From: Mikko Perttunen Date: Tue, 12 Jan 2021 11:37:07 +0000 (+0200) Subject: drm/tegra: vic: Add comments on STREAMID registers X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=59e520a695e7c775d787d7108becc2662bde8061;p=linux.git drm/tegra: vic: Add comments on STREAMID registers Add comments clarifying use of the THI_STREAMID0 and THI_STREAMID1 registers. Signed-off-by: Mikko Perttunen Signed-off-by: Thierry Reding --- diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c index a3dbb8813fafe..48e98a60ab6ef 100644 --- a/drivers/gpu/drm/tegra/vic.c +++ b/drivers/gpu/drm/tegra/vic.c @@ -117,7 +117,19 @@ static int vic_boot(struct vic *vic) if (spec->num_ids > 0) { value = spec->ids[0] & 0xffff; + /* + * STREAMID0 is used for input/output buffers. + * Initialize it to SID_VIC in case context isolation + * is not enabled, and SID_VIC is used for both firmware + * and data buffers. + * + * If context isolation is enabled, it will be + * overridden by the SETSTREAMID opcode as part of + * each job. + */ vic_writel(vic, value, VIC_THI_STREAMID0); + + /* STREAMID1 is used for firmware loading. */ vic_writel(vic, value, VIC_THI_STREAMID1); } }