[PATCH v7 2/5] soc: aspeed: Add XDMA Engine Driver

Eddie James
2020-04-02T19:50:18Z

The XDMA engine embedded in the AST2500 and AST2600 SOCs performs PCI
DMA operations between the SOC (acting as a BMC) and a host processor
in a server.

This commit adds a driver to control the XDMA engine and adds functions
to initialize the hardware and memory and start DMA operations.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Andrew Jeffrey <andrew@aj.id.au>
---
Changes since v6:
- Switch to use a chunk of reserved memory from the devicetree rather than
simply reading the address and size
- Add PCI-E root complex reset
- Fix buffer overrun in aspeed_xdma_start
- Switch to usleep_range with a smaller time than the old msleep(10) because
that time is for toggling the clock, which we don't do during reset and
should be done by the clock driver anyway
- Set some additional bit in the SCU necessary for XDMA to work
- Refactor probe error handling near the end

MAINTAINERS | 2 +
drivers/soc/aspeed/Kconfig | 8 +
drivers/soc/aspeed/Makefile | 1 +
drivers/soc/aspeed/aspeed-xdma.c | 840 +++++++++++++++++++++++++++++++
include/uapi/linux/aspeed-xdma.h | 38 ++
5 files changed, 889 insertions(+)
create mode 100644 drivers/soc/aspeed/aspeed-xdma.c
create mode 100644 include/uapi/linux/aspeed-xdma.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 619a2d559ce2..96aad6b2e624 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2776,6 +2776,8 @@ M: Eddie James <eajames@linux.ibm.com>
L: linux-aspeed@lists.ozlabs.org (moderated for non-subscribers)
S: Maintained
F: Documentation/devicetree/bindings/soc/aspeed/xdma.txt
+F: drivers/soc/aspeed/aspeed-xdma.c
+F: include/uapi/linux/aspeed-xdma.h

ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
M: Corentin Chary <corentin.chary@gmail.com>
diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig
index 323e177aa74d..2a6c16f9e50b 100644
--- a/drivers/soc/aspeed/Kconfig
+++ b/drivers/soc/aspeed/Kconfig
@@ -29,4 +29,12 @@ config ASPEED_P2A_CTRL
ioctl()s, the driver also provides an interface for userspace mappings to
a pre-defined region.

+config ASPEED_XDMA
+ tristate "Aspeed XDMA Engine Driver"
+ depends on SOC_ASPEED && REGMAP && MFD_SYSCON && HAS_DMA
+ help
+ Enable support for the Aspeed XDMA Engine found on the Aspeed AST2XXX
+ SOCs. The XDMA engine can perform automatic PCI DMA operations
+ between the AST2XXX (acting as a BMC) and a host processor.
+
endmenu
diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile
index b64be47f2b1f..977b046dfb73 100644
--- a/drivers/soc/aspeed/Makefile
+++ b/drivers/soc/aspeed/Makefile
@@ -2,3 +2,4 @@
obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o
obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o
+obj-$(CONFIG_ASPEED_XDMA) += aspeed-xdma.o
diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
new file mode 100644
index 000000000000..bc746b262de7
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-xdma.c
@@ -0,0 +1,840 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright IBM Corp 2019
+
+#include <linux/aspeed-xdma.h>
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/fs.h>
+#include <linux/genalloc.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_device.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#define DEVICE_NAME "aspeed-xdma"
+
+#define SCU_AST2600_MISC_CTRL 0x0c0
+#define SCU_AST2600_MISC_CTRL_XDMA_BMC BIT(8)
+
+#define SCU_AST2500_PCIE_CONF 0x180
+#define SCU_AST2600_PCIE_CONF 0xc20
+#define SCU_PCIE_CONF_VGA_EN BIT(0)
+#define SCU_PCIE_CONF_VGA_EN_MMIO BIT(1)
+#define SCU_PCIE_CONF_VGA_EN_LPC BIT(2)
+#define SCU_PCIE_CONF_VGA_EN_MSI BIT(3)
+#define SCU_PCIE_CONF_VGA_EN_MCTP BIT(4)
+#define SCU_PCIE_CONF_VGA_EN_IRQ BIT(5)
+#define SCU_PCIE_CONF_VGA_EN_DMA BIT(6)
+#define SCU_PCIE_CONF_BMC_EN BIT(8)
+#define SCU_PCIE_CONF_BMC_EN_MMIO BIT(9)
+#define SCU_PCIE_CONF_BMC_EN_MSI BIT(11)
+#define SCU_PCIE_CONF_BMC_EN_MCTP BIT(12)
+#define SCU_PCIE_CONF_BMC_EN_IRQ BIT(13)
+#define SCU_PCIE_CONF_BMC_EN_DMA BIT(14)
+
+#define SCU_AST2500_BMC_CLASS_REV 0x19c
+#define SCU_AST2600_BMC_CLASS_REV 0xc68
+#define SCU_BMC_CLASS_REV_XDMA 0xff000001
+
+#define XDMA_CMDQ_SIZE PAGE_SIZE
+#define XDMA_NUM_CMDS \
+ (XDMA_CMDQ_SIZE / sizeof(struct aspeed_xdma_cmd))
+
+/* Aspeed specification requires 100us after disabling the reset */
+#define XDMA_ENGINE_SETUP_TIME_MAX_US 1000
+#define XDMA_ENGINE_SETUP_TIME_MIN_US 100
+
+#define XDMA_CMD_AST2500_PITCH_SHIFT 3
+#define XDMA_CMD_AST2500_PITCH_BMC GENMASK_ULL(62, 51)
+#define XDMA_CMD_AST2500_PITCH_HOST GENMASK_ULL(46, 35)
+#define XDMA_CMD_AST2500_PITCH_UPSTREAM BIT_ULL(31)
+#define XDMA_CMD_AST2500_PITCH_ADDR GENMASK_ULL(29, 4)
+#define XDMA_CMD_AST2500_PITCH_ID BIT_ULL(0)
+#define XDMA_CMD_AST2500_CMD_IRQ_EN BIT_ULL(31)
+#define XDMA_CMD_AST2500_CMD_LINE_NO GENMASK_ULL(27, 16)
+#define XDMA_CMD_AST2500_CMD_IRQ_BMC BIT_ULL(15)
+#define XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT 4
+#define XDMA_CMD_AST2500_CMD_LINE_SIZE \
+ GENMASK_ULL(14, XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT)
+#define XDMA_CMD_AST2500_CMD_ID BIT_ULL(1)
+
+#define XDMA_CMD_AST2600_PITCH_BMC GENMASK_ULL(62, 48)
+#define XDMA_CMD_AST2600_PITCH_HOST GENMASK_ULL(46, 32)
+#define XDMA_CMD_AST2600_PITCH_ADDR GENMASK_ULL(30, 0)
+#define XDMA_CMD_AST2600_CMD_64_EN BIT_ULL(40)
+#define XDMA_CMD_AST2600_CMD_IRQ_BMC BIT_ULL(37)
+#define XDMA_CMD_AST2600_CMD_IRQ_HOST BIT_ULL(36)
+#define XDMA_CMD_AST2600_CMD_UPSTREAM BIT_ULL(32)
+#define XDMA_CMD_AST2600_CMD_LINE_NO GENMASK_ULL(27, 16)
+#define XDMA_CMD_AST2600_CMD_LINE_SIZE GENMASK_ULL(14, 0)
+#define XDMA_CMD_AST2600_CMD_MULTILINE_SIZE GENMASK_ULL(14, 12)
+
+#define XDMA_AST2500_QUEUE_ENTRY_SIZE 4
+#define XDMA_AST2500_HOST_CMDQ_ADDR0 0x00
+#define XDMA_AST2500_HOST_CMDQ_ENDP 0x04
+#define XDMA_AST2500_HOST_CMDQ_WRITEP 0x08
+#define XDMA_AST2500_HOST_CMDQ_READP 0x0c
+#define XDMA_AST2500_BMC_CMDQ_ADDR 0x10
+#define XDMA_AST2500_BMC_CMDQ_ENDP 0x14
+#define XDMA_AST2500_BMC_CMDQ_WRITEP 0x18
+#define XDMA_AST2500_BMC_CMDQ_READP 0x1c
+#define XDMA_BMC_CMDQ_READP_RESET 0xee882266
+#define XDMA_AST2500_CTRL 0x20
+#define XDMA_AST2500_CTRL_US_COMP BIT(4)
+#define XDMA_AST2500_CTRL_DS_COMP BIT(5)
+#define XDMA_AST2500_CTRL_DS_DIRTY BIT(6)
+#define XDMA_AST2500_CTRL_DS_SIZE_256 BIT(17)
+#define XDMA_AST2500_CTRL_DS_TIMEOUT BIT(28)
+#define XDMA_AST2500_CTRL_DS_CHECK_ID BIT(29)
+#define XDMA_AST2500_STATUS 0x24
+#define XDMA_AST2500_STATUS_US_COMP BIT(4)
+#define XDMA_AST2500_STATUS_DS_COMP BIT(5)
+#define XDMA_AST2500_STATUS_DS_DIRTY BIT(6)
+#define XDMA_AST2500_INPRG_DS_CMD1 0x38
+#define XDMA_AST2500_INPRG_DS_CMD2 0x3c
+#define XDMA_AST2500_INPRG_US_CMD00 0x40
+#define XDMA_AST2500_INPRG_US_CMD01 0x44
+#define XDMA_AST2500_INPRG_US_CMD10 0x48
+#define XDMA_AST2500_INPRG_US_CMD11 0x4c
+#define XDMA_AST2500_INPRG_US_CMD20 0x50
+#define XDMA_AST2500_INPRG_US_CMD21 0x54
+#define XDMA_AST2500_HOST_CMDQ_ADDR1 0x60
+#define XDMA_AST2500_VGA_CMDQ_ADDR0 0x64
+#define XDMA_AST2500_VGA_CMDQ_ENDP 0x68
+#define XDMA_AST2500_VGA_CMDQ_WRITEP 0x6c
+#define XDMA_AST2500_VGA_CMDQ_READP 0x70
+#define XDMA_AST2500_VGA_CMD_STATUS 0x74
+#define XDMA_AST2500_VGA_CMDQ_ADDR1 0x78
+
+#define XDMA_AST2600_QUEUE_ENTRY_SIZE 2
+#define XDMA_AST2600_HOST_CMDQ_ADDR0 0x00
+#define XDMA_AST2600_HOST_CMDQ_ADDR1 0x04
+#define XDMA_AST2600_HOST_CMDQ_ENDP 0x08
+#define XDMA_AST2600_HOST_CMDQ_WRITEP 0x0c
+#define XDMA_AST2600_HOST_CMDQ_READP 0x10
+#define XDMA_AST2600_BMC_CMDQ_ADDR 0x14
+#define XDMA_AST2600_BMC_CMDQ_ENDP 0x18
+#define XDMA_AST2600_BMC_CMDQ_WRITEP 0x1c
+#define XDMA_AST2600_BMC_CMDQ_READP 0x20
+#define XDMA_AST2600_VGA_CMDQ_ADDR0 0x24
+#define XDMA_AST2600_VGA_CMDQ_ADDR1 0x28
+#define XDMA_AST2600_VGA_CMDQ_ENDP 0x2c
+#define XDMA_AST2600_VGA_CMDQ_WRITEP 0x30
+#define XDMA_AST2600_VGA_CMDQ_READP 0x34
+#define XDMA_AST2600_CTRL 0x38
+#define XDMA_AST2600_CTRL_US_COMP BIT(16)
+#define XDMA_AST2600_CTRL_DS_COMP BIT(17)
+#define XDMA_AST2600_CTRL_DS_DIRTY BIT(18)
+#define XDMA_AST2600_CTRL_DS_SIZE_256 BIT(20)
+#define XDMA_AST2600_STATUS 0x3c
+#define XDMA_AST2600_STATUS_US_COMP BIT(16)
+#define XDMA_AST2600_STATUS_DS_COMP BIT(17)
+#define XDMA_AST2600_STATUS_DS_DIRTY BIT(18)
+#define XDMA_AST2600_INPRG_DS_CMD00 0x40
+#define XDMA_AST2600_INPRG_DS_CMD01 0x44
+#define XDMA_AST2600_INPRG_DS_CMD10 0x48
+#define XDMA_AST2600_INPRG_DS_CMD11 0x4c
+#define XDMA_AST2600_INPRG_DS_CMD20 0x50
+#define XDMA_AST2600_INPRG_DS_CMD21 0x54
+#define XDMA_AST2600_INPRG_US_CMD00 0x60
+#define XDMA_AST2600_INPRG_US_CMD01 0x64
+#define XDMA_AST2600_INPRG_US_CMD10 0x68
+#define XDMA_AST2600_INPRG_US_CMD11 0x6c
+#define XDMA_AST2600_INPRG_US_CMD20 0x70
+#define XDMA_AST2600_INPRG_US_CMD21 0x74
+
+struct aspeed_xdma_cmd {
+ u64 host_addr;
+ u64 pitch;
+ u64 cmd;
+ u64 reserved;
+};
+
+struct aspeed_xdma_regs {
+ u8 bmc_cmdq_addr;
+ u8 bmc_cmdq_endp;
+ u8 bmc_cmdq_writep;
+ u8 bmc_cmdq_readp;
+ u8 control;
+ u8 status;
+};
+
+struct aspeed_xdma_status_bits {
+ u32 us_comp;
+ u32 ds_comp;
+ u32 ds_dirty;
+};
+
+struct aspeed_xdma;
+
+struct aspeed_xdma_chip {
+ u32 control;
+ u32 scu_bmc_class;
+ u32 scu_misc_ctrl;
+ u32 scu_pcie_conf;
+ unsigned int queue_entry_size;
+ struct aspeed_xdma_regs regs;
+ struct aspeed_xdma_status_bits status_bits;
+ unsigned int (*set_cmd)(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_cmd cmds[2],
+ struct aspeed_xdma_op *op, u32 bmc_addr);
+};
+
+struct aspeed_xdma_client;
+
+struct aspeed_xdma {
+ const struct aspeed_xdma_chip *chip;
+
+ struct device *dev;
+ void __iomem *base;
+ struct clk *clock;
+ struct reset_control *reset;
+ struct reset_control *reset_rc;
+
+ /* client_lock protects error and in_progress of the client */
+ spinlock_t client_lock;
+ struct aspeed_xdma_client *current_client;
+
+ /* start_lock protects cmd_idx, cmdq, and the state of the engine */
+ struct mutex start_lock;
+ struct aspeed_xdma_cmd *cmdq;
+ bool upstream;
+ unsigned int cmd_idx;
+
+ /* reset_lock protects in_reset and the reset state of the engine */
+ spinlock_t reset_lock;
+ bool in_reset;
+
+ wait_queue_head_t wait;
+ struct work_struct reset_work;
+
+ u32 mem_phys;
+ u32 mem_size;
+ void __iomem *mem_virt;
+ dma_addr_t cmdq_phys;
+ struct gen_pool *pool;
+};
+
+struct aspeed_xdma_client {
+ struct aspeed_xdma *ctx;
+
+ bool error;
+ bool in_progress;
+ void *virt;
+ dma_addr_t phys;
+ u32 size;
+};
+
+static u32 aspeed_xdma_readl(struct aspeed_xdma *ctx, u8 reg)
+{
+ u32 v = readl(ctx->base + reg);
+
+ dev_dbg(ctx->dev, "read %02x[%08x]\n", reg, v);
+ return v;
+}
+
+static void aspeed_xdma_writel(struct aspeed_xdma *ctx, u8 reg, u32 val)
+{
+ writel(val, ctx->base + reg);
+ dev_dbg(ctx->dev, "write %02x[%08x]\n", reg, val);
+}
+
+static void aspeed_xdma_init_eng(struct aspeed_xdma *ctx)
+{
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_endp,
+ ctx->chip->queue_entry_size * XDMA_NUM_CMDS);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_readp,
+ XDMA_BMC_CMDQ_READP_RESET);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep, 0);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.control, ctx->chip->control);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_addr, ctx->cmdq_phys);
+
+ ctx->cmd_idx = 0;
+}
+
+static unsigned int aspeed_xdma_ast2500_set_cmd(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_cmd cmds[2],
+ struct aspeed_xdma_op *op,
+ u32 bmc_addr)
+{
+ unsigned int rc = 1;
+ unsigned int pitch = 1;
+ unsigned int line_no = 1;
+ unsigned int line_size = op->len >>
+ XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+ u64 cmd = XDMA_CMD_AST2500_CMD_IRQ_EN | XDMA_CMD_AST2500_CMD_IRQ_BMC |
+ XDMA_CMD_AST2500_CMD_ID;
+ u64 cmd_pitch = (op->direction ? XDMA_CMD_AST2500_PITCH_UPSTREAM : 0) |
+ XDMA_CMD_AST2500_PITCH_ID;
+
+ dev_dbg(ctx->dev, "xdma %s ast2500: bmc[%08x] len[%08x] host[%08x]\n",
+ op->direction ? "upstream" : "downstream", bmc_addr, op->len,
+ (u32)op->host_addr);
+
+ if (op->len > XDMA_CMD_AST2500_CMD_LINE_SIZE) {
+ unsigned int rem;
+ unsigned int total;
+
+ line_no = op->len / XDMA_CMD_AST2500_CMD_LINE_SIZE;
+ total = XDMA_CMD_AST2500_CMD_LINE_SIZE * line_no;
+ rem = (op->len - total) >>
+ XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+ line_size = XDMA_CMD_AST2500_CMD_LINE_SIZE;
+ pitch = line_size >> XDMA_CMD_AST2500_PITCH_SHIFT;
+ line_size >>= XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+
+ if (rem) {
+ u32 rbmc = bmc_addr + total;
+
+ cmds[1].host_addr = op->host_addr + (u64)total;
+ cmds[1].pitch = cmd_pitch |
+ ((u64)rbmc & XDMA_CMD_AST2500_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, 1) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, 1);
+ cmds[1].cmd = cmd |
+ FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, 1) |
+ FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE,
+ rem);
+ cmds[1].reserved = 0ULL;
+
+ print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
+ 16, 1, &cmds[1], sizeof(*cmds),
+ true);
+
+ cmd &= ~(XDMA_CMD_AST2500_CMD_IRQ_EN |
+ XDMA_CMD_AST2500_CMD_IRQ_BMC);
+
+ rc++;
+ }
+ }
+
+ cmds[0].host_addr = op->host_addr;
+ cmds[0].pitch = cmd_pitch |
+ ((u64)bmc_addr & XDMA_CMD_AST2500_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, pitch) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, pitch);
+ cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, line_no) |
+ FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE, line_size);
+ cmds[0].reserved = 0ULL;
+
+ print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds,
+ sizeof(*cmds), true);
+
+ return rc;
+}
+
+static unsigned int aspeed_xdma_ast2600_set_cmd(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_cmd cmds[2],
+ struct aspeed_xdma_op *op,
+ u32 bmc_addr)
+{
+ unsigned int rc = 1;
+ unsigned int pitch = 1;
+ unsigned int line_no = 1;
+ unsigned int line_size = op->len;
+ u64 cmd = XDMA_CMD_AST2600_CMD_IRQ_BMC |
+ (op->direction ? XDMA_CMD_AST2600_CMD_UPSTREAM : 0);
+
+ if (op->host_addr & 0xffffffff00000000ULL ||
+ (op->host_addr + (u64)op->len) & 0xffffffff00000000ULL)
+ cmd |= XDMA_CMD_AST2600_CMD_64_EN;
+
+ dev_dbg(ctx->dev, "xdma %s ast2600: bmc[%08x] len[%08x] "
+ "host[%016llx]\n", op->direction ? "upstream" : "downstream",
+ bmc_addr, op->len, op->host_addr);
+
+ if (op->len > XDMA_CMD_AST2600_CMD_LINE_SIZE) {
+ unsigned int rem;
+ unsigned int total;
+
+ line_no = op->len / XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
+ total = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE * line_no;
+ rem = op->len - total;
+ line_size = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
+ pitch = line_size;
+
+ if (rem) {
+ u32 rbmc = bmc_addr + total;
+
+ cmds[1].host_addr = op->host_addr + (u64)total;
+ cmds[1].pitch =
+ ((u64)rbmc & XDMA_CMD_AST2600_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, 1) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, 1);
+ cmds[1].cmd = cmd |
+ FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, 1) |
+ FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE,
+ rem);
+ cmds[1].reserved = 0ULL;
+
+ print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
+ 16, 1, &cmds[1], sizeof(*cmds),
+ true);
+
+ cmd &= ~XDMA_CMD_AST2600_CMD_IRQ_BMC;
+
+ rc++;
+ }
+ }
+
+ cmds[0].host_addr = op->host_addr;
+ cmds[0].pitch = ((u64)bmc_addr & XDMA_CMD_AST2600_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, pitch) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, pitch);
+ cmds[0].cmd = cmd | FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, line_no) |
+ FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE, line_size);
+ cmds[0].reserved = 0ULL;
+
+ print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, cmds,
+ sizeof(*cmds), true);
+
+ return rc;
+}
+
+static void aspeed_xdma_start(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_op *op, u32 bmc_addr,
+ struct aspeed_xdma_client *client)
+{
+ unsigned int i;
+ unsigned long flags;
+ struct aspeed_xdma_cmd cmds[2];
+ unsigned int rc = ctx->chip->set_cmd(ctx, cmds, op, bmc_addr);
+
+ mutex_lock(&ctx->start_lock);
+
+ for (i = 0; i < rc; ++i) {
+ memcpy(&ctx->cmdq[ctx->cmd_idx], &cmds[i],
+ sizeof(struct aspeed_xdma_cmd));
+ ctx->cmd_idx = (ctx->cmd_idx + 1) % XDMA_NUM_CMDS;
+ }
+
+ ctx->upstream = !!op->direction;
+
+ spin_lock_irqsave(&ctx->client_lock, flags);
+
+ client->error = false;
+ client->in_progress = true;
+ ctx->current_client = client;
+
+ spin_unlock_irqrestore(&ctx->client_lock, flags);
+
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep,
+ ctx->cmd_idx * ctx->chip->queue_entry_size);
+
+ mutex_unlock(&ctx->start_lock);
+}
+
+static void aspeed_xdma_done(struct aspeed_xdma *ctx, bool error)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctx->client_lock, flags);
+
+ if (ctx->current_client) {
+ ctx->current_client->error = error;
+ ctx->current_client->in_progress = false;
+ ctx->current_client = NULL;
+ }
+
+ spin_unlock_irqrestore(&ctx->client_lock, flags);
+
+ wake_up_interruptible_all(&ctx->wait);
+}
+
+static irqreturn_t aspeed_xdma_irq(int irq, void *arg)
+{
+ struct aspeed_xdma *ctx = arg;
+ u32 status = aspeed_xdma_readl(ctx, ctx->chip->regs.status);
+
+ if (status & ctx->chip->status_bits.ds_dirty) {
+ aspeed_xdma_done(ctx, true);
+ } else {
+ if (status & ctx->chip->status_bits.us_comp) {
+ if (ctx->upstream)
+ aspeed_xdma_done(ctx, false);
+ }
+
+ if (status & ctx->chip->status_bits.ds_comp) {
+ if (!ctx->upstream)
+ aspeed_xdma_done(ctx, false);
+ }
+ }
+
+ aspeed_xdma_writel(ctx, ctx->chip->regs.status, status);
+
+ return IRQ_HANDLED;
+}
+
+static void aspeed_xdma_reset(struct aspeed_xdma *ctx)
+{
+ unsigned long flags;
+
+ reset_control_assert(ctx->reset);
+ usleep_range(XDMA_ENGINE_SETUP_TIME_MIN_US,
+ XDMA_ENGINE_SETUP_TIME_MAX_US);
+ reset_control_deassert(ctx->reset);
+ usleep_range(XDMA_ENGINE_SETUP_TIME_MIN_US,
+ XDMA_ENGINE_SETUP_TIME_MAX_US);
+
+ aspeed_xdma_init_eng(ctx);
+
+ spin_lock_irqsave(&ctx->reset_lock, flags);
+ ctx->in_reset = false;
+ spin_unlock_irqrestore(&ctx->reset_lock, flags);
+
+ aspeed_xdma_done(ctx, true);
+}
+
+static void aspeed_xdma_reset_work(struct work_struct *work)
+{
+ struct aspeed_xdma *ctx = container_of(work, struct aspeed_xdma,
+ reset_work);
+
+ /*
+ * Lock to make sure operations aren't started while the engine is
+ * in reset.
+ */
+ mutex_lock(&ctx->start_lock);
+
+ aspeed_xdma_reset(ctx);
+
+ mutex_unlock(&ctx->start_lock);
+}
+
+static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg)
+{
+ unsigned long flags;
+ struct aspeed_xdma *ctx = arg;
+
+ dev_dbg(ctx->dev, "PCI-E reset requested.\n");
+
+ spin_lock_irqsave(&ctx->reset_lock, flags);
+ if (ctx->in_reset) {
+ spin_unlock_irqrestore(&ctx->reset_lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ ctx->in_reset = true;
+ spin_unlock_irqrestore(&ctx->reset_lock, flags);
+
+ schedule_work(&ctx->reset_work);
+ return IRQ_HANDLED;
+}
+
+static int aspeed_xdma_init_scu(struct aspeed_xdma *ctx, struct device *dev)
+{
+ struct regmap *scu = syscon_regmap_lookup_by_phandle(dev->of_node,
+ "aspeed,scu");
+
+ if (!IS_ERR(scu)) {
+ u32 selection;
+ bool pcie_device_bmc = true;
+ const u32 bmc = SCU_PCIE_CONF_BMC_EN |
+ SCU_PCIE_CONF_BMC_EN_MSI | SCU_PCIE_CONF_BMC_EN_IRQ |
+ SCU_PCIE_CONF_BMC_EN_DMA;
+ const u32 vga = SCU_PCIE_CONF_VGA_EN |
+ SCU_PCIE_CONF_VGA_EN_MSI | SCU_PCIE_CONF_VGA_EN_IRQ |
+ SCU_PCIE_CONF_VGA_EN_DMA;
+ const char *pcie = NULL;
+
+ if (!of_property_read_string(dev->of_node, "pcie-device",
+ &pcie)) {
+ if (!strcmp(pcie, "vga")) {
+ pcie_device_bmc = false;
+ } else if (strcmp(pcie, "bmc")) {
+ dev_err(dev,
+ "Invalid pcie-device property %s.\n",
+ pcie);
+ return -EINVAL;
+ }
+ }
+
+ if (pcie_device_bmc) {
+ selection = bmc;
+ regmap_write(scu, ctx->chip->scu_bmc_class,
+ SCU_BMC_CLASS_REV_XDMA);
+ } else {
+ selection = vga;
+ }
+
+ regmap_update_bits(scu, ctx->chip->scu_pcie_conf, bmc | vga,
+ selection);
+
+ if (ctx->chip->scu_misc_ctrl)
+ regmap_update_bits(scu, ctx->chip->scu_misc_ctrl,
+ SCU_AST2600_MISC_CTRL_XDMA_BMC,
+ SCU_AST2600_MISC_CTRL_XDMA_BMC);
+ } else {
+ dev_warn(dev, "Unable to configure PCIe: %ld; continuing.\n",
+ PTR_ERR(scu));
+ }
+
+ return 0;
+}
+
+static int aspeed_xdma_probe(struct platform_device *pdev)
+{
+ int rc;
+ int irq;
+ int pcie_irq;
+ struct aspeed_xdma *ctx;
+ struct reserved_mem *mem;
+ struct device *dev = &pdev->dev;
+ struct device_node *memory_region;
+ const void *md = of_device_get_match_data(dev);
+
+ if (!md)
+ return -ENODEV;
+
+ ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->chip = md;
+ ctx->dev = dev;
+ platform_set_drvdata(pdev, ctx);
+ mutex_init(&ctx->start_lock);
+ INIT_WORK(&ctx->reset_work, aspeed_xdma_reset_work);
+ spin_lock_init(&ctx->client_lock);
+ spin_lock_init(&ctx->reset_lock);
+ init_waitqueue_head(&ctx->wait);
+
+ ctx->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ctx->base)) {
+ dev_err(dev, "Failed to map registers.\n");
+ return PTR_ERR(ctx->base);
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(dev, "Failed to find IRQ.\n");
+ return irq;
+ }
+
+ rc = devm_request_irq(dev, irq, aspeed_xdma_irq, 0, DEVICE_NAME, ctx);
+ if (rc < 0) {
+ dev_err(dev, "Failed to request IRQ %d.\n", irq);
+ return rc;
+ }
+
+ ctx->clock = devm_clk_get(dev, NULL);
+ if (IS_ERR(ctx->clock)) {
+ dev_err(dev, "Failed to request clock.\n");
+ return PTR_ERR(ctx->clock);
+ }
+
+ ctx->reset = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(ctx->reset)) {
+ dev_err(dev, "Failed to request reset control.\n");
+ return PTR_ERR(ctx->reset);
+ }
+
+ ctx->reset_rc = devm_reset_control_get_exclusive(dev, "rc");
+ if (IS_ERR(ctx->reset_rc)) {
+ dev_dbg(dev, "Failed to request reset RC control.\n");
+ ctx->reset_rc = NULL;
+ }
+
+ ctx->pool = devm_gen_pool_create(dev, ilog2(PAGE_SIZE), -1, NULL);
+ if (!ctx->pool) {
+ dev_err(dev, "Failed to setup genalloc pool.\n");
+ return -ENOMEM;
+ }
+
+ memory_region = of_parse_phandle(dev->of_node, "memory-region", 0);
+ if (!memory_region) {
+ dev_err(dev, "Failed to find memory-region.\n");
+ return -ENOMEM;
+ }
+
+ mem = of_reserved_mem_lookup(memory_region);
+ of_node_put(memory_region);
+ if (!mem) {
+ dev_err(dev, "Failed to find reserved memory.\n");
+ return -ENOMEM;
+ }
+
+ ctx->mem_phys = mem->base;
+ ctx->mem_size = mem->size;
+
+ ctx->mem_virt = devm_ioremap(dev, ctx->mem_phys, ctx->mem_size);
+ if (!ctx->mem_virt) {
+ dev_err(dev, "Failed to map memory space.\n");
+ return -ENOMEM;
+ }
+
+ rc = gen_pool_add_virt(ctx->pool, (unsigned long)ctx->mem_virt,
+ ctx->mem_phys, ctx->mem_size, -1);
+ if (rc) {
+ dev_err(ctx->dev, "Failed to add memory to genalloc pool.\n");
+ return rc;
+ }
+
+ rc = aspeed_xdma_init_scu(ctx, dev);
+ if (rc)
+ return rc;
+
+ rc = clk_prepare_enable(ctx->clock);
+ if (rc) {
+ dev_err(dev, "Failed to enable the clock.\n");
+ return rc;
+ }
+
+ if (ctx->reset_rc) {
+ rc = reset_control_deassert(ctx->reset_rc);
+ if (rc) {
+ dev_err(dev, "Failed to clear the RC reset.\n");
+ goto err_reset_rc;
+ }
+ usleep_range(XDMA_ENGINE_SETUP_TIME_MIN_US,
+ XDMA_ENGINE_SETUP_TIME_MAX_US);
+ }
+
+ rc = reset_control_deassert(ctx->reset);
+ if (rc) {
+ dev_err(dev, "Failed to clear the reset.\n");
+ goto err_reset;
+ }
+ usleep_range(XDMA_ENGINE_SETUP_TIME_MIN_US,
+ XDMA_ENGINE_SETUP_TIME_MAX_US);
+
+ ctx->cmdq = gen_pool_dma_alloc(ctx->pool, XDMA_CMDQ_SIZE,
+ &ctx->cmdq_phys);
+ if (!ctx->cmdq) {
+ dev_err(ctx->dev, "Failed to genalloc cmdq.\n");
+ rc = -ENOMEM;
+ goto err;
+ }
+
+ aspeed_xdma_init_eng(ctx);
+
+ /*
+ * This interrupt could fire immediately so only request it once the
+ * engine and driver are initialized.
+ */
+ pcie_irq = platform_get_irq(pdev, 1);
+ if (pcie_irq < 0) {
+ dev_warn(dev, "Failed to find PCI-E IRQ.\n");
+ } else {
+ rc = devm_request_irq(dev, pcie_irq, aspeed_xdma_pcie_irq,
+ IRQF_SHARED, DEVICE_NAME, ctx);
+ if (rc < 0)
+ dev_warn(dev, "Failed to request PCI-E IRQ %d.\n", rc);
+ }
+
+ return 0;
+
+err:
+ reset_control_assert(ctx->reset);
+err_reset:
+ if (ctx->reset_rc)
+ reset_control_assert(ctx->reset_rc);
+err_reset_rc:
+ clk_disable_unprepare(ctx->clock);
+ return rc;
+}
+
+static int aspeed_xdma_remove(struct platform_device *pdev)
+{
+ struct aspeed_xdma *ctx = platform_get_drvdata(pdev);
+
+ gen_pool_free(ctx->pool, (unsigned long)ctx->cmdq, XDMA_CMDQ_SIZE);
+
+ reset_control_assert(ctx->reset);
+ if (ctx->reset_rc)
+ reset_control_assert(ctx->reset_rc);
+ clk_disable_unprepare(ctx->clock);
+
+ return 0;
+}
+
+static const struct aspeed_xdma_chip aspeed_ast2500_xdma_chip = {
+ .control = XDMA_AST2500_CTRL_US_COMP | XDMA_AST2500_CTRL_DS_COMP |
+ XDMA_AST2500_CTRL_DS_DIRTY | XDMA_AST2500_CTRL_DS_SIZE_256 |
+ XDMA_AST2500_CTRL_DS_TIMEOUT | XDMA_AST2500_CTRL_DS_CHECK_ID,
+ .scu_bmc_class = SCU_AST2500_BMC_CLASS_REV,
+ .scu_misc_ctrl = 0,
+ .scu_pcie_conf = SCU_AST2500_PCIE_CONF,
+ .queue_entry_size = XDMA_AST2500_QUEUE_ENTRY_SIZE,
+ .regs = {
+ .bmc_cmdq_addr = XDMA_AST2500_BMC_CMDQ_ADDR,
+ .bmc_cmdq_endp = XDMA_AST2500_BMC_CMDQ_ENDP,
+ .bmc_cmdq_writep = XDMA_AST2500_BMC_CMDQ_WRITEP,
+ .bmc_cmdq_readp = XDMA_AST2500_BMC_CMDQ_READP,
+ .control = XDMA_AST2500_CTRL,
+ .status = XDMA_AST2500_STATUS,
+ },
+ .status_bits = {
+ .us_comp = XDMA_AST2500_STATUS_US_COMP,
+ .ds_comp = XDMA_AST2500_STATUS_DS_COMP,
+ .ds_dirty = XDMA_AST2500_STATUS_DS_DIRTY,
+ },
+ .set_cmd = aspeed_xdma_ast2500_set_cmd,
+};
+
+static const struct aspeed_xdma_chip aspeed_ast2600_xdma_chip = {
+ .control = XDMA_AST2600_CTRL_US_COMP | XDMA_AST2600_CTRL_DS_COMP |
+ XDMA_AST2600_CTRL_DS_DIRTY | XDMA_AST2600_CTRL_DS_SIZE_256,
+ .scu_bmc_class = SCU_AST2600_BMC_CLASS_REV,
+ .scu_misc_ctrl = SCU_AST2600_MISC_CTRL,
+ .scu_pcie_conf = SCU_AST2600_PCIE_CONF,
+ .queue_entry_size = XDMA_AST2600_QUEUE_ENTRY_SIZE,
+ .regs = {
+ .bmc_cmdq_addr = XDMA_AST2600_BMC_CMDQ_ADDR,
+ .bmc_cmdq_endp = XDMA_AST2600_BMC_CMDQ_ENDP,
+ .bmc_cmdq_writep = XDMA_AST2600_BMC_CMDQ_WRITEP,
+ .bmc_cmdq_readp = XDMA_AST2600_BMC_CMDQ_READP,
+ .control = XDMA_AST2600_CTRL,
+ .status = XDMA_AST2600_STATUS,
+ },
+ .status_bits = {
+ .us_comp = XDMA_AST2600_STATUS_US_COMP,
+ .ds_comp = XDMA_AST2600_STATUS_DS_COMP,
+ .ds_dirty = XDMA_AST2600_STATUS_DS_DIRTY,
+ },
+ .set_cmd = aspeed_xdma_ast2600_set_cmd,
+};
+
+static const struct of_device_id aspeed_xdma_match[] = {
+ {
+ .compatible = "aspeed,ast2500-xdma",
+ .data = &aspeed_ast2500_xdma_chip,
+ },
+ {
+ .compatible = "aspeed,ast2600-xdma",
+ .data = &aspeed_ast2600_xdma_chip,
+ },
+ { },
+};
+
+static struct platform_driver aspeed_xdma_driver = {
+ .probe = aspeed_xdma_probe,
+ .remove = aspeed_xdma_remove,
+ .driver = {
+ .name = DEVICE_NAME,
+ .of_match_table = aspeed_xdma_match,
+ },
+};
+
+module_platform_driver(aspeed_xdma_driver);
+
+MODULE_AUTHOR("Eddie James");
+MODULE_DESCRIPTION("Aspeed XDMA Engine Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/uapi/linux/aspeed-xdma.h b/include/uapi/linux/aspeed-xdma.h
new file mode 100644
index 000000000000..2efaa6067c39
--- /dev/null
+++ b/include/uapi/linux/aspeed-xdma.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/* Copyright IBM Corp 2019 */
+
+#ifndef _UAPI_LINUX_ASPEED_XDMA_H_
+#define _UAPI_LINUX_ASPEED_XDMA_H_
+
+#include <linux/types.h>
+
+/*
+ * aspeed_xdma_direction
+ *
+ * ASPEED_XDMA_DIRECTION_DOWNSTREAM: transfers data from the host to the BMC
+ *
+ * ASPEED_XDMA_DIRECTION_UPSTREAM: transfers data from the BMC to the host
+ */
+enum aspeed_xdma_direction {
+ ASPEED_XDMA_DIRECTION_DOWNSTREAM = 0,
+ ASPEED_XDMA_DIRECTION_UPSTREAM,
+};
+
+/*
+ * aspeed_xdma_op
+ *
+ * host_addr: the DMA address on the host side, typically configured by PCI
+ * subsystem
+ *
+ * len: the size of the transfer in bytes
+ *
+ * direction: an enumerator indicating the direction of the DMA operation; see
+ * enum aspeed_xdma_direction
+ */
+struct aspeed_xdma_op {
+ __u64 host_addr;
+ __u32 len;
+ __u32 direction;
+};
+
+#endif /* _UAPI_LINUX_ASPEED_XDMA_H_ */
--
2.24.0