pci, bar);
+
+ if (ep->ops->ep_init)
+ ep->ops->ep_init(ep);
+
+ epc = devm_pci_epc_create(dev, &epc_ops);
+ if (IS_ERR(epc)) {
+ dev_err(dev, "failed to create epc device\n");
+ return PTR_ERR(epc);
+ }
+
+ ret = of_property_read_u8(np, "max-functions", &epc->max_functions);
+ if (ret < 0)
+ epc->max_functions = 1;
+
+ ret = pci_epc_mem_init(epc, ep->phys_base, ep->addr_size);
+ if (ret < 0) {
+ dev_err(dev, "Failed to initialize address space\n");
+ return ret;
+ }
+
+ ep->epc = epc;
+ epc_set_drvdata(epc, ep);
+ dw_pcie_setup(pci);
+
+ return 0;
+}
diff --git a/drivers/pci/dwc/pcie-designware.c b/drivers/pci/dwc/pcie-designware.c
index 686945d..49b28c8 100644
--- a/drivers/pci/dwc/pcie-designware.c
+++ b/drivers/pci/dwc/pcie-designware.c
@@ -173,6 +173,57 @@ void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index, int type,
dev_err(pci->dev, "iATU is not being enabled\n");
}

+int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int bar,
+ u64 cpu_addr, enum dw_pcie_as_type as_type)
+{
+ int type;
+ void __iomem *base = pci->dbi_base;
+
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_VIEWPORT, 0x4,
+ PCIE_ATU_REGION_INBOUND | index);
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_LOWER_TARGET, 0x4,
+ lower_32_bits(cpu_addr));
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_UPPER_TARGET, 0x4,
+ upper_32_bits(cpu_addr));
+
+ switch (as_type) {
+ case DW_PCIE_AS_MEM:
+ type = PCIE_ATU_TYPE_MEM;
+ break;
+ case DW_PCIE_AS_IO:
+ type = PCIE_ATU_TYPE_IO;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_CR1, 0x4, type);
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_CR2, 0x4, PCIE_ATU_ENABLE |
+ PCIE_ATU_BAR_MODE_ENABLE | (bar << 8));
+ return 0;
+}
+
+void dw_pcie_disable_atu(struct dw_pcie *pci, int index,
+ enum dw_pcie_region_type type)
+{
+ int region;
+ void __iomem *base = pci->dbi_base;
+
+ switch (type) {
+ case DW_PCIE_REGION_INBOUND:
+ region = PCIE_ATU_REGION_INBOUND;
+ break;
+ case DW_PCIE_REGION_OUTBOUND:
+ region = PCIE_ATU_REGION_OUTBOUND;
+ break;
+ default:
+ return;
+ }
+
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_VIEWPORT, 0x4, region | index);
+ dw_pcie_write_dbi(pci, base, PCIE_ATU_CR2, 0x4, ~PCIE_ATU_ENABLE);
+}
+
int dw_pcie_wait_for_link(struct dw_pcie *pci)
{
int retries;
diff --git a/drivers/pci/dwc/pcie-designware.h b/drivers/pci/dwc/pcie-designware.h
index 0ef6ae7..7476234 100644
--- a/drivers/pci/dwc/pcie-designware.h
+++ b/drivers/pci/dwc/pcie-designware.h
@@ -18,6 +18,9 @@
#include <linux/msi.h>
#include <linux/pci.h>

+#include <linux/pci-epc.h>
+#include <linux/pci-epf.h>
+
/* Parameters for the waiting for link up routine */
#define LINK_WAIT_MAX_RETRIES 10
#define LINK_WAIT_USLEEP_MIN 90000
@@ -89,6 +92,13 @@
#define PCIE_GET_ATU_OUTB_UNR_REG_OFFSET(region) \
((0x3 << 20) | ((region) << 9))

+#define MSI_MESSAGE_CONTROL 0x52
+#define MSI_CAP_MMC_SHIFT 1
+#define MSI_CAP_MME_SHIFT 4
+#define MSI_CAP_MME_MASK (7 << MSI_CAP_MME_SHIFT)
+#define MSI_MESSAGE_ADDR_L32 0x54
+#define MSI_MESSAGE_ADDR_U32 0x58
+
/*
* Maximum number of MSI IRQs can be 256 per controller. But keep
* it 32 as of now. Probably we will never need more than 32. If needed,
@@ -99,6 +109,13 @@

struct pcie_port;
struct dw_pcie;
+struct dw_pcie_ep;
+
+enum dw_pcie_region_type {
+ DW_PCIE_REGION_UNKNOWN,
+ DW_PCIE_REGION_INBOUND,
+ DW_PCIE_REGION_OUTBOUND,
+};

struct dw_pcie_host_ops {
int (*rd_own_conf)(struct pcie_port *pp, int where, int size, u32 *val);
@@ -142,6 +159,31 @@ struct pcie_port {
DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
};

+enum dw_pcie_as_type {
+ DW_PCIE_AS_UNKNOWN,
+ DW_PCIE_AS_MEM,
+ DW_PCIE_AS_IO,
+};
+
+struct dw_pcie_ep_ops {
+ void (*ep_init)(struct dw_pcie_ep *ep);
+ int (*raise_irq)(struct dw_pcie_ep *ep, enum pci_epc_irq_type type,
+ u8 interrupt_num);
+};
+
+struct dw_pcie_ep {
+ struct pci_epc *epc;
+ struct dw_pcie_ep_ops *ops;
+ phys_addr_t phys_base;
+ size_t addr_size;
+ u8 bar_to_atu[6];
+ phys_addr_t *outbound_addr;
+ unsigned long ib_window_map;
+ unsigned long ob_window_map;
+ u32 num_ib_windows;
+ u32 num_ob_windows;
+};
+
struct dw_pcie_ops {
u64 (*cpu_addr_fixup)(u64 cpu_addr);
u32 (*read_dbi)(struct dw_pcie *pcie, void __iomem *base, u32 reg,
@@ -149,19 +191,26 @@ struct dw_pcie_ops {
void (*write_dbi)(struct dw_pcie *pcie, void __iomem *base, u32 reg,
int size, u32 val);
int (*link_up)(struct dw_pcie *pcie);
+ int (*start_link)(struct dw_pcie *pcie);
+ void (*stop_link)(struct dw_pcie *pcie);
};

struct dw_pcie {
struct device *dev;
void __iomem *dbi_base;
+ void __iomem *dbi_base2;
u32 num_viewport;
u8 iatu_unroll_enabled;
struct pcie_port pp;
+ struct dw_pcie_ep ep;
const struct dw_pcie_ops *ops;
};

#define to_dw_pcie_from_pp(port) container_of((port), struct dw_pcie, pp)

+#define to_dw_pcie_from_ep(endpoint) \
+ container_of((endpoint), struct dw_pcie, ep)
+
int dw_pcie_read(void __iomem *addr, int size, u32 *val);
int dw_pcie_write(void __iomem *addr, int size, u32 val);

@@ -174,6 +223,10 @@ void dw_pcie_write_dbi(struct dw_pcie *pci, void __iomem *base, u32 reg,
void dw_pcie_prog_outbound_atu(struct dw_pcie *pci, int index,
int type, u64 cpu_addr, u64 pci_addr,
u32 size);
+int dw_pcie_prog_inbound_atu(struct dw_pcie *pci, int index, int bar,
+ u64 cpu_addr, enum dw_pcie_as_type as_type);
+void dw_pcie_disable_atu(struct dw_pcie *pci, int index,
+ enum dw_pcie_region_type type);
void dw_pcie_setup(struct dw_pcie *pci);

#ifdef CONFIG_PCIE_DW_HOST
@@ -200,4 +253,23 @@ static inline int dw_pcie_host_init(struct pcie_port *pp)
return 0;
}
#endif
+
+#ifdef CONFIG_PCIE_DW_EP
+void dw_pcie_ep_linkup(struct dw_pcie_ep *ep);
+int dw_pcie_ep_init(struct dw_pcie_ep *ep);
+void dw_pcie_ep_exit(struct dw_pcie_ep *ep);
+#else
+static inline void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
+{
+}
+
+static inline int dw_pcie_ep_init(struct dw_pcie_ep *ep)
+{
+ return 0;
+}
+
+static inline void dw_pcie_ep_exit(struct dw_pcie_ep *ep)
+{
+}
+#endif
#endif /* _PCIE_DESIGNWARE_H */
--
1.7.9.5