[PATCH 2/3] fsi: Add ast2600 master driver
Joel Stanley
joel at jms.id.au
Fri Nov 1 22:29:04 AEDT 2019
The ast2600 BMC has a pair of FSI masters in it, behind an AHB to OPB
bridge.
Signed-off-by: Joel Stanley <joel at jms.id.au>
---
drivers/fsi/Kconfig | 6 +
drivers/fsi/Makefile | 1 +
drivers/fsi/fsi-master-aspeed.c | 528 ++++++++++++++++++++++++++++++++
3 files changed, 535 insertions(+)
create mode 100644 drivers/fsi/fsi-master-aspeed.c
diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
index c612db7a914a..12e8c4a04fb1 100644
--- a/drivers/fsi/Kconfig
+++ b/drivers/fsi/Kconfig
@@ -53,6 +53,12 @@ config FSI_MASTER_AST_CF
lines driven by the internal ColdFire coprocessor. This requires
the corresponding machine specific ColdFire firmware to be available.
+config FSI_MASTER_ASPEED
+ tristate "FSI ASPEED master"
+ help
+ This option enables a FSI master that is present behind an OPB bridge
+ in the AST2600.
+
config FSI_SCOM
tristate "SCOM FSI client device driver"
---help---
diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
index e4a2ff043c32..da218a1ad8e1 100644
--- a/drivers/fsi/Makefile
+++ b/drivers/fsi/Makefile
@@ -2,6 +2,7 @@
obj-$(CONFIG_FSI) += fsi-core.o
obj-$(CONFIG_FSI_MASTER_HUB) += fsi-master-hub.o
+obj-$(CONFIG_FSI_MASTER_ASPEED) += fsi-master-aspeed.o
obj-$(CONFIG_FSI_MASTER_GPIO) += fsi-master-gpio.o
obj-$(CONFIG_FSI_MASTER_AST_CF) += fsi-master-ast-cf.o
obj-$(CONFIG_FSI_SCOM) += fsi-scom.o
diff --git a/drivers/fsi/fsi-master-aspeed.c b/drivers/fsi/fsi-master-aspeed.c
new file mode 100644
index 000000000000..5bb7a778075e
--- /dev/null
+++ b/drivers/fsi/fsi-master-aspeed.c
@@ -0,0 +1,528 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright (C) IBM Corporation 2018
+// FSI master driver for AST2600
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/fsi.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+#include <linux/iopoll.h>
+
+#include "fsi-master.h"
+
+struct fsi_master_aspeed {
+ struct fsi_master master;
+ struct device *dev;
+ void __iomem *base;
+ struct clk *clk;
+};
+
+#define to_fsi_master_aspeed(m) \
+ container_of(m, struct fsi_master_aspeed, master)
+
+/* Control register (size 0x400) */
+static const u32 ctrl_base = 0x80000000;
+
+static const u32 fsi_base = 0xa0000000;
+
+#define OPB_FSI_VER 0x00
+#define OPB_TRIGGER 0x04
+#define OPB_CTRL_BASE 0x08
+#define OPB_FSI_BASE 0x0c
+#define OPB_CLK_SYNC 0x3c
+#define OPB_IRQ_CLEAR 0x40
+#define OPB_IRQ_MASK 0x44
+#define OPB_IRQ_STATUS 0x48
+
+#define OPB0_SELECT 0x10
+#define OPB0_RW 0x14
+#define OPB0_XFER_SIZE 0x18
+#define OPB0_FSI_ADDR 0x1c
+#define OPB0_FSI_DATA_W 0x20
+#define OPB0_STATUS 0x80
+#define STATUS_HALFWORD_ACK BIT(0)
+#define STATUS_FULLWORD_ACK BIT(1)
+#define STATUS_ERR_ACK BIT(2)
+#define OPB0_FSI_DATA_R 0x84
+
+#define OPB0_W_ENDIAN 0x4c
+#define OPB0_R_ENDIAN 0x5c
+
+/* OPB_IRQ_MASK */
+#define OPB1_XFER_ACK_EN BIT(17)
+#define OPB0_XFER_ACK_EN BIT(16)
+
+/* OPB_RW */
+#define CMD_READ BIT(0)
+#define CMD_WRITE 0
+
+/* OPBx_XFER_SIZE */
+#define XFER_FULLWORD (BIT(1) | BIT(0))
+#define XFER_HALFWORD (BIT(0))
+#define XFER_BYTE (0)
+
+#define FSI_LINK_ENABLE_SETUP_TIME 10 /* in mS */
+
+#define DEFAULT_DIVISOR 14
+#define OPB_POLL_TIMEOUT 10000
+
+static int __opb_write(struct fsi_master_aspeed *aspeed, u32 addr,
+ u32 val, u32 transfer_size)
+{
+ void __iomem *base = aspeed->base;
+ u32 reg, status;
+ int ret;
+
+ writel(CMD_WRITE, base + OPB0_RW);
+ writel(transfer_size, base + OPB0_XFER_SIZE);
+ writel(addr, base + OPB0_FSI_ADDR);
+ writel(val, base + OPB0_FSI_DATA_W);
+ writel(0x1, base + OPB_IRQ_CLEAR);
+ writel(0x1, base + OPB_TRIGGER);
+
+ ret = readl_poll_timeout(base + OPB_IRQ_STATUS, reg,
+ (reg & OPB0_XFER_ACK_EN) != 0,
+ 0, OPB_POLL_TIMEOUT);
+
+ status = readl(base + OPB0_STATUS);
+
+ /* Return error when poll timed out */
+ if (ret)
+ return ret;
+
+ /* Command failed, master will reset */
+ if (status & STATUS_ERR_ACK)
+ return -EIO;
+
+ return 0;
+}
+
+static int opb_writeb(struct fsi_master_aspeed *aspeed, u32 addr, u8 val)
+{
+ return __opb_write(aspeed, addr, val, XFER_BYTE);
+}
+
+static int opb_writew(struct fsi_master_aspeed *aspeed, u32 addr, __be16 val)
+{
+ return __opb_write(aspeed, addr, (__force u16)val, XFER_HALFWORD);
+}
+
+static int opb_writel(struct fsi_master_aspeed *aspeed, u32 addr, __be32 val)
+{
+ return __opb_write(aspeed, addr, (__force u32)val, XFER_FULLWORD);
+}
+
+static int __opb_read(struct fsi_master_aspeed *aspeed, uint32_t addr,
+ u32 transfer_size, void *out)
+{
+ void __iomem *base = aspeed->base;
+ u32 result, reg;
+ int status, ret;
+
+ writel(CMD_READ, base + OPB0_RW);
+ writel(transfer_size, base + OPB0_XFER_SIZE);
+ writel(addr, base + OPB0_FSI_ADDR);
+ writel(0x1, base + OPB_IRQ_CLEAR);
+ writel(0x1, base + OPB_TRIGGER);
+
+ ret = readl_poll_timeout(base + OPB_IRQ_STATUS, reg,
+ (reg & OPB0_XFER_ACK_EN) != 0,
+ 0, OPB_POLL_TIMEOUT);
+
+ status = readl(base + OPB0_STATUS);
+
+ result = readl(base + OPB0_FSI_DATA_R);
+
+ /* Return error when poll timed out */
+ if (ret)
+ return ret;
+
+ /* Command failed, master will reset */
+ if (status & STATUS_ERR_ACK)
+ return -EIO;
+
+ if (out) {
+ switch (transfer_size) {
+ case XFER_BYTE:
+ *(u8 *)out = result;
+ break;
+ case XFER_HALFWORD:
+ *(u16 *)out = result;
+ break;
+ case XFER_FULLWORD:
+ *(u32 *)out = result;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ }
+
+ return 0;
+}
+
+static int opb_readl(struct fsi_master_aspeed *aspeed, uint32_t addr, __be32 *out)
+{
+ return __opb_read(aspeed, addr, XFER_FULLWORD, out);
+}
+
+static int opb_readw(struct fsi_master_aspeed *aspeed, uint32_t addr, __be16 *out)
+{
+ return __opb_read(aspeed, addr, XFER_HALFWORD, (void *)out);
+}
+
+static int opb_readb(struct fsi_master_aspeed *aspeed, uint32_t addr, u8 *out)
+{
+ return __opb_read(aspeed, addr, XFER_BYTE, (void *)out);
+}
+
+static int check_errors(struct fsi_master_aspeed *aspeed, int err)
+{
+ int ret;
+
+ if (err == -EIO) {
+ /* Check MAEB (0x70) ? */
+
+ /* Then clear errors in master */
+ ret = opb_writel(aspeed, ctrl_base + FSI_MRESP0,
+ cpu_to_be32(FSI_MRESP_RST_ALL_MASTER));
+ if (ret) {
+ /* TODO: log? return different code? */
+ return ret;
+ }
+ /* TODO: confirm that 0x70 was okay */
+ }
+
+ /* This will pass through timeout errors */
+ return err;
+}
+
+static int aspeed_master_read(struct fsi_master *master, int link,
+ uint8_t id, uint32_t addr, void *val, size_t size)
+{
+ struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
+ int ret;
+
+ if (id != 0)
+ return -EINVAL;
+
+ addr += link * FSI_HUB_LINK_SIZE;
+
+ switch (size) {
+ case 1:
+ ret = opb_readb(aspeed, fsi_base + addr, val);
+ break;
+ case 2:
+ ret = opb_readw(aspeed, fsi_base + addr, val);
+ break;
+ case 4:
+ ret = opb_readl(aspeed, fsi_base + addr, val);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = check_errors(aspeed, ret);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int aspeed_master_write(struct fsi_master *master, int link,
+ uint8_t id, uint32_t addr, const void *val, size_t size)
+{
+ struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
+ int ret;
+
+ if (id != 0)
+ return -EINVAL;
+
+ addr += link * FSI_HUB_LINK_SIZE;
+
+ switch (size) {
+ case 1:
+ ret = opb_writeb(aspeed, fsi_base + addr, *(u8 *)val);
+ break;
+ case 2:
+ ret = opb_writew(aspeed, fsi_base + addr, *(__be16 *)val);
+ break;
+ case 4:
+ ret = opb_writel(aspeed, fsi_base + addr, *(__be32 *)val);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = check_errors(aspeed, ret);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int aspeed_master_link_enable(struct fsi_master *master, int link)
+{
+ struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
+ int idx, bit, ret;
+ __be32 reg, result;
+
+ idx = link / 32;
+ bit = link % 32;
+
+ reg = cpu_to_be32(0x80000000 >> bit);
+
+ ret = opb_writel(aspeed, ctrl_base + FSI_MSENP0 + (4 * idx), reg);
+ if (ret)
+ return ret;
+
+ mdelay(FSI_LINK_ENABLE_SETUP_TIME);
+
+ ret = opb_readl(aspeed, ctrl_base + FSI_MENP0 + (4 * idx), &result);
+ if (ret)
+ return ret;
+
+ if (result != reg) {
+ dev_err(aspeed->dev, "%s failed: %08x\n", __func__, result);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int aspeed_master_term(struct fsi_master *master, int link, uint8_t id)
+{
+ struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
+ uint32_t addr;
+ __be32 cmd;
+ int rc;
+
+ addr = 0x4;
+ cmd = cpu_to_be32(0xecc00000);
+
+ dev_dbg(aspeed->dev, "sending term to link %d slave %d\n", link, id);
+
+ rc = aspeed_master_write(master, link, id, addr, &cmd, 4);
+
+ dev_dbg(aspeed->dev, "term done (%d)\n", rc);
+
+ return rc;
+}
+
+static int aspeed_master_break(struct fsi_master *master, int link)
+{
+ struct fsi_master_aspeed *aspeed = to_fsi_master_aspeed(master);
+ uint32_t addr;
+ __be32 cmd;
+ int rc;
+
+ addr = 0x0;
+ cmd = cpu_to_be32(0xc0de0000);
+
+ dev_dbg(aspeed->dev, "sending break to link %d\n", link);
+
+ rc = aspeed_master_write(master, link, 0, addr, &cmd, 4);
+
+ dev_dbg(aspeed->dev, "break done (%d)\n", rc);
+
+ return rc;
+}
+
+static void aspeed_master_release(struct device *dev)
+{
+ struct fsi_master_aspeed *aspeed =
+ to_fsi_master_aspeed(dev_to_fsi_master(dev));
+
+ kfree(aspeed);
+}
+
+/* mmode encoders */
+static inline u32 fsi_mmode_crs0(u32 x)
+{
+ return (x & FSI_MMODE_CRS0MASK) << FSI_MMODE_CRS0SHFT;
+}
+
+static inline u32 fsi_mmode_crs1(u32 x)
+{
+ return (x & FSI_MMODE_CRS1MASK) << FSI_MMODE_CRS1SHFT;
+}
+
+static int aspeed_master_init(struct fsi_master_aspeed *aspeed)
+{
+ __be32 reg;
+
+ reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK
+ | FSI_MRESP_RST_MCR | FSI_MRESP_RST_PYE);
+ opb_writel(aspeed, ctrl_base + FSI_MRESP0, reg);
+
+ /* Initialize the MFSI (hub master) engine */
+ reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK
+ | FSI_MRESP_RST_MCR | FSI_MRESP_RST_PYE);
+ opb_writel(aspeed, ctrl_base + FSI_MRESP0, reg);
+
+ reg = cpu_to_be32(FSI_MECTRL_EOAE | FSI_MECTRL_P8_AUTO_TERM);
+ opb_writel(aspeed, ctrl_base + FSI_MECTRL, reg);
+
+ reg = cpu_to_be32(FSI_MMODE_ECRC | FSI_MMODE_EPC | FSI_MMODE_RELA
+ | fsi_mmode_crs0(DEFAULT_DIVISOR)
+ | fsi_mmode_crs1(DEFAULT_DIVISOR)
+ | FSI_MMODE_P8_TO_LSB);
+ opb_writel(aspeed, ctrl_base + FSI_MMODE, reg);
+
+ reg = cpu_to_be32(0xffff0000);
+ opb_writel(aspeed, ctrl_base + FSI_MDLYR, reg);
+
+ reg = cpu_to_be32(~0);
+ opb_writel(aspeed, ctrl_base + FSI_MSENP0, reg);
+
+ /* Leave enabled long enough for master logic to set up */
+ mdelay(FSI_LINK_ENABLE_SETUP_TIME);
+
+ opb_writel(aspeed, ctrl_base + FSI_MCENP0, reg);
+
+ opb_readl(aspeed, ctrl_base + FSI_MAEB, NULL);
+
+ reg = cpu_to_be32(FSI_MRESP_RST_ALL_MASTER | FSI_MRESP_RST_ALL_LINK);
+ opb_writel(aspeed, ctrl_base + FSI_MRESP0, reg);
+
+ opb_readl(aspeed, ctrl_base + FSI_MLEVP0, NULL);
+
+ /* Reset the master bridge */
+ reg = cpu_to_be32(FSI_MRESB_RST_GEN);
+ opb_writel(aspeed, ctrl_base + FSI_MRESB0, reg);
+
+ reg = cpu_to_be32(FSI_MRESB_RST_ERR);
+ opb_writel(aspeed, ctrl_base + FSI_MRESB0, reg);
+
+ return 0;
+}
+
+static int fsi_master_aspeed_probe(struct platform_device *pdev)
+{
+ struct fsi_master_aspeed *aspeed;
+ struct resource *res;
+ int rc, links, reg;
+ __be32 raw;
+
+ aspeed = devm_kzalloc(&pdev->dev, sizeof(*aspeed), GFP_KERNEL);
+ if (!aspeed)
+ return -ENOMEM;
+
+ aspeed->dev = &pdev->dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ aspeed->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(aspeed->base))
+ return PTR_ERR(aspeed->base);
+
+ aspeed->clk = devm_clk_get(aspeed->dev, NULL);
+ if (IS_ERR(aspeed->clk)) {
+ dev_err(aspeed->dev, "couldn't get clock\n");
+ return PTR_ERR(aspeed->clk);
+ }
+ rc = clk_prepare_enable(aspeed->clk);
+ if (rc) {
+ dev_err(aspeed->dev, "couldn't enable clock\n");
+ return rc;
+ }
+
+ writel(0x1, aspeed->base + OPB_CLK_SYNC);
+ writel(OPB1_XFER_ACK_EN | OPB0_XFER_ACK_EN,
+ aspeed->base + OPB_IRQ_MASK);
+ /* TODO: Try without this */
+ writel(0x10, aspeed->base + 0x64); // Retry counter number ???
+ writel(0x0f, aspeed->base + 0xe4); // DMA Enable
+
+ writel(ctrl_base, aspeed->base + OPB_CTRL_BASE);
+ writel(fsi_base, aspeed->base + OPB_FSI_BASE);
+
+ /* Set read data order */
+ writel(0x0011bb1b, aspeed->base + OPB0_R_ENDIAN);
+
+ /* Set write data order */
+ writel(0x0011bb1b, aspeed->base + OPB0_W_ENDIAN);
+ writel(0xffaa5500, aspeed->base + 0x50);
+
+ /*
+ * Select OPB0 for all operations.
+ * Will need to be reworked when enabling DMA or anything that uses
+ * OPB1.
+ */
+ writel(0x1, aspeed->base + OPB0_SELECT);
+
+ rc = opb_readl(aspeed, ctrl_base + FSI_MVER, &raw);
+ if (rc) {
+ dev_err(&pdev->dev, "failed to read hub version\n");
+ return rc;
+ }
+
+ reg = be32_to_cpu(raw);
+ links = (reg >> 8) & 0xff;
+ dev_info(&pdev->dev, "hub version %08x (%d links)\n", reg, links);
+
+ aspeed->master.dev.parent = &pdev->dev;
+ aspeed->master.dev.release = aspeed_master_release;
+ aspeed->master.dev.of_node = of_node_get(dev_of_node(&pdev->dev));
+
+ aspeed->master.n_links = links;
+ aspeed->master.read = aspeed_master_read;
+ aspeed->master.write = aspeed_master_write;
+ aspeed->master.send_break = aspeed_master_break;
+ aspeed->master.term = aspeed_master_term;
+ aspeed->master.link_enable = aspeed_master_link_enable;
+
+ dev_set_drvdata(&pdev->dev, aspeed);
+
+ aspeed_master_init(aspeed);
+
+ rc = fsi_master_register(&aspeed->master);
+ if (rc)
+ goto err_release;
+
+ /* At this point, fsi_master_register performs the device_initialize(),
+ * and holds the sole reference on master.dev. This means the device
+ * will be freed (via ->release) during any subsequent call to
+ * fsi_master_unregister. We add our own reference to it here, so we
+ * can perform cleanup (in _remove()) without it being freed before
+ * we're ready.
+ */
+ get_device(&aspeed->master.dev);
+ return 0;
+
+err_release:
+ clk_disable_unprepare(aspeed->clk);
+ return rc;
+}
+
+static int fsi_master_aspeed_remove(struct platform_device *pdev)
+{
+ struct fsi_master_aspeed *aspeed = platform_get_drvdata(pdev);
+
+ fsi_master_unregister(&aspeed->master);
+ clk_disable_unprepare(aspeed->clk);
+
+ return 0;
+}
+
+static const struct of_device_id fsi_master_aspeed_match[] = {
+ { .compatible = "aspeed,ast2600-fsi-master" },
+ { },
+};
+
+static struct platform_driver fsi_master_aspeed_driver = {
+ .driver = {
+ .name = "fsi-master-aspeed",
+ .of_match_table = fsi_master_aspeed_match,
+ },
+ .probe = fsi_master_aspeed_probe,
+ .remove = fsi_master_aspeed_remove,
+};
+
+module_platform_driver(fsi_master_aspeed_driver);
+MODULE_LICENSE("GPL");
--
2.24.0.rc1
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