arch/mips/cavium-octeon/executive/cvmx-helper-loop.c
Source file repositories/reference/linux-study-clean/arch/mips/cavium-octeon/executive/cvmx-helper-loop.c
File Facts
- System
- Linux kernel
- Corpus path
arch/mips/cavium-octeon/executive/cvmx-helper-loop.c- Extension
.c- Size
- 2712 bytes
- Lines
- 86
- Domain
- Architecture Layer
- Bucket
- arch/mips
- Inferred role
- Architecture Layer: implementation source
- Status
- source implementation candidate
Why This File Exists
CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
Dependency Surface
asm/octeon/octeon.hasm/octeon/cvmx-config.hasm/octeon/cvmx-helper.hasm/octeon/cvmx-pip-defs.h
Detected Declarations
function __cvmx_helper_loop_probefunction __cvmx_helper_loop_enable
Annotated Snippet
#include <asm/octeon/octeon.h>
#include <asm/octeon/cvmx-config.h>
#include <asm/octeon/cvmx-helper.h>
#include <asm/octeon/cvmx-pip-defs.h>
/**
* Probe a LOOP interface and determine the number of ports
* connected to it. The LOOP interface should still be down
* after this call.
*
* @interface: Interface to probe
*
* Returns Number of ports on the interface. Zero to disable.
*/
int __cvmx_helper_loop_probe(int interface)
{
union cvmx_ipd_sub_port_fcs ipd_sub_port_fcs;
int num_ports = 4;
int port;
/* We need to disable length checking so packet < 64 bytes and jumbo
frames don't get errors */
for (port = 0; port < num_ports; port++) {
union cvmx_pip_prt_cfgx port_cfg;
int ipd_port = cvmx_helper_get_ipd_port(interface, port);
port_cfg.u64 = cvmx_read_csr(CVMX_PIP_PRT_CFGX(ipd_port));
port_cfg.s.maxerr_en = 0;
port_cfg.s.minerr_en = 0;
cvmx_write_csr(CVMX_PIP_PRT_CFGX(ipd_port), port_cfg.u64);
}
/* Disable FCS stripping for loopback ports */
ipd_sub_port_fcs.u64 = cvmx_read_csr(CVMX_IPD_SUB_PORT_FCS);
ipd_sub_port_fcs.s.port_bit2 = 0;
cvmx_write_csr(CVMX_IPD_SUB_PORT_FCS, ipd_sub_port_fcs.u64);
return num_ports;
}
/**
* Bringup and enable a LOOP interface. After this call packet
* I/O should be fully functional. This is called with IPD
* enabled but PKO disabled.
*
* @interface: Interface to bring up
*
* Returns Zero on success, negative on failure
*/
int __cvmx_helper_loop_enable(int interface)
{
/* Do nothing. */
return 0;
}
Annotation
- Immediate include surface: `asm/octeon/octeon.h`, `asm/octeon/cvmx-config.h`, `asm/octeon/cvmx-helper.h`, `asm/octeon/cvmx-pip-defs.h`.
- Detected declarations: `function __cvmx_helper_loop_probe`, `function __cvmx_helper_loop_enable`.
- Atlas domain: Architecture Layer / arch/mips.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.