Re: [PATCH v7 11/37] pci: pci-sh7751: Add SH7751 PCI driver
From: Mayank Rana
Date: Mon Apr 08 2024 - 17:33:58 EST
Hi,
On 4/3/2024 9:59 PM, Yoshinori Sato wrote:
Renesas SH7751 CPU Internal PCI Controller driver.
Signed-off-by: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
---
drivers/pci/controller/Kconfig | 9 +
drivers/pci/controller/Makefile | 1 +
drivers/pci/controller/pci-sh7751.c | 342 ++++++++++++++++++++++++++++
3 files changed, 352 insertions(+)
create mode 100644 drivers/pci/controller/pci-sh7751.c
diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index e534c02ee34f..a2fd917a2e03 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -353,6 +353,15 @@ config PCIE_XILINX_CPM
Say 'Y' here if you want kernel support for the
Xilinx Versal CPM host bridge.
+config PCI_SH7751
+ bool "Renesas SH7751 PCI controller"
+ depends on OF
+ depends on CPU_SUBTYPE_SH7751 || CPU_SUBTYPE_SH7751R || COMPILE_TEST
+ select PCI_HOST_COMMON
+ help
+ Say 'Y' here if you want kernel to support the Renesas SH7751 PCI
+ Host Bridge driver.
+
source "drivers/pci/controller/cadence/Kconfig"
source "drivers/pci/controller/dwc/Kconfig"
source "drivers/pci/controller/mobiveil/Kconfig"
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index f2b19e6174af..aa97e5d74e58 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -40,6 +40,7 @@ obj-$(CONFIG_PCI_LOONGSON) += pci-loongson.o
obj-$(CONFIG_PCIE_HISI_ERR) += pcie-hisi-error.o
obj-$(CONFIG_PCIE_APPLE) += pcie-apple.o
obj-$(CONFIG_PCIE_MT7621) += pcie-mt7621.o
+obj-$(CONFIG_PCI_SH7751) += pci-sh7751.o
# pcie-hisi.o quirks are needed even without CONFIG_PCIE_DW
obj-y += dwc/
diff --git a/drivers/pci/controller/pci-sh7751.c b/drivers/pci/controller/pci-sh7751.c
new file mode 100644
index 000000000000..a5340689f737
--- /dev/null
+++ b/drivers/pci/controller/pci-sh7751.c
@@ -0,0 +1,342 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SH7751 PCI driver
+ * Copyright (C) 2023 Yoshinori Sato
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/pci-ecam.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/pci.h>
+#include <linux/dma-direct.h>
+#include <asm/addrspace.h>
can you consider to rearranging headers into alphabetically sorted order ?
+
+/* PCICR and PCICLKCR write enable magic key */
+#define PCIC_WE_KEY (0xa5 << 24)
+
+/* PCIC registers */
+/* 0x0000 - 0x00ff mapped to PCI device configuration space */
+#define PCIC_PCICR 0x100 /* PCI Control Register */
+#define PCIC_PCICR_TRSB BIT(9) /* Target Read Single */
+#define PCIC_PCICR_BSWP BIT(8) /* Target Byte Swap */
+#define PCIC_PCICR_PLUP BIT(7) /* Enable PCI Pullup */
+#define PCIC_PCICR_ARBM BIT(6) /* PCI Arbitration Mode */
+#define PCIC_PCICR_MD10 BIT(5) /* MD10 status */
+#define PCIC_PCICR_MD9 BIT(4) /* MD9 status */
+#define PCIC_PCICR_SERR BIT(3) /* SERR output assert */
+#define PCIC_PCICR_INTA BIT(2) /* INTA output assert */
+#define PCIC_PCICR_PRST BIT(1) /* PCI Reset Assert */
+#define PCIC_PCICR_CFIN BIT(0) /* Central Fun. Init Done */
+
+#define PCIC_PCILSR0 0x104 /* PCI Local Space Register0 */
+#define PCIC_PCILSR1 0x108 /* PCI Local Space Register1 */
+#define PCIC_PCILAR0 0x10c /* PCI Local Addr Register1 */
+#define PCIC_PCILAR1 0x110 /* PCI Local Addr Register1 */
+#define PCIC_PCIINT 0x114 /* PCI Interrupt Register */
+#define PCIC_PCIINTM 0x118 /* PCI Interrupt Mask */
+#define PCIC_PCIALR 0x11c /* Error Address Register */
+#define PCIC_PCICLR 0x120 /* Error Command/Data */
+#define PCIC_PCIAINT 0x130 /* Arbiter Interrupt Register */
+#define PCIC_PCIAINTM 0x134 /* Arbiter Int. Mask Register */
+#define PCIC_PCIBMLR 0x138 /* Error Bus Master Register */
+#define PCIC_PCIDMABT 0x140 /* DMA Transfer Arb. Register */
+#define PCIC_PCIPAR 0x1c0 /* PIO Address Register */
+#define PCIC_PCIMBR 0x1c4 /* Memory Base Address */
+#define PCIC_PCIIOBR 0x1c8 /* I/O Base Address Register */
+
+#define PCIC_PCIPINT 0x1cc /* Power Mgmnt Int. Register */
+#define PCIC_PCIPINT_D3 BIT(1) /* D3 Pwr Mgmt. Interrupt */
+#define PCIC_PCIPINT_D0 BIT(0) /* D0 Pwr Mgmt. Interrupt */
+
+#define PCIC_PCIPINTM 0x1d0 /* Power Mgmnt Mask Register */
+#define PCIC_PCICLKR 0x1d4 /* Clock Ctrl. Register */
+#define PCIC_PCIBCR1 0x1e0 /* Memory BCR1 Register */
+#define PCIC_PCIBCR2 0x1e4 /* Memory BCR2 Register */
+#define PCIC_PCIWCR1 0x1e8 /* Wait Control 1 Register */
+#define PCIC_PCIWCR2 0x1ec /* Wait Control 2 Register */
+#define PCIC_PCIWCR3 0x1f0 /* Wait Control 3 Register */
+#define PCIC_PCIMCR 0x1f4 /* Memory Control Register */
+#define PCIC_PCIBCR3 0x1f8 /* Memory BCR3 Register */
+#define PCIC_PCIPDR 0x220 /* Port IO Data Register */
+
+/* PCI IDs */
+/* Hitachi is the company that led to Renesas. */
+/* The SH7751 was designed by Hitachi, so it has a Hitachi ID. */
multi-line comments way ?
+#define PCI_VENDOR_ID_HITACHI 0x1054
+#define PCI_DEVICE_ID_SH7751 0x3505
+#define PCI_DEVICE_ID_SH7751R 0x350e
+
+/* BSC registers */
+/* Copy BSC setting to PCI BSC */
+#define BSC_BCR1 0x0000
+#define BSC_BCR1_SLAVE BIT(30)
+#define BSC_BCR1_BRQEN BIT(19)
+#define BSC_BCR2 0x0004
+#define BSC_BCR3 0x0050
+#define BSC_WCR1 0x0008
+#define BSC_WCR2 0x000c
+#define BSC_WCR3 0x0010
+#define BSC_MCR 0x0014
+#define BSC_MCR_MRSET BIT(30)
+#define BSC_MCR_RFSH BIT(2)
+
+/* PCIC access wrapper */
+#define pcic_writel(val, base, reg) writel(val, base + (reg))
+#define pcic_readl(base, reg) readl(base + (reg))
Do you really needed these new macros ? Is it for better readability ?
+/*
+ * We need to avoid collisions with `mirrored' VGA ports
+ * and other strange ISA hardware, so we always want the
+ * addresses to be allocated in the 0x000-0x0ff region
+ * modulo 0x400.
+ */
+#define IO_REGION_BASE 0x1000
+resource_size_t pcibios_align_resource(void *data, const struct resource *res,
+ resource_size_t size, resource_size_t align)
+{
+ resource_size_t start = res->start;
+
+ if (res->flags & IORESOURCE_IO) {
+ if (start < PCIBIOS_MIN_IO + IO_REGION_BASE)
+ start = PCIBIOS_MIN_IO + IO_REGION_BASE;
+
+ /*
+ * Put everything into 0x00-0xff region modulo 0x400.
+ */
single line comment would work. no ?
+ if (start & 0x300)
+ start = (start + 0x3ff) & ~0x3ff;
+ }
+
+ return start;
+}
+
+static int setup_pci_bsc(struct device *dev, void __iomem *pcic,
+ void __iomem *bsc, unsigned int area, bool bcr3)
+{
+ u32 word;
+
+ word = __raw_readl(bsc + BSC_BCR1);
+ /* check BCR for SDRAM in area */
+ if (((word >> area) & 1) == 0) {
+ dev_err(dev, "Area %u is not configured for SDRAM. BCR1=0x%x\n",
+ area, word);
+ return -EINVAL;
+ }
+ word |= BSC_BCR1_SLAVE; /* PCIC BSC is slave only */
+ pcic_writel(word, pcic, PCIC_PCIBCR1);
+
+ word = __raw_readw(bsc + BSC_BCR2);
+ /* check BCR2 for 32bit SDRAM interface*/
+ if (((word >> (area << 1)) & 0x3) != 0x3) {
+ dev_err(dev, "Area %u is not 32 bit SDRAM. BCR2=0x%x\n",
+ area, word);
+ return -EINVAL;
+ }
+ pcic_writel(word, pcic, PCIC_PCIBCR2);
+
+ if (bcr3) {
+ /* BCR3 have only SH7751R */
+ word = __raw_readw(bsc + BSC_BCR3);
+ pcic_writel(word, pcic, PCIC_PCIBCR3);
+ }
+
+ /* configure the wait control registers */
+ word = __raw_readl(bsc + BSC_WCR1);
+ pcic_writel(word, pcic, PCIC_PCIWCR1);
+ word = __raw_readl(bsc + BSC_WCR2);
+ pcic_writel(word, pcic, PCIC_PCIWCR2);
+ word = __raw_readl(bsc + BSC_WCR3);
+ pcic_writel(word, pcic, PCIC_PCIWCR3);
+ word = __raw_readl(bsc + BSC_MCR);
+ /* Clear MRSET and RFSH bit */
+ word &= ~(BSC_MCR_MRSET | BSC_MCR_RFSH);
+ pcic_writel(word, pcic, PCIC_PCIMCR);
+
+ return 0;
+}
+
+#define NUM_AREA 7
+static int set_pci_ranges(struct device *dev,
+ void __iomem *pcic, void __iomem *bsc, bool bcr3)
+{
+ struct resource_entry *dma, *tmp;
+ struct pci_host_bridge *bridge;
+ u32 bsc_done[NUM_AREA];
+ unsigned int la;
+
+ bridge = dev_get_drvdata(dev);
+ pcic_writel(0, pcic, PCIC_PCILAR0);
+ pcic_writel(0, pcic, PCIC_PCILAR1);
+ la = 0;
+ memset(&bsc_done, 0, sizeof(bsc_done));
+ resource_list_for_each_entry_safe(dma, tmp, &bridge->dma_ranges) {
+ struct resource *res = dma->res;
+ unsigned int area;
+ u32 word;
+
+ switch (resource_type(res)) {
+ case IORESOURCE_IO:
+ /* BAR0 is I/O space */
+ word = res->start | 1;
+ pcic_writel(word, pcic, PCI_BASE_ADDRESS_0);
+ word = pcic_readl(pcic, PCI_COMMAND);
+ word |= PCI_COMMAND_IO;
+ pcic_writel(word, pcic, PCI_COMMAND);
+ break;
+ case IORESOURCE_MEM:
+ if (la > 4) {
+ dev_err(dev, "Invalid range definition.\n");
+ return -EINVAL;
+ }
+ area = (res->start >> 26) & 0x07;
+ word = res->end - res->start;
+ if (area >= NUM_AREA) {
+ /* Area 7 is reserved. */
+ dev_info(dev, "Invalid local address 0x%08x. Ignore it.\n",
+ res->start);
+ break;
+ }
+ pcic_writel(res->start, pcic, PCI_BASE_ADDRESS_1 + la);
+ /* if dummy entry, skip BSC setup */
+ if (word < 4)
+ break;
+ /* BAR1 is local area 0, BAR2 is local area 1 */
+ pcic_writel(word, pcic, PCIC_PCILSR0 + la);
+ word = P2SEGADDR(res->start);
+ pcic_writel(word, pcic, PCIC_PCILAR0 + la);
+ la += 4;
+ if (!bsc_done[area]) {
+ /* check BCR for SDRAM in specified area. And setup PCI BSC. */
+ if (setup_pci_bsc(dev, pcic, bsc, area, bcr3))
+ return -EINVAL;
+ bsc_done[area] = 1;
+ }
+ break;
+ }
+ }
+ return 0;
+}
+
+static int sh7751_pci_probe(struct platform_device *pdev)
+{
+ struct resource *res, *bscres;
+ void __iomem *pcic;
+ void __iomem *bsc;
+ u16 vid, did;
+ u32 word;
+ int ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (IS_ERR(res))
+ return PTR_ERR(res);
+ pcic = ioremap(res->start, res->end - res->start + 1);
Can you consider using devm_platform_ioremap_resource() API ?
+ bscres = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ bsc = devm_ioremap_resource(&pdev->dev, bscres);
+ if (IS_ERR(bsc))
+ return PTR_ERR(bsc);
Same as above.
+ /* check for SH7751/SH7751R hardware */
+ word = pcic_readl(pcic, PCI_VENDOR_ID);
+ vid = word & 0xffff;
+ did = word >> 16;
+ if ((vid != PCI_VENDOR_ID_HITACHI) ||
+ ((did != PCI_DEVICE_ID_SH7751) &&
+ (did != PCI_DEVICE_ID_SH7751R))) {
+ dev_err(&pdev->dev, "This is not an SH7751(R)\n");
error handling missing iounmap(pcic)
+ return -ENODEV;
+ }
+ dev_info(&pdev->dev, "PCI core found at %pR\n", res);
+
+ /* Set the BCR's to enable PCI access */
+ word = __raw_readl(bsc + BSC_BCR1);
+ word |= BSC_BCR1_BRQEN;
+ __raw_writel(word, bsc + BSC_BCR1);
+
+ /* Turn the clocks back on (not done in reset)*/
+ pcic_writel(PCIC_WE_KEY | 0, pcic, PCIC_PCICLKR);
+ /* Clear Powerdown IRQ's (not done in reset) */
+ word = PCIC_PCIPINT_D3 | PCIC_PCIPINT_D0;
+ pcic_writel(word, pcic, PCIC_PCIPINT);
+
+ /* set the command/status */
+ word = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
+ PCI_COMMAND_PARITY | PCI_COMMAND_WAIT;
+ pcic_writel(word, pcic, PCI_COMMAND);
+
+ /* define this host as the host bridge */
+ word = PCI_BASE_CLASS_BRIDGE << 24;
+ pcic_writel(word, pcic, PCI_CLASS_REVISION);
+
+ ret = pci_host_common_probe(pdev);
+ if (ret) {
+ dev_err(&pdev->dev, "Initialize failed (%d)\n", ret);
+ return ret;
+ }
+
+ /* Set IO and Mem windows to local address */
+ if (set_pci_ranges(&pdev->dev, pcic, bsc,
+ did == PCI_DEVICE_ID_SH7751R))
+ return -EINVAL;
error handling to call pci_host_common_remove() ?
+ pcic_writel(0, pcic, PCIC_PCIIOBR);
+
+ if (of_property_read_bool(pdev->dev.of_node, "renesas,bus-arbit-round-robin"))
+ word |= BIT(0);
+ else
+ word = 0;
+ pcic_writel(word, pcic, PCIC_PCIDMABT);
+
+ /* SH7751 init done, set central function init complete */
+ /* use round robin mode to stop a device starving/overrunning */
multi-line comment ?
+ word = PCIC_PCICR_CFIN | PCIC_PCICR_ARBM;
+ pcic_writel(PCIC_WE_KEY | word, pcic, PCIC_PCICR);
+
+ return 0;
+}
+
+/*
+ * Direct access to PCI hardware...
+ */
+#define CONFIG_CMD(bus, devfn, where) \
+ (0x80000000 | (bus->number << 16) | (devfn << 8) | (where & ~3))
+
+static void __iomem *sh4_pci_map_bus(struct pci_bus *bus,
+ unsigned int devfn, int where)
+{
+ struct pci_config_window *cfg = bus->sysdata;
+ void __iomem *pcic = (void __iomem *)cfg->res.start;
+
+ pcic_writel(CONFIG_CMD(bus, devfn, where), pcic, PCIC_PCIPAR);
+ return pcic + PCIC_PCIPDR;
+}
+
+static const struct pci_ecam_ops pci_sh7751_bus_ops = {
+ .pci_ops = {
+ .map_bus = sh4_pci_map_bus,
+ .read = pci_generic_config_read32,
+ .write = pci_generic_config_write32,
+ }
+};
+
+static const struct of_device_id sh7751_pci_of_match[] = {
+ { .compatible = "renesas,sh7751-pci",
+ .data = &pci_sh7751_bus_ops },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sh7751_pci_of_match);
+
+static struct platform_driver sh7751_pci_driver = {
+ .driver = {
+ .name = "sh7751-pci",
+ .of_match_table = sh7751_pci_of_match,
+ },
+ .probe = sh7751_pci_probe,
+};
+module_platform_driver(sh7751_pci_driver);
+
+MODULE_DESCRIPTION("SH7751 PCI driver");