--- /dev/null
+// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
+/* Copyright (c) 2019 Mellanox Technologies */
+
+#include <linux/pci.h>
+#include "mlx5_core.h"
+#include "pci_vsc.h"
+
+#define MLX5_EXTRACT_C(source, offset, size) \
+ ((((u32)(source)) >> (offset)) & MLX5_ONES32(size))
+#define MLX5_EXTRACT(src, start, len) \
+ (((len) == 32) ? (src) : MLX5_EXTRACT_C(src, start, len))
+#define MLX5_ONES32(size) \
+ ((size) ? (0xffffffff >> (32 - (size))) : 0)
+#define MLX5_MASK32(offset, size) \
+ (MLX5_ONES32(size) << (offset))
+#define MLX5_MERGE_C(rsrc1, rsrc2, start, len) \
+ ((((rsrc2) << (start)) & (MLX5_MASK32((start), (len)))) | \
+ ((rsrc1) & (~MLX5_MASK32((start), (len)))))
+#define MLX5_MERGE(rsrc1, rsrc2, start, len) \
+ (((len) == 32) ? (rsrc2) : MLX5_MERGE_C(rsrc1, rsrc2, start, len))
+#define vsc_read(dev, offset, val) \
+ pci_read_config_dword((dev)->pdev, (dev)->vsc_addr + (offset), (val))
+#define vsc_write(dev, offset, val) \
+ pci_write_config_dword((dev)->pdev, (dev)->vsc_addr + (offset), (val))
+#define VSC_MAX_RETRIES 2048
+
+enum mlx5_vsc_state {
+ MLX5_VSC_UNLOCK,
+ MLX5_VSC_LOCK,
+};
+
+enum {
+ VSC_CTRL_OFFSET = 0x4,
+ VSC_COUNTER_OFFSET = 0x8,
+ VSC_SEMAPHORE_OFFSET = 0xc,
+ VSC_ADDR_OFFSET = 0x10,
+ VSC_DATA_OFFSET = 0x14,
+
+ VSC_FLAG_BIT_OFFS = 31,
+ VSC_FLAG_BIT_LEN = 1,
+
+ VSC_SYND_BIT_OFFS = 30,
+ VSC_SYND_BIT_LEN = 1,
+
+ VSC_ADDR_BIT_OFFS = 0,
+ VSC_ADDR_BIT_LEN = 30,
+
+ VSC_SPACE_BIT_OFFS = 0,
+ VSC_SPACE_BIT_LEN = 16,
+
+ VSC_SIZE_VLD_BIT_OFFS = 28,
+ VSC_SIZE_VLD_BIT_LEN = 1,
+
+ VSC_STATUS_BIT_OFFS = 29,
+ VSC_STATUS_BIT_LEN = 3,
+};
+
+void mlx5_pci_vsc_init(struct mlx5_core_dev *dev)
+{
+ if (!mlx5_core_is_pf(dev))
+ return;
+
+ dev->vsc_addr = pci_find_capability(dev->pdev,
+ PCI_CAP_ID_VNDR);
+ if (!dev->vsc_addr)
+ mlx5_core_warn(dev, "Failed to get valid vendor specific ID\n");
+}
+
+int mlx5_vsc_gw_lock(struct mlx5_core_dev *dev)
+{
+ u32 counter = 0;
+ int retries = 0;
+ u32 lock_val;
+ int ret;
+
+ pci_cfg_access_lock(dev->pdev);
+ do {
+ if (retries > VSC_MAX_RETRIES) {
+ ret = -EBUSY;
+ goto pci_unlock;
+ }
+
+ /* Check if semaphore is already locked */
+ ret = vsc_read(dev, VSC_SEMAPHORE_OFFSET, &lock_val);
+ if (ret)
+ goto pci_unlock;
+
+ if (lock_val) {
+ retries++;
+ usleep_range(1000, 2000);
+ continue;
+ }
+
+ /* Read and write counter value, if written value is
+ * the same, semaphore was acquired successfully.
+ */
+ ret = vsc_read(dev, VSC_COUNTER_OFFSET, &counter);
+ if (ret)
+ goto pci_unlock;
+
+ ret = vsc_write(dev, VSC_SEMAPHORE_OFFSET, counter);
+ if (ret)
+ goto pci_unlock;
+
+ ret = vsc_read(dev, VSC_SEMAPHORE_OFFSET, &lock_val);
+ if (ret)
+ goto pci_unlock;
+
+ retries++;
+ } while (counter != lock_val);
+
+ return 0;
+
+pci_unlock:
+ pci_cfg_access_unlock(dev->pdev);
+ return ret;
+}
+
+int mlx5_vsc_gw_unlock(struct mlx5_core_dev *dev)
+{
+ int ret;
+
+ ret = vsc_write(dev, VSC_SEMAPHORE_OFFSET, MLX5_VSC_UNLOCK);
+ pci_cfg_access_unlock(dev->pdev);
+ return ret;
+}
+
+int mlx5_vsc_gw_set_space(struct mlx5_core_dev *dev, u16 space,
+ u32 *ret_space_size)
+{
+ int ret;
+ u32 val = 0;
+
+ if (!mlx5_vsc_accessible(dev))
+ return -EINVAL;
+
+ if (ret_space_size)
+ *ret_space_size = 0;
+
+ /* Get a unique val */
+ ret = vsc_read(dev, VSC_CTRL_OFFSET, &val);
+ if (ret)
+ goto out;
+
+ /* Try to modify the lock */
+ val = MLX5_MERGE(val, space, VSC_SPACE_BIT_OFFS, VSC_SPACE_BIT_LEN);
+ ret = vsc_write(dev, VSC_CTRL_OFFSET, val);
+ if (ret)
+ goto out;
+
+ /* Verify lock was modified */
+ ret = vsc_read(dev, VSC_CTRL_OFFSET, &val);
+ if (ret)
+ goto out;
+
+ if (MLX5_EXTRACT(val, VSC_STATUS_BIT_OFFS, VSC_STATUS_BIT_LEN) == 0)
+ return -EINVAL;
+
+ /* Get space max address if indicated by size valid bit */
+ if (ret_space_size &&
+ MLX5_EXTRACT(val, VSC_SIZE_VLD_BIT_OFFS, VSC_SIZE_VLD_BIT_LEN)) {
+ ret = vsc_read(dev, VSC_ADDR_OFFSET, &val);
+ if (ret) {
+ mlx5_core_warn(dev, "Failed to get max space size\n");
+ goto out;
+ }
+ *ret_space_size = MLX5_EXTRACT(val, VSC_ADDR_BIT_OFFS,
+ VSC_ADDR_BIT_LEN);
+ }
+ return 0;
+
+out:
+ return ret;
+}
+
+static int mlx5_vsc_wait_on_flag(struct mlx5_core_dev *dev, u8 expected_val)
+{
+ int retries = 0;
+ u32 flag;
+ int ret;
+
+ do {
+ if (retries > VSC_MAX_RETRIES)
+ return -EBUSY;
+
+ ret = vsc_read(dev, VSC_ADDR_OFFSET, &flag);
+ if (ret)
+ return ret;
+ flag = MLX5_EXTRACT(flag, VSC_FLAG_BIT_OFFS, VSC_FLAG_BIT_LEN);
+ retries++;
+
+ if ((retries & 0xf) == 0)
+ usleep_range(1000, 2000);
+
+ } while (flag != expected_val);
+
+ return 0;
+}
+
+static int mlx5_vsc_gw_write(struct mlx5_core_dev *dev, unsigned int address,
+ u32 data)
+{
+ int ret;
+
+ if (MLX5_EXTRACT(address, VSC_SYND_BIT_OFFS,
+ VSC_FLAG_BIT_LEN + VSC_SYND_BIT_LEN))
+ return -EINVAL;
+
+ /* Set flag to 0x1 */
+ address = MLX5_MERGE(address, 1, VSC_FLAG_BIT_OFFS, 1);
+ ret = vsc_write(dev, VSC_DATA_OFFSET, data);
+ if (ret)
+ goto out;
+
+ ret = vsc_write(dev, VSC_ADDR_OFFSET, address);
+ if (ret)
+ goto out;
+
+ /* Wait for the flag to be cleared */
+ ret = mlx5_vsc_wait_on_flag(dev, 0);
+
+out:
+ return ret;
+}
+
+static int mlx5_vsc_gw_read(struct mlx5_core_dev *dev, unsigned int address,
+ u32 *data)
+{
+ int ret;
+
+ if (MLX5_EXTRACT(address, VSC_SYND_BIT_OFFS,
+ VSC_FLAG_BIT_LEN + VSC_SYND_BIT_LEN))
+ return -EINVAL;
+
+ ret = vsc_write(dev, VSC_ADDR_OFFSET, address);
+ if (ret)
+ goto out;
+
+ ret = mlx5_vsc_wait_on_flag(dev, 1);
+ if (ret)
+ goto out;
+
+ ret = vsc_read(dev, VSC_DATA_OFFSET, data);
+out:
+ return ret;
+}
+
+static int mlx5_vsc_gw_read_fast(struct mlx5_core_dev *dev,
+ unsigned int read_addr,
+ unsigned int *next_read_addr,
+ u32 *data)
+{
+ int ret;
+
+ ret = mlx5_vsc_gw_read(dev, read_addr, data);
+ if (ret)
+ goto out;
+
+ ret = vsc_read(dev, VSC_ADDR_OFFSET, next_read_addr);
+ if (ret)
+ goto out;
+
+ *next_read_addr = MLX5_EXTRACT(*next_read_addr, VSC_ADDR_BIT_OFFS,
+ VSC_ADDR_BIT_LEN);
+
+ if (*next_read_addr <= read_addr)
+ ret = -EINVAL;
+out:
+ return ret;
+}
+
+int mlx5_vsc_gw_read_block_fast(struct mlx5_core_dev *dev, u32 *data,
+ int length)
+{
+ unsigned int next_read_addr = 0;
+ unsigned int read_addr = 0;
+
+ while (read_addr < length) {
+ if (mlx5_vsc_gw_read_fast(dev, read_addr, &next_read_addr,
+ &data[(read_addr >> 2)]))
+ return read_addr;
+
+ read_addr = next_read_addr;
+ }
+ return length;
+}
projects / linux-2.6-block.git / commitdiff