From 9a8bcabd8adac3382bc23bef450a6793e5144110 Mon Sep 17 00:00:00 2001 From: Mario Six Date: Thu, 9 Aug 2018 14:51:18 +0200 Subject: [PATCH] axi: Add AXI sandbox driver and simple emulator Add test infrastructure and tests for the AXI uclass. Reviewed-by: Simon Glass Signed-off-by: Mario Six --- arch/sandbox/include/asm/axi.h | 66 ++++++++++++++++++++++ drivers/axi/Kconfig | 7 +++ drivers/axi/Makefile | 3 + drivers/axi/axi-emul-uclass.c | 85 ++++++++++++++++++++++++++++ drivers/axi/axi_sandbox.c | 77 ++++++++++++++++++++++++++ drivers/axi/sandbox_store.c | 123 +++++++++++++++++++++++++++++++++++++++++ include/axi.h | 74 +++++++++++++++++++------ include/dm/uclass-id.h | 1 + 8 files changed, 419 insertions(+), 17 deletions(-) create mode 100644 arch/sandbox/include/asm/axi.h create mode 100644 drivers/axi/axi-emul-uclass.c create mode 100644 drivers/axi/axi_sandbox.c create mode 100644 drivers/axi/sandbox_store.c diff --git a/arch/sandbox/include/asm/axi.h b/arch/sandbox/include/asm/axi.h new file mode 100644 index 0000000..d483f7b --- /dev/null +++ b/arch/sandbox/include/asm/axi.h @@ -0,0 +1,66 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * (C) Copyright 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + */ + +#ifndef __asm_axi_h +#define __asm_axi_h + +#define axi_emul_get_ops(dev) ((struct axi_emul_ops *)(dev)->driver->ops) + +/** + * axi_sandbox_get_emul() - Retrieve a pointer to a AXI emulation device + * @bus: The AXI bus from which to retrieve a emulation device + * @address: The address of a transfer that should be handled by a emulation + * device + * @length: The data width of a transfer that should be handled by a emulation + * device + * @emulp: Pointer to a buffer receiving the emulation device that handles + * the transfer specified by the address and length parameters + * + * To test the AXI uclass, we implement a simple AXI emulation device, which is + * a virtual device on a AXI bus that exposes a simple storage interface: When + * reading and writing from the device, the addresses are translated to offsets + * within the device's storage. For write accesses the data is written to the + * specified storage offset, and for read accesses the data is read from the + * specified storage offset. + * + * A DTS entry might look like this: + * + * axi: axi@0 { + * compatible = "sandbox,axi"; + * #address-cells = <0x1>; + * #size-cells = <0x1>; + * store@0 { + * compatible = "sandbox,sandbox_store"; + * reg = <0x0 0x400>; + * }; + * }; + * + * This function may then be used to retrieve the pointer to the sandbox_store + * emulation device given the AXI bus device, and the data (address, data + * width) of a AXI transfer which should be handled by a emulation device. + * + * Return: 0 of OK, -ENODEV if no device capable of handling the specified + * transfer exists or the device could not be retrieved + */ +int axi_sandbox_get_emul(struct udevice *bus, ulong address, uint length, + struct udevice **emulp); +/** + * axi_get_store() - Get address of internal storage of a emulated AXI device + * @dev: Emulated AXI device to get the pointer of the internal storage + * for. + * @storep: Pointer to the internal storage of the emulated AXI device. + * + * To preset or read back the contents internal storage of the emulated AXI + * device, this function returns the pointer to the storage. Changes to the + * contents of the storage are reflected when using the AXI read/write API + * methods, and vice versa, so by using this method expected read data can be + * set up in advance, and written data can be checked in unit tests. + * + * Return: 0 if OK, -ve on error. + */ +int axi_get_store(struct udevice *dev, u8 **storep); + +#endif /* __asm_axi_h */ diff --git a/drivers/axi/Kconfig b/drivers/axi/Kconfig index ae80c98..f81d843 100644 --- a/drivers/axi/Kconfig +++ b/drivers/axi/Kconfig @@ -22,4 +22,11 @@ config IHS_AXI Interface (IHS AXI) bus on a gdsys IHS FPGA used to communicate with IP cores in the FPGA (e.g. video transmitter cores). +config AXI_SANDBOX + bool "Enable AXI sandbox driver" + depends on DM + help + Support AXI (Advanced eXtensible Interface) emulation for the sandbox + environment. + endif diff --git a/drivers/axi/Makefile b/drivers/axi/Makefile index 18d9380..66b6c5a 100644 --- a/drivers/axi/Makefile +++ b/drivers/axi/Makefile @@ -7,3 +7,6 @@ obj-$(CONFIG_AXI) += axi-uclass.o obj-$(CONFIG_IHS_AXI) += ihs_axi.o +obj-$(CONFIG_SANDBOX) += axi-emul-uclass.o +obj-$(CONFIG_SANDBOX) += sandbox_store.o +obj-$(CONFIG_AXI_SANDBOX) += axi_sandbox.o diff --git a/drivers/axi/axi-emul-uclass.c b/drivers/axi/axi-emul-uclass.c new file mode 100644 index 0000000..06c4200 --- /dev/null +++ b/drivers/axi/axi-emul-uclass.c @@ -0,0 +1,85 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + */ + +#include +#include +#include +#include +#include + +int axi_sandbox_get_emul(struct udevice *bus, ulong address, + enum axi_size_t size, struct udevice **emulp) +{ + struct udevice *dev; + u32 reg[2]; + uint offset; + + switch (size) { + case AXI_SIZE_8: + offset = 1; + break; + case AXI_SIZE_16: + offset = 2; + break; + case AXI_SIZE_32: + offset = 4; + break; + default: + debug("%s: Unknown AXI transfer size '%d'", bus->name, size); + offset = 0; + } + + /* + * Note: device_find_* don't activate the devices; they're activated + * as-needed below. + */ + for (device_find_first_child(bus, &dev); + dev; + device_find_next_child(&dev)) { + int ret; + + ret = dev_read_u32_array(dev, "reg", reg, ARRAY_SIZE(reg)); + if (ret) { + debug("%s: Could not read 'reg' property of %s\n", + bus->name, dev->name); + continue; + } + + /* + * Does the transfer's address fall into this device's address + * space? + */ + if (address >= reg[0] && address <= reg[0] + reg[1] - offset) { + /* If yes, activate it... */ + if (device_probe(dev)) { + debug("%s: Could not activate %s\n", + bus->name, dev->name); + return -ENODEV; + } + + /* ...and return it */ + *emulp = dev; + return 0; + } + } + + return -ENODEV; +} + +int axi_get_store(struct udevice *dev, u8 **storep) +{ + struct axi_emul_ops *ops = axi_emul_get_ops(dev); + + if (!ops->get_store) + return -ENOSYS; + + return ops->get_store(dev, storep); +} + +UCLASS_DRIVER(axi_emul) = { + .id = UCLASS_AXI_EMUL, + .name = "axi_emul", +}; diff --git a/drivers/axi/axi_sandbox.c b/drivers/axi/axi_sandbox.c new file mode 100644 index 0000000..b91c91f --- /dev/null +++ b/drivers/axi/axi_sandbox.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + */ + +#include +#include +#include +#include + +/* + * This driver implements a AXI bus for the sandbox architecture for testing + * purposes. + * + * The bus forwards every access to it to a special AXI emulation device (which + * it gets via the axi_emul_get_ops function) that implements a simple + * read/write storage. + * + * The emulator device must still be contained in the device tree in the usual + * way, since configuration data for the storage is read from the DT. + */ + +static int axi_sandbox_read(struct udevice *bus, ulong address, void *data, + enum axi_size_t size) +{ + struct axi_emul_ops *ops; + struct udevice *emul; + int ret; + + /* Get emulator device */ + ret = axi_sandbox_get_emul(bus, address, size, &emul); + if (ret) + return ret == -ENODEV ? 0 : ret; + /* Forward all reads to the AXI emulator */ + ops = axi_emul_get_ops(emul); + if (!ops || !ops->read) + return -ENOSYS; + + return ops->read(emul, address, data, size); +} + +static int axi_sandbox_write(struct udevice *bus, ulong address, void *data, + enum axi_size_t size) +{ + struct axi_emul_ops *ops; + struct udevice *emul; + int ret; + + /* Get emulator device */ + ret = axi_sandbox_get_emul(bus, address, size, &emul); + if (ret) + return ret == -ENODEV ? 0 : ret; + /* Forward all writes to the AXI emulator */ + ops = axi_emul_get_ops(emul); + if (!ops || !ops->write) + return -ENOSYS; + + return ops->write(emul, address, data, size); +} + +static const struct udevice_id axi_sandbox_ids[] = { + { .compatible = "sandbox,axi" }, + { /* sentinel */ } +}; + +static const struct axi_ops axi_sandbox_ops = { + .read = axi_sandbox_read, + .write = axi_sandbox_write, +}; + +U_BOOT_DRIVER(axi_sandbox_bus) = { + .name = "axi_sandbox_bus", + .id = UCLASS_AXI, + .of_match = axi_sandbox_ids, + .ops = &axi_sandbox_ops, +}; diff --git a/drivers/axi/sandbox_store.c b/drivers/axi/sandbox_store.c new file mode 100644 index 0000000..d724f19 --- /dev/null +++ b/drivers/axi/sandbox_store.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + */ + +#include +#include +#include + +/** + * struct sandbox_store_priv - Private data structure of a AXI store device + * @store: The buffer holding the device's internal memory, which is read from + * and written to using the driver's methods + */ +struct sandbox_store_priv { + u8 *store; +}; + +/** + * copy_axi_data() - Copy data from source to destination with a given AXI + * transfer width + * @src: Pointer to the data source from where data will be read + * @dst: Pointer to the data destination where data will be written to + * @size: Size of the data to be copied given by a axi_size_t enum value + * + * Return: 0 if OK, -ve on error + */ +static int copy_axi_data(void *src, void *dst, enum axi_size_t size) +{ + switch (size) { + case AXI_SIZE_8: + *((u8 *)dst) = *((u8 *)src); + return 0; + case AXI_SIZE_16: + *((u16 *)dst) = be16_to_cpu(*((u16 *)src)); + return 0; + case AXI_SIZE_32: + *((u32 *)dst) = be32_to_cpu(*((u32 *)src)); + return 0; + default: + debug("%s: Unknown AXI transfer size '%d'\n", __func__, size); + return -EINVAL; + } +} + +static int sandbox_store_read(struct udevice *dev, ulong address, void *data, + enum axi_size_t size) +{ + struct sandbox_store_priv *priv = dev_get_priv(dev); + + return copy_axi_data(priv->store + address, data, size); +} + +static int sandbox_store_write(struct udevice *dev, ulong address, void *data, + enum axi_size_t size) +{ + struct sandbox_store_priv *priv = dev_get_priv(dev); + + return copy_axi_data(data, priv->store + address, size); +} + +static int sandbox_store_get_store(struct udevice *dev, u8 **store) +{ + struct sandbox_store_priv *priv = dev_get_priv(dev); + + *store = priv->store; + + return 0; +} + +static const struct udevice_id sandbox_store_ids[] = { + { .compatible = "sandbox,sandbox_store" }, + { /* sentinel */ } +}; + +static const struct axi_emul_ops sandbox_store_ops = { + .read = sandbox_store_read, + .write = sandbox_store_write, + .get_store = sandbox_store_get_store, +}; + +static int sandbox_store_probe(struct udevice *dev) +{ + struct sandbox_store_priv *priv = dev_get_priv(dev); + u32 reg[2]; + int ret; + + ret = dev_read_u32_array(dev, "reg", reg, ARRAY_SIZE(reg)); + if (ret) { + debug("%s: Could not read 'reg' property\n", dev->name); + return -EINVAL; + } + + /* + * Allocate the device's internal storage that will be read + * from/written to + */ + priv->store = calloc(reg[1], 1); + if (!priv->store) + return -ENOMEM; + + return 0; +} + +static int sandbox_store_remove(struct udevice *dev) +{ + struct sandbox_store_priv *priv = dev_get_priv(dev); + + free(priv->store); + + return 0; +} + +U_BOOT_DRIVER(sandbox_axi_store) = { + .name = "sandbox_axi_store", + .id = UCLASS_AXI_EMUL, + .of_match = sandbox_store_ids, + .ops = &sandbox_store_ops, + .priv_auto_alloc_size = sizeof(struct sandbox_store_priv), + .probe = sandbox_store_probe, + .remove = sandbox_store_remove, +}; diff --git a/include/axi.h b/include/axi.h index 2ff81c1..3e40692 100644 --- a/include/axi.h +++ b/include/axi.h @@ -1,48 +1,47 @@ /* SPDX-License-Identifier: GPL-2.0+ */ /* - * (C) Copyright 2017 - * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc + * (C) Copyright 2017, 2018 + * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc */ #ifndef _AXI_H_ #define _AXI_H_ +/** + * enum axi_size_t - Determine size of AXI transfer + * @AXI_SIZE_8: AXI sransfer is 8-bit wide + * @AXI_SIZE_16: AXI sransfer is 16-bit wide + * @AXI_SIZE_32: AXI sransfer is 32-bit wide + */ enum axi_size_t { AXI_SIZE_8, AXI_SIZE_16, AXI_SIZE_32, }; -/** - * struct axi_ops - driver operations for AXI uclass - * - * Drivers should support these operations unless otherwise noted. These - * operations are intended to be used by uclass code, not directly from - * other code. - */ struct axi_ops { /** * read() - Read a single value from a specified address on a AXI bus - * * @dev: AXI bus to read from. * @address: The address to read from. * @data: Pointer to a variable that takes the data value read * from the address on the AXI bus. * @size: The size of the data to be read. - * @return 0 if OK, -ve on error. + * + * Return: 0 if OK, -ve on error. */ int (*read)(struct udevice *dev, ulong address, void *data, enum axi_size_t size); /** * write() - Write a single value to a specified address on a AXI bus - * * @dev: AXI bus to write to. * @address: The address to write to. * @data: Pointer to the data value to be written to the address * on the AXI bus. * @size: The size of the data to write. - * @return 0 if OK, -ve on error. + * + * Return 0 if OK, -ve on error. */ int (*write)(struct udevice *dev, ulong address, void *data, enum axi_size_t size); @@ -52,27 +51,68 @@ struct axi_ops { /** * axi_read() - Read a single value from a specified address on a AXI bus - * * @dev: AXI bus to read from. * @address: The address to read from. * @data: Pointer to a variable that takes the data value read from the * address on the AXI bus. * @size: The size of the data to write. - * @return 0 if OK, -ve on error. + * + * Return: 0 if OK, -ve on error. */ int axi_read(struct udevice *dev, ulong address, void *data, enum axi_size_t size); /** * axi_write() - Write a single value to a specified address on a AXI bus - * * @dev: AXI bus to write to. * @address: The address to write to. * @data: Pointer to the data value to be written to the address on the * AXI bus. * @size: The size of the data to write. - * @return 0 if OK, -ve on error. + * + * Return: 0 if OK, -ve on error. */ int axi_write(struct udevice *dev, ulong address, void *data, enum axi_size_t size); + +struct axi_emul_ops { + /** + * read() - Read a single value from a specified address on a AXI bus + * @dev: AXI bus to read from. + * @address: The address to read from. + * @data: Pointer to a variable that takes the data value read + * from the address on the AXI bus. + * @size: The size of the data to be read. + * + * Return: 0 if OK, -ve on error. + */ + int (*read)(struct udevice *dev, ulong address, void *data, + enum axi_size_t size); + + /** + * write() - Write a single value to a specified address on a AXI bus + * @dev: AXI bus to write to. + * @address: The address to write to. + * @data: Pointer to the data value to be written to the address + * on the AXI bus. + * @size: The size of the data to write. + * + * Return: 0 if OK, -ve on error. + */ + int (*write)(struct udevice *dev, ulong address, void *data, + enum axi_size_t size); + + /** + * get_store() - Get address of internal storage of a emulated AXI + * device + * @dev: Emulated AXI device to get the pointer of the internal + * storage for. + * @storep: Pointer to the internal storage of the emulated AXI + * device. + * + * Return: 0 if OK, -ve on error. + */ + int (*get_store)(struct udevice *dev, u8 **storep); +}; + #endif diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index 618f43a..7027ea0 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -23,6 +23,7 @@ enum uclass_id { UCLASS_I2C_EMUL, /* sandbox I2C device emulator */ UCLASS_PCI_EMUL, /* sandbox PCI device emulator */ UCLASS_USB_EMUL, /* sandbox USB bus device emulator */ + UCLASS_AXI_EMUL, /* sandbox AXI bus device emulator */ UCLASS_SIMPLE_BUS, /* bus with child devices */ /* U-Boot uclasses start here - in alphabetical order */