From 7e4237dbe494f9721463fd1f2d3b9e52ec74930e Mon Sep 17 00:00:00 2001 From: Tom St Denis Date: Wed, 2 May 2018 13:01:36 -0400 Subject: [PATCH] drm/amd/amdgpu: Add some documentation to the debugfs entries Signed-off-by: Tom St Denis Reviewed-by: Huang Rui Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c | 193 +++++++++++++++++++- 1 file changed, 189 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c index c98e59721444..f5fb93795a69 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_debugfs.c @@ -28,8 +28,13 @@ #include #include "amdgpu.h" -/* - * Debugfs +/** + * amdgpu_debugfs_add_files - Add simple debugfs entries + * + * @adev: Device to attach debugfs entries to + * @files: Array of function callbacks that respond to reads + * @nfiles: Number of callbacks to register + * */ int amdgpu_debugfs_add_files(struct amdgpu_device *adev, const struct drm_info_list *files, @@ -64,7 +69,33 @@ int amdgpu_debugfs_add_files(struct amdgpu_device *adev, #if defined(CONFIG_DEBUG_FS) - +/** + * amdgpu_debugfs_process_reg_op - Handle MMIO register reads/writes + * + * @read: True if reading + * @f: open file handle + * @buf: User buffer to write/read to + * @size: Number of bytes to write/read + * @pos: Offset to seek to + * + * This debugfs entry has special meaning on the offset being sought. + * Various bits have different meanings: + * + * Bit 62: Indicates a GRBM bank switch is needed + * Bit 61: Indicates a SRBM bank switch is needed (implies bit 62 is + * zero) + * Bits 24..33: The SE or ME selector if needed + * Bits 34..43: The SH (or SA) or PIPE selector if needed + * Bits 44..53: The INSTANCE (or CU/WGP) or QUEUE selector if needed + * + * Bit 23: Indicates that the PM power gating lock should be held + * This is necessary to read registers that might be + * unreliable during a power gating transistion. + * + * The lower bits are the BYTE offset of the register to read. This + * allows reading multiple registers in a single call and having + * the returned size reflect that. + */ static int amdgpu_debugfs_process_reg_op(bool read, struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -164,19 +195,37 @@ static int amdgpu_debugfs_process_reg_op(bool read, struct file *f, return result; } - +/** + * amdgpu_debugfs_regs_read - Callback for reading MMIO registers + */ static ssize_t amdgpu_debugfs_regs_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { return amdgpu_debugfs_process_reg_op(true, f, buf, size, pos); } +/** + * amdgpu_debugfs_regs_write - Callback for writing MMIO registers + */ static ssize_t amdgpu_debugfs_regs_write(struct file *f, const char __user *buf, size_t size, loff_t *pos) { return amdgpu_debugfs_process_reg_op(false, f, (char __user *)buf, size, pos); } + +/** + * amdgpu_debugfs_regs_pcie_read - Read from a PCIE register + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * The lower bits are the BYTE offset of the register to read. This + * allows reading multiple registers in a single call and having + * the returned size reflect that. + */ static ssize_t amdgpu_debugfs_regs_pcie_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -204,6 +253,18 @@ static ssize_t amdgpu_debugfs_regs_pcie_read(struct file *f, char __user *buf, return result; } +/** + * amdgpu_debugfs_regs_pcie_write - Write to a PCIE register + * + * @f: open file handle + * @buf: User buffer to write data from + * @size: Number of bytes to write + * @pos: Offset to seek to + * + * The lower bits are the BYTE offset of the register to write. This + * allows writing multiple registers in a single call and having + * the returned size reflect that. + */ static ssize_t amdgpu_debugfs_regs_pcie_write(struct file *f, const char __user *buf, size_t size, loff_t *pos) { @@ -232,6 +293,18 @@ static ssize_t amdgpu_debugfs_regs_pcie_write(struct file *f, const char __user return result; } +/** + * amdgpu_debugfs_regs_didt_read - Read from a DIDT register + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * The lower bits are the BYTE offset of the register to read. This + * allows reading multiple registers in a single call and having + * the returned size reflect that. + */ static ssize_t amdgpu_debugfs_regs_didt_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -259,6 +332,18 @@ static ssize_t amdgpu_debugfs_regs_didt_read(struct file *f, char __user *buf, return result; } +/** + * amdgpu_debugfs_regs_didt_write - Write to a DIDT register + * + * @f: open file handle + * @buf: User buffer to write data from + * @size: Number of bytes to write + * @pos: Offset to seek to + * + * The lower bits are the BYTE offset of the register to write. This + * allows writing multiple registers in a single call and having + * the returned size reflect that. + */ static ssize_t amdgpu_debugfs_regs_didt_write(struct file *f, const char __user *buf, size_t size, loff_t *pos) { @@ -287,6 +372,18 @@ static ssize_t amdgpu_debugfs_regs_didt_write(struct file *f, const char __user return result; } +/** + * amdgpu_debugfs_regs_smc_read - Read from a SMC register + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * The lower bits are the BYTE offset of the register to read. This + * allows reading multiple registers in a single call and having + * the returned size reflect that. + */ static ssize_t amdgpu_debugfs_regs_smc_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -314,6 +411,18 @@ static ssize_t amdgpu_debugfs_regs_smc_read(struct file *f, char __user *buf, return result; } +/** + * amdgpu_debugfs_regs_smc_write - Write to a SMC register + * + * @f: open file handle + * @buf: User buffer to write data from + * @size: Number of bytes to write + * @pos: Offset to seek to + * + * The lower bits are the BYTE offset of the register to write. This + * allows writing multiple registers in a single call and having + * the returned size reflect that. + */ static ssize_t amdgpu_debugfs_regs_smc_write(struct file *f, const char __user *buf, size_t size, loff_t *pos) { @@ -342,6 +451,20 @@ static ssize_t amdgpu_debugfs_regs_smc_write(struct file *f, const char __user * return result; } +/** + * amdgpu_debugfs_gca_config_read - Read from gfx config data + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * This file is used to access configuration data in a somewhat + * stable fashion. The format is a series of DWORDs with the first + * indicating which revision it is. New content is appended to the + * end so that older software can still read the data. + */ + static ssize_t amdgpu_debugfs_gca_config_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -418,6 +541,19 @@ static ssize_t amdgpu_debugfs_gca_config_read(struct file *f, char __user *buf, return result; } +/** + * amdgpu_debugfs_sensor_read - Read from the powerplay sensors + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * The offset is treated as the BYTE address of one of the sensors + * enumerated in amd/include/kgd_pp_interface.h under the + * 'amd_pp_sensors' enumeration. For instance to read the UVD VCLK + * you would use the offset 3 * 4 = 12. + */ static ssize_t amdgpu_debugfs_sensor_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -457,6 +593,27 @@ static ssize_t amdgpu_debugfs_sensor_read(struct file *f, char __user *buf, return !r ? outsize : r; } +/** amdgpu_debugfs_wave_read - Read WAVE STATUS data + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * The offset being sought changes which wave that the status data + * will be returned for. The bits are used as follows: + * + * Bits 0..6: Byte offset into data + * Bits 7..14: SE selector + * Bits 15..22: SH/SA selector + * Bits 23..30: CU/{WGP+SIMD} selector + * Bits 31..36: WAVE ID selector + * Bits 37..44: SIMD ID selector + * + * The returned data begins with one DWORD of version information + * Followed by WAVE STATUS registers relevant to the GFX IP version + * being used. See gfx_v8_0_read_wave_data() for an example output. + */ static ssize_t amdgpu_debugfs_wave_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -507,6 +664,28 @@ static ssize_t amdgpu_debugfs_wave_read(struct file *f, char __user *buf, return result; } +/** amdgpu_debugfs_gpr_read - Read wave gprs + * + * @f: open file handle + * @buf: User buffer to store read data in + * @size: Number of bytes to read + * @pos: Offset to seek to + * + * The offset being sought changes which wave that the status data + * will be returned for. The bits are used as follows: + * + * Bits 0..11: Byte offset into data + * Bits 12..19: SE selector + * Bits 20..27: SH/SA selector + * Bits 28..35: CU/{WGP+SIMD} selector + * Bits 36..43: WAVE ID selector + * Bits 37..44: SIMD ID selector + * Bits 52..59: Thread selector + * Bits 60..61: Bank selector (VGPR=0,SGPR=1) + * + * The return data comes from the SGPR or VGPR register bank for + * the selected operational unit. + */ static ssize_t amdgpu_debugfs_gpr_read(struct file *f, char __user *buf, size_t size, loff_t *pos) { @@ -637,6 +816,12 @@ static const char *debugfs_regs_names[] = { "amdgpu_gpr", }; +/** + * amdgpu_debugfs_regs_init - Initialize debugfs entries that provide + * register access. + * + * @adev: The device to attach the debugfs entries to + */ int amdgpu_debugfs_regs_init(struct amdgpu_device *adev) { struct drm_minor *minor = adev->ddev->primary;