[PATCH 4/8] mailbox: tegra-hsp: Refactor in preparation of mailboxes

[cyndis@kapsi.fi (Mikko Perttunen)]

On 22.05.2018 18:36, Jon Hunter wrote:
> 
> On 08/05/18 12:43, Mikko Perttunen wrote:
>> The HSP driver is currently in many places written with the assumption
>> of only supporting doorbells. Prepare for the addition of shared
>> mailbox support by removing these assumptions and cleaning up the code.
>>
>> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
>> ---
>> ? drivers/mailbox/tegra-hsp.c | 124 
>> +++++++++++++++++++++++++++++---------------
>> ? 1 file changed, 82 insertions(+), 42 deletions(-)
>>
>> diff --git a/drivers/mailbox/tegra-hsp.c b/drivers/mailbox/tegra-hsp.c
>> index 0cde356c11ab..16eb970f2c9f 100644
>> --- a/drivers/mailbox/tegra-hsp.c
>> +++ b/drivers/mailbox/tegra-hsp.c
>> @@ -1,5 +1,5 @@
>> ? /*
>> - * Copyright (c) 2016, NVIDIA CORPORATION.? All rights reserved.
>> + * Copyright (c) 2016-2018, NVIDIA CORPORATION.? All rights reserved.
>> ?? *
>> ?? * This program is free software; you can redistribute it and/or 
>> modify it
>> ?? * under the terms and conditions of the GNU General Public License,
>> @@ -42,6 +42,7 @@ struct tegra_hsp_channel;
>> ? struct tegra_hsp;
>> ? struct tegra_hsp_channel {
>> +??? unsigned int type;
>> ????? struct tegra_hsp *hsp;
>> ????? struct mbox_chan *chan;
>> ????? void __iomem *regs;
>> @@ -55,6 +56,12 @@ struct tegra_hsp_doorbell {
>> ????? unsigned int index;
>> ? };
>> +static inline struct tegra_hsp_doorbell *
>> +channel_to_doorbell(struct tegra_hsp_channel *channel)
>> +{
>> +??? return container_of(channel, struct tegra_hsp_doorbell, channel);
>> +}
>> +
>> ? struct tegra_hsp_db_map {
>> ????? const char *name;
>> ????? unsigned int master;
>> @@ -69,7 +76,7 @@ struct tegra_hsp {
>> ????? const struct tegra_hsp_soc *soc;
>> ????? struct mbox_controller mbox;
>> ????? void __iomem *regs;
>> -??? unsigned int irq;
>> +??? unsigned int doorbell_irq;
>> ????? unsigned int num_sm;
>> ????? unsigned int num_as;
>> ????? unsigned int num_ss;
>> @@ -194,7 +201,7 @@ tegra_hsp_doorbell_create(struct tegra_hsp *hsp, 
>> const char *name,
>> ????? if (!db)
>> ????????? return ERR_PTR(-ENOMEM);
>> -??? offset = (1 + (hsp->num_sm / 2) + hsp->num_ss + hsp->num_as) << 16;
>> +??? offset = (1 + (hsp->num_sm / 2) + hsp->num_ss + hsp->num_as) * 
>> SZ_64K;
>> ????? offset += index * 0x100;
>> ????? db->channel.regs = hsp->regs + offset;
>> @@ -218,18 +225,8 @@ static void __tegra_hsp_doorbell_destroy(struct 
>> tegra_hsp_doorbell *db)
>> ????? kfree(db);
>> ? }
>> -static int tegra_hsp_doorbell_send_data(struct mbox_chan *chan, void 
>> *data)
>> -{
>> -??? struct tegra_hsp_doorbell *db = chan->con_priv;
>> -
>> -??? tegra_hsp_channel_writel(&db->channel, 1, HSP_DB_TRIGGER);
>> -
>> -??? return 0;
>> -}
>> -
>> -static int tegra_hsp_doorbell_startup(struct mbox_chan *chan)
>> +static int tegra_hsp_doorbell_startup(struct tegra_hsp_doorbell *db)
>> ? {
>> -??? struct tegra_hsp_doorbell *db = chan->con_priv;
>> ????? struct tegra_hsp *hsp = db->channel.hsp;
>> ????? struct tegra_hsp_doorbell *ccplex;
>> ????? unsigned long flags;
>> @@ -260,9 +257,8 @@ static int tegra_hsp_doorbell_startup(struct 
>> mbox_chan *chan)
>> ????? return 0;
>> ? }
>> -static void tegra_hsp_doorbell_shutdown(struct mbox_chan *chan)
>> +static void tegra_hsp_doorbell_shutdown(struct tegra_hsp_doorbell *db)
>> ? {
>> -??? struct tegra_hsp_doorbell *db = chan->con_priv;
>> ????? struct tegra_hsp *hsp = db->channel.hsp;
>> ????? struct tegra_hsp_doorbell *ccplex;
>> ????? unsigned long flags;
>> @@ -281,35 +277,61 @@ static void tegra_hsp_doorbell_shutdown(struct 
>> mbox_chan *chan)
>> ????? spin_unlock_irqrestore(&hsp->lock, flags);
>> ? }
>> -static const struct mbox_chan_ops tegra_hsp_doorbell_ops = {
>> -??? .send_data = tegra_hsp_doorbell_send_data,
>> -??? .startup = tegra_hsp_doorbell_startup,
>> -??? .shutdown = tegra_hsp_doorbell_shutdown,
>> +static int tegra_hsp_send_data(struct mbox_chan *chan, void *data)
>> +{
>> +??? struct tegra_hsp_channel *channel = chan->con_priv;
>> +??? struct tegra_hsp_doorbell *db;
>> +
>> +??? switch (channel->type) {
>> +??? case TEGRA_HSP_MBOX_TYPE_DB:
>> +??????? db = channel_to_doorbell(channel);
>> +??????? tegra_hsp_channel_writel(&db->channel, 1, HSP_DB_TRIGGER);
> 
> The above appears to be redundant. We go from channel to db and then end 
> up passing channels. Do we really need the 'db' struct above?

Fixed.

> 
>> +??? }
>> +
>> +??? return -EINVAL;
> 
> Does this function always return -EINVAL?

Fixed.

> 
>> +}
>> +
>> +static int tegra_hsp_startup(struct mbox_chan *chan)
>> +{
>> +??? struct tegra_hsp_channel *channel = chan->con_priv;
>> +
>> +??? switch (channel->type) {
>> +??? case TEGRA_HSP_MBOX_TYPE_DB:
>> +??????? return tegra_hsp_doorbell_startup(channel_to_doorbell(channel));
>> +??? }
>> +
>> +??? return -EINVAL;
>> +}
>> +
>> +static void tegra_hsp_shutdown(struct mbox_chan *chan)
>> +{
>> +??? struct tegra_hsp_channel *channel = chan->con_priv;
>> +
>> +??? switch (channel->type) {
>> +??? case TEGRA_HSP_MBOX_TYPE_DB:
>> +??????? tegra_hsp_doorbell_shutdown(channel_to_doorbell(channel));
>> +??????? break;
>> +??? }
>> +}
>> +
>> +static const struct mbox_chan_ops tegra_hsp_ops = {
>> +??? .send_data = tegra_hsp_send_data,
>> +??? .startup = tegra_hsp_startup,
>> +??? .shutdown = tegra_hsp_shutdown,
>> ? };
>> -static struct mbox_chan *of_tegra_hsp_xlate(struct mbox_controller 
>> *mbox,
>> -??????????????????????? const struct of_phandle_args *args)
>> +static struct mbox_chan *tegra_hsp_doorbell_xlate(struct tegra_hsp *hsp,
>> +????????????????????????? unsigned int master)
>> ? {
>> ????? struct tegra_hsp_channel *channel = ERR_PTR(-ENODEV);
>> -??? struct tegra_hsp *hsp = to_tegra_hsp(mbox);
>> -??? unsigned int type = args->args[0];
>> -??? unsigned int master = args->args[1];
>> ????? struct tegra_hsp_doorbell *db;
>> ????? struct mbox_chan *chan;
>> ????? unsigned long flags;
>> ????? unsigned int i;
>> -??? switch (type) {
>> -??? case TEGRA_HSP_MBOX_TYPE_DB:
>> -??????? db = tegra_hsp_doorbell_get(hsp, master);
>> -??????? if (db)
>> -??????????? channel = &db->channel;
>> -
>> -??????? break;
>> -
>> -??? default:
>> -??????? break;
>> -??? }
>> +??? db = tegra_hsp_doorbell_get(hsp, master);
>> +??? if (db)
>> +??????? channel = &db->channel;
>> ????? if (IS_ERR(channel))
>> ????????? return ERR_CAST(channel);
>> @@ -321,6 +343,7 @@ static struct mbox_chan *of_tegra_hsp_xlate(struct 
>> mbox_controller *mbox,
>> ????????? if (!chan->con_priv) {
>> ????????????? chan->con_priv = channel;
>> ????????????? channel->chan = chan;
>> +??????????? channel->type = TEGRA_HSP_MBOX_TYPE_DB;
>> ????????????? break;
> 
> I see that you are making the above only used for doorbells, but don't 
> we still need to set the chan->con_priv for shared mailboxes as well?

That's done elsewhere in the next patch that actually adds the shared 
mailbox support.

> 
> Cheers
> Jon
> 

Thanks,
Mikko