irqchip/gic-v3-its: Workaround HiSilicon Hip07 redistributor addressing

The ITSes on the Hip07 (as present in the Huawei D05) are broken when
it comes to addressing the redistributors, and need to be explicitely
told to address the VLPI page instead of the redistributor base address.

So let's add yet another quirk, fixing up the target address
in the command stream.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Documentation/arm64/silicon-errata.txt

@@ -70,6 +70,7 @@ stable kernels.
 |                |                 |                 |                             |
 | Hisilicon      | Hip0{5,6,7}     | #161010101      | HISILICON_ERRATUM_161010101 |
 | Hisilicon      | Hip0{6,7}       | #161010701      | N/A                         |
+| Hisilicon      | Hip07           | #161600802      | HISILICON_ERRATUM_161600802 |
 |                |                 |                 |                             |
 | Qualcomm Tech. | Falkor v1       | E1003           | QCOM_FALKOR_ERRATUM_1003    |
 | Qualcomm Tech. | Falkor v1       | E1009           | QCOM_FALKOR_ERRATUM_1009    |

arch/arm64/Kconfig

@@ -539,6 +539,7 @@ config QCOM_QDF2400_ERRATUM_0065
 
 	  If unsure, say Y.
 
+
 config SOCIONEXT_SYNQUACER_PREITS
 	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
 	default y
@@ -546,6 +547,16 @@ config SOCIONEXT_SYNQUACER_PREITS
 	  Socionext Synquacer SoCs implement a separate h/w block to generate
 	  MSI doorbell writes with non-zero values for the device ID.
 
+	  If unsure, say Y.
+
+config HISILICON_ERRATUM_161600802
+	bool "Hip07 161600802: Erroneous redistributor VLPI base"
+	default y
+	help
+	  The HiSilicon Hip07 SoC usees the wrong redistributor base
+	  when issued ITS commands such as VMOVP and VMAPP, and requires
+	  a 128kB offset to be applied to the target address in this commands.
+
 	  If unsure, say Y.
 endmenu
 

drivers/irqchip/irq-gic-v3-its.c

@@ -109,6 +109,7 @@ struct its_node {
 	unsigned int		msi_domain_flags;
 	u32			pre_its_base; /* for Socionext Synquacer */
 	bool			is_v4;
+	int			vlpi_redist_offset;
 };
 
 #define ITS_ITT_ALIGN		SZ_256
@@ -558,13 +559,15 @@ static struct its_vpe *its_build_vmapp_cmd(struct its_node *its,
 					   struct its_cmd_desc *desc)
 {
 	unsigned long vpt_addr;
+	u64 target;
 
 	vpt_addr = virt_to_phys(page_address(desc->its_vmapp_cmd.vpe->vpt_page));
+	target = desc->its_vmapp_cmd.col->target_address + its->vlpi_redist_offset;
 
 	its_encode_cmd(cmd, GITS_CMD_VMAPP);
 	its_encode_vpeid(cmd, desc->its_vmapp_cmd.vpe->vpe_id);
 	its_encode_valid(cmd, desc->its_vmapp_cmd.valid);
-	its_encode_target(cmd, desc->its_vmapp_cmd.col->target_address);
+	its_encode_target(cmd, target);
 	its_encode_vpt_addr(cmd, vpt_addr);
 	its_encode_vpt_size(cmd, LPI_NRBITS - 1);
 
@@ -623,11 +626,14 @@ static struct its_vpe *its_build_vmovp_cmd(struct its_node *its,
 					   struct its_cmd_block *cmd,
 					   struct its_cmd_desc *desc)
 {
+	u64 target;
+
+	target = desc->its_vmovp_cmd.col->target_address + its->vlpi_redist_offset;
 	its_encode_cmd(cmd, GITS_CMD_VMOVP);
 	its_encode_seq_num(cmd, desc->its_vmovp_cmd.seq_num);
 	its_encode_its_list(cmd, desc->its_vmovp_cmd.its_list);
 	its_encode_vpeid(cmd, desc->its_vmovp_cmd.vpe->vpe_id);
-	its_encode_target(cmd, desc->its_vmovp_cmd.col->target_address);
+	its_encode_target(cmd, target);
 
 	its_fixup_cmd(cmd);
 
@@ -2834,6 +2840,18 @@ static bool __maybe_unused its_enable_quirk_socionext_synquacer(void *data)
 	return false;
 }
 
+static bool __maybe_unused its_enable_quirk_hip07_161600802(void *data)
+{
+	struct its_node *its = data;
+
+	/*
+	 * Hip07 insists on using the wrong address for the VLPI
+	 * page. Trick it into doing the right thing...
+	 */
+	its->vlpi_redist_offset = SZ_128K;
+	return true;
+}
+
 static const struct gic_quirk its_quirks[] = {
 #ifdef CONFIG_CAVIUM_ERRATUM_22375
 	{
@@ -2871,6 +2889,14 @@ static const struct gic_quirk its_quirks[] = {
 		.mask	= 0xffffffff,
 		.init	= its_enable_quirk_socionext_synquacer,
 	},
+#endif
+#ifdef CONFIG_HISILICON_ERRATUM_161600802
+	{
+		.desc	= "ITS: Hip07 erratum 161600802",
+		.iidr	= 0x00000004,
+		.mask	= 0xffffffff,
+		.init	= its_enable_quirk_hip07_161600802,
+	},
 #endif
 	{
 	}