  One of the most promising probes to constrain the reionization history of the
universe is the power spectrum of neutral hydrogen 21 cm emission fluctuations.
The corresponding analyses require computationally efficient modelling of
reionization, usually achieved through semi-numerical simulations. We
investigate the capability of one such semi-numerical code, SCRIPT, to
constrain the reionization parameters. Our study involves creating a mock data
set corresponding to the upcoming SKA-Low, followed by a Bayesian inference
method to constrain the model parameters. In particular, we explore in detail
whether the inferred parameters are unbiased with respect to the inputs used
for the mock, and also if the inferences are insensitive to the resolution of
the simulation. We find that the model is successful on both fronts. We also
develop a simple template model of reionization which can mimic the complex
physical processes like inhomogeneous recombinations and radiative feedback and
show that it can recover the global reionization history reliably with moderate
computational cost. However, such simple models are not suitable for
constraining the properties of the ionizing sources. Our results are relevant
for constraining reionization using high-quality data expected in future
telescopes.
