。
Morning wood and pissing — that's the extent of my remaining life force.
Literal
Morning-erection [and-や] urination [until-まで] [possessive-の] life [emphasis-かな].
朝立ち ('morning erection') is direct physiological vocabulary. しょんべん ('pissing') is vulgar for urination. までの命かな ('life only up to that point, I wonder') uses まで to cap the scope and かな for reflective musing. This is actually a senryū (comic haiku) — the 5-7-5 syllable structure is intentional: あさだちや (5) / しょんべんまでの (7) / いのちかな (5). The dark humor of reducing life to its basest biological functions is the point.